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SLS / Orion / Beyond-LEO HSF - Constellation => Heavy Lift Launch Vehicle (HLV/SLS) => Topic started by: Chris Bergin on 06/09/2017 08:47 pm

Title: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Chris Bergin on 06/09/2017 08:47 pm
Finally content where I can use some of Nathan's amazing L2 renders on the DSG! ;D

ASAP being positive about something!
https://www.nasaspaceflight.com/2017/06/asap-nasas-dsg-stepping-stone-mars/
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 06/09/2017 09:54 pm
Great article, and yes great images to support the story.

While the support of a well-watched advisory board is good, it does not change the political calculation for getting the overall DSG/DST plan approved and funded.

One thing I liked was:

"...NASA expected to publish individual documents for each system, such as environmental control and life support, power, data, storage, etc., that would contain voluntary standards rather than requirements, with the hope that both international and industry partners would be able to develop hardware and software that could easily be incorporated into the overall architecture, per the overview to the ASAP."

In this day and age of distributed contributions (think Github, open source s/w, etc.) I think providing a framework for identifying the known issues and being a "repository" for solutions makes a lot of sense. It leverages not only the "wisdom of the crowds", but also the resources of the planet. To me that was the most noteworthy part of the article.

As to the Deep Space Gateway, it's difficult to build things when you don't have very specific use cases for them. And I'm not talking about theoretical use cases, but real use cases that "customers" are vocal about needing to be solved. For instance, from the article:

“In terms of basic functionality, the DSG is being planned to support multiple NASA, commercial, and international objectives,” added the overview. “It would be designed for the deep space environment and would support a crew of 4 for total mission durations of up to 42 days with the Orion vehicle attached.

As of today there are really only two likely spacecraft that could use the DSG, the Orion MPCV and the Dragon Crew - I'm ignoring Soyuz for now.

We know that even though SpaceX is being paid to send two humans around the Moon, otherwise they are focused on building interplanetary spacecraft that can start to colonize Mars. So I don't see SpaceX themselves being interested in the DSG. Maybe a SpaceX customer would want to go, but I think there is a limited market for that.

Which leaves the Orion MPCV as the primary spacecraft that can reach the DSG. But because of the cost of the Orion and the SLS, and the production lead times for both with current factory capabilities, we're talking about 42 days in space per year at the DSG. Compared to the 6-12 months current U.S. astronauts spend on the ISS, I'm not sure what the value proposition is for spending 42 days in space. Sure the location is unique, but what is being learned in 12% of a year at the DSG vs 100% of the year at the ISS?

I mention that because there will need to be sponsors of the legislation for the DSG/DST in both the House and Senate, and they will need to be able to explain the value proposition to their fellow legislators and get them to set aside their priorities in order to fund this effort.

In internet startup terminology, I'm not seeing a "killer app" with the DSG, just a "nice to have". Things that are "nice to have" don't get funding priority, so I think NASA needs to work harder on identifying and explaining what the value proposition is for the Deep Space Gateway.

My $0.02
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: yg1968 on 06/09/2017 10:23 pm
I thought this quote in the article was also interesting:

Quote from: ASAP
“It would include a power and propulsion bus and a habitat, and would incorporate a logistics strategy that could involve cargo resupply or crew transportation flights by industry or international partners, such as what is done now for the ISS.”

Given that only one SLS is planned per year, Orion would also only be launched once a year. If NASA were to decide that it wants 2 or 3 crewed flights to the DSG per year, it could contract SpaceX or another commercial company for the other flights. That would be an interesting scenario.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/09/2017 10:29 pm
The 'killer app' for the DSG is sending people to Mars on the Deep Space Transport. To save fuel etc. the big ships will return to the DSG rather than LEO. An Orion could pick up the astronauts and return them to the Earth's surface.

IMHO The DSG day job will be sending people and cargo to the lunar surface. Reusable lunar landers will need to be parked and refuelled somewhere between missions.

Reusable LEO to DSG and back transfer vehicles will be useful. SEP for cargo and chemical rocket engines for people. Providing the LEO spacestation, DSG and transfer vehicle have NASA Docking Ports then NASA can simply buy tickets for the 3-4 day journey rather than pay for the vehicle's development.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 06/09/2017 11:26 pm
The 'killer app' for the DSG is sending people to Mars on the Deep Space Transport.

OK. Although at the funding level NASA has today industry experts don't think NASA will ever get to Mars, so at best this is a use case that is far in the future. Something more near-term is needed...

Quote
IMHO The DSG day job will be sending people and cargo to the lunar surface. Reusable lunar landers will need to be parked and refuelled somewhere between missions.

OK. So the near-term "killer app" for the Deep Space Gateway is a U.S. Government program to return humans to the surface of the Moon? Why hasn't this been made an explicit goal then?

Quote
Reusable LEO to DSG and back transfer vehicles will be useful. SEP for cargo and chemical rocket engines for people. Providing the LEO spacestation, DSG and transfer vehicle have NASA Docking Ports then NASA can simply buy tickets for the 3-4 day journey rather than pay for the vehicle's development.

All great stuff, but we shouldn't conflate personal desire with U.S. Government needs - because the USG doesn't have a current "need" to do any of that (as defined by USG policy and funding).

One way to look at the situation with the DSG/DST is whether this proposal would have been made regardless if the SLS & Orion existed or not? In other words, is the goal what's important, of the use of the SLS & Orion? And would the U.S. Government be willing to give up the SLS and Orion in order to pursue the DSG/DST effort if needed?

Those are questions the President needs to answer since it should be the President that proposes and supports such efforts. Obama had other priorities that he supported, some that succeeded and some that didn't, so we'll have to see if Trump is willing to attach his name to a long term effort too.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: okan170 on 06/10/2017 12:13 am
All great stuff, but we shouldn't conflate personal desire with U.S. Government needs - because the USG doesn't have a current "need" to do any of that (as defined by USG policy and funding).

One way to look at the situation with the DSG/DST is whether this proposal would have been made regardless if the SLS & Orion existed or not? In other words, is the goal what's important, of the use of the SLS & Orion? And would the U.S. Government be willing to give up the SLS and Orion in order to pursue the DSG/DST effort if needed?

As always, we come back to your assertion that we... shouldn't do anything at all until we 100% have congress and the president agreeing with full budget in-hand (which is never.)   ::)

We have a golden opportunity to do something that commercial and international partners are both interested in contributing to and using.  Its not an ideal plan, but its pretty good for what we have to work with and what money there is.  We can spend years arguing about what should be done or we can make a start on providing our own do-able cislunar toehold.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/10/2017 12:31 am
The 'killer app' for the DSG is sending people to Mars on the Deep Space Transport.

OK. Although at the funding level NASA has today industry experts don't think NASA will ever get to Mars, so at best this is a use case that is far in the future. Something more near-term is needed...

Quote
IMHO The DSG day job will be sending people and cargo to the lunar surface. Reusable lunar landers will need to be parked and refuelled somewhere between missions.

OK. So the near-term "killer app" for the Deep Space Gateway is a U.S. Government program to return humans to the surface of the Moon? Why hasn't this been made an explicit goal then?
{snip}

Obama did not ask for it, DSG is being managed by the Mars team and NASA would have to pay for an explicit goal. Providing support but no money to Lunar CATALYST industry/NASA partnership hopefully will produce several cargo lunar landers one of which is big enough to carry people. (The cabin will have to be a later project.) NASA is already looking for lunar surface payloads.
https://www.nasa.gov/feature/nasa-seeks-additional-information-on-small-lunar-surface-payloads (https://www.nasa.gov/feature/nasa-seeks-additional-information-on-small-lunar-surface-payloads)
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: northenarc on 06/10/2017 02:16 am
 I don't generally like to rain on space parades, and mods can pull this if they think it doesn't belong. I just feel this entire direction is a waste of time and money, it isn't going to get us to Mars, at least not anytime soon, and wouldn't even do that much to facilitate a moon base or missions that can't be done in other ways. I have trouble seeing the advantages, all this does is add another layer of unnecessary complexity. It sounds like something created to eat budgets. Sorry to be cynical.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/10/2017 02:52 am
I don't generally like to rain on space parades, and mods can pull this if they think it doesn't belong. I just feel this entire direction is a waste of time and money, it isn't going to get us to Mars, at least not anytime soon, and wouldn't even do that much to facilitate a moon base or missions that can't be done in other ways. I have trouble seeing the advantages, all this does is add another layer of unnecessary complexity. It sounds like something created to eat budgets. Sorry to be cynical.

NASA has a long term problem. It takes about a decade to develop a major machine. Unlike the Apollo days it can only afford to develop one major machine at a time. Going to Mars will require several new machines. It has chosen to work on an important component - long term life support. ECLSS are needed in capsules, transfer vehicles, spacestations, landers, spacesuits, planetary buildings and manned rovers. It has decided to flight test the ECLSS in a spacestation's habitat.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: yg1968 on 06/10/2017 03:10 am
I don't generally like to rain on space parades, and mods can pull this if they think it doesn't belong. I just feel this entire direction is a waste of time and money, it isn't going to get us to Mars, at least not anytime soon, and wouldn't even do that much to facilitate a moon base or missions that can't be done in other ways. I have trouble seeing the advantages, all this does is add another layer of unnecessary complexity. It sounds like something created to eat budgets. Sorry to be cynical.

I disagree. Regardless of where we go, we need habitats. I don't think that we are going to Mars any time soon. So this is what we get in the mean time. But this has to be done cheaply. If it's expensive, I agree that it then becomes a distraction.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: northenarc on 06/10/2017 03:13 am
I don't generally like to rain on space parades, and mods can pull this if they think it doesn't belong. I just feel this entire direction is a waste of time and money, it isn't going to get us to Mars, at least not anytime soon, and wouldn't even do that much to facilitate a moon base or missions that can't be done in other ways. I have trouble seeing the advantages, all this does is add another layer of unnecessary complexity. It sounds like something created to eat budgets. Sorry to be cynical.

NASA has a long term problem. It takes about a decade to develop a major machine. Unlike the Apollo days it can only afford to develop one major machine at a time. Going to Mars will require several new machines. It has chosen to work on an important component - long term life support. ECLSS are needed in capsules, transfer vehicles, spacestations, landers, spacesuits, planetary buildings and manned rovers. It has decided to flight test the ECLSS in a spacestation's habitat.
  I do not deny your points, NASA is doing the best they feel they can with the current circumstances, doing something different with the same money might well require unpopular things. We can blame the last decade of conflicted and uncertain direction from all quarters for the current state of affairs. I think a small lunar base would better serve all of our long term exploration goals for getting to Mars, a cislunar stations' only advantage is not needing to be landed or landed at, we could always send out smaller modules for fueling if we decided to go that direction. And we really don't want to hire the military industrial complex as the only gas station for interplanetary missions, and it sounds like they'd love to have that monopoly.     
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: RonM on 06/10/2017 03:39 am
Each Orion launch on SLS Block 1B will have about 10 tonnes payload capacity unused. NASA is trying to do something with that excess capacity. So, DSG is actually a pretty good idea considering the situation.

If DSG turns out to be just a tin can for astronauts to sit in, it won't be very useful. If our ISS partners join up with NASA and add lunar landers, especially reusable ones to be docked at DSG, then it will be money well spent.

SLS and Orion are Congressional pet projects. They will continue to be funded for the foreseeable future. Might as well get some good use out of them.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/10/2017 03:56 am
  I do not deny your points, NASA is doing the best they feel they can with the current circumstances, doing something different with the same money might well require unpopular things. We can blame the last decade of conflicted and uncertain direction from all quarters for the current state of affairs. I think a small lunar base would better serve all of our long term exploration goals for getting to Mars, a cislunar stations' only advantage is not needing to be landed or landed at, we could always send out smaller modules for fueling if we decided to go that direction. And we really don't want to hire the military industrial complex as the only gas station for interplanetary missions, and it sounds like they'd love to have that monopoly.     

Since they are self catering I sometimes think of these spacestations as YMCA in space.

Out of the way hotels probably have experience with logistics. Bigelow both builds and runs hotels. The oil companies run gas stations and are used to drilling off road. Walmart may be able to submit a very different bid.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: okan170 on 06/10/2017 03:59 am
I think a small lunar base would better serve all of our long term exploration goals for getting to Mars, a cislunar stations' only advantage is not needing to be landed or landed at, we could always send out smaller modules for fueling if we decided to go that direction. And we really don't want to hire the military industrial complex as the only gas station for interplanetary missions, and it sounds like they'd love to have that monopoly.     

One big advantage of the station is that, according to Gerst, it can be done within the relatively flat NASA budgets.  A surface base would be nice, but it requires commitment and funding that is not there and may not materialize for some time.  This is what we can do now with what we have and even Bezos has expressed interest in basing a lander there.

We also don't want to have the only gas station held by corporate space interests instead of the military industrial complex if thats what you're implying.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/10/2017 04:15 am
{snip}

We also don't want to have the only gas station held by corporate space interests instead of the military industrial complex if thats what you're implying.

If there is only one space gas station then it is a natural monopoly. NASA could try running it itself but since the propellant depot will hope to sell fuel to commercially run space-lines the two boss problem will make management a mess. A depot paid for by NASA but leased out to an operator may work. (See Britain's motorway service stations for a terrestrial equivalent.)

NASA and the FAA can regulate the propellant depot. If the operator misbehaves they can threaten to take it to the Monopolies Commission. I do not know what the Commission will do but the operator is unlikely to like it.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: su27k on 06/10/2017 04:21 am
I don't generally like to rain on space parades, and mods can pull this if they think it doesn't belong. I just feel this entire direction is a waste of time and money, it isn't going to get us to Mars, at least not anytime soon, and wouldn't even do that much to facilitate a moon base or missions that can't be done in other ways. I have trouble seeing the advantages, all this does is add another layer of unnecessary complexity. It sounds like something created to eat budgets. Sorry to be cynical.

NASA has a long term problem. It takes about a decade to develop a major machine. Unlike the Apollo days it can only afford to develop one major machine at a time. Going to Mars will require several new machines. It has chosen to work on an important component - long term life support. ECLSS are needed in capsules, transfer vehicles, spacestations, landers, spacesuits, planetary buildings and manned rovers. It has decided to flight test the ECLSS in a spacestation's habitat.

To quote the article "“In terms of basic functionality, the DSG is being planned to support multiple NASA, commercial, and international objectives,” added the overview. “It would be designed for the deep space environment and would support a crew of 4 for total mission durations of up to 42 days with the Orion vehicle attached."

Please explain how is a 42 days ECLSS qualifies as long term life support?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: redliox on 06/10/2017 04:37 am
Finally content where I can use some of Nathan's amazing L2 renders on the DSG! ;D

ASAP being positive about something!
https://www.nasaspaceflight.com/2017/06/asap-nasas-dsg-stepping-stone-mars/

They are definitely beautiful to look at  :)
I don't generally like to rain on space parades, and mods can pull this if they think it doesn't belong. I just feel this entire direction is a waste of time and money, it isn't going to get us to Mars, at least not anytime soon, and wouldn't even do that much to facilitate a moon base or missions that can't be done in other ways. I have trouble seeing the advantages, all this does is add another layer of unnecessary complexity. It sounds like something created to eat budgets. Sorry to be cynical.

I disagree. Regardless of where we go, we need habitats. I don't think that we are going to Mars any time soon. So this is what we get in the mean time. But this has to be done cheaply. If it's expensive, I agree that it then becomes a distraction.

I agree with you both: it's not really required to get to Mars but it is the only thing NASA could possibly afford in the near future.

My personal opinion is mixed, in addition to what I just mentioned the DSG would be good for the Moon, but it's a distraction for Mars.  What would be better would be to develop an actual landing vehicle for the respective celestial bodies, not so much an ISS 2.0-Luna Deluxe.  Telescopes and experiments can be sent up and act largely autonomously; the Hubble for instance benefited from sporadic human service, but a 24/7 human presence would have compromised its mission (outgassing from life support, ect. were one reason astronomy options for Freedom and then ISS weren't prominent).

As for whether the DSG or DST will materialize...it will largely depend on the success of the SLS firstly.  Secondly, we need to see what the current and future administrations will do (not to get political, but frankly I think Mr Trump is too preoccupied with 'other' matters not to mention I think being explained the impossibility of reaching Mars within a single term threw his interest in NASA away).  I'm only giving it a 40% chance of happening; ARM I'd have given 10% on a generous day for comparison.

I think what could help the DSG's case would be listing a very specific set of objectives it could accomplish.  Testing out self-sufficient and enclosed life support could be considered one, but it shouldn't be the only one.  If its main occupation is near the Moon, include some remote lunar science.  After that, perhaps arrange for servicing other craft is Cislunar space - hypothetically the DSG is supposed to move anywhere, so it could visit a lunar-Lagrange Hubble and refuel and fix it for example, perhaps with a larger tool set than the STS had.  Ensure it is more specific than the ISS yet useful.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/10/2017 04:47 am

To quote the article "“In terms of basic functionality, the DSG is being planned to support multiple NASA, commercial, and international objectives,” added the overview. “It would be designed for the deep space environment and would support a crew of 4 for total mission durations of up to 42 days with the Orion vehicle attached."

Please explain how is a 42 days ECLSS qualifies as long term life support?

After 10 visits that is 10 * 42 = 420 days. More than a year.

The ECLSS in capsules can be serviced every time they return to Earth but the DSG's ECLSS can only expect its consumables to be replaced. NASA hopes to use the same design of ECLSS on its Mars trips.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Chalmer on 06/10/2017 04:48 am
I am in two minds about this DSG.

On the one hand NASA needs to find their next big project after ISS, on the other hand this has some of the hallmarks of a make work program to utilize the SLS/ORION.

I general I like the idea of a way-station where spacecraft’s can refuel and astronauts rest/resupply before the next leg of a journey either to the moon or mars. For that reason, DSG is appealing.

But it should not be a substitute for LEO infrastructure such as a zero-gravity research, tech-demo etc. such as what is happening on ISS. Now commercial might take over this role with after ISS, with NASA as anchor tenant, but NASA would probably still need to initiate a COTS type program for that to happen. 

NASA has forced itself out of LEO in some ways with all its talk of handing over LEO to commercial operators and SLS/ORION is for BLEO. SLS/ORION only justification other than pure pork lies in its superior per launch BLEO capability.

So, given the need to justify and utilize SLS/ORION what to do in BLEO, that is within the flat budget profile?
DSG allows NASA to utilize SLS/ORION to build an infrastructure capacity. A make work program for SLS/ORION that also delivers some permanent value.

The big fear is that a DSG program under the SLS umbrella so to speak will mean its cost will be enormous and ends up never flying or constant being revised since political forces align to keep it going no matter the high costs and low return.  Much like SLS and ORION.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Lars-J on 06/10/2017 05:19 am

To quote the article "“In terms of basic functionality, the DSG is being planned to support multiple NASA, commercial, and international objectives,” added the overview. “It would be designed for the deep space environment and would support a crew of 4 for total mission durations of up to 42 days with the Orion vehicle attached."

Please explain how is a 42 days ECLSS qualifies as long term life support?

After 10 visits that is 10 * 42 = 420 days. More than a year.

The ECLSS in capsules can be serviced every time they return to Earth but the DSG's ECLSS can only expect its consumables to be replaced. NASA hopes to use the same design of ECLSS on its Mars trips.

But if the ECLSS needs to be replenished every 42 days, you certainly aren't getting to Mars. Or am I missing something?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/10/2017 05:28 am
I am in two minds about this DSG.

On the one hand NASA needs to find their next big project after ISS, on the other hand this has some of the hallmarks of a make work program to utilize the SLS/ORION.

I general I like the idea of a way-station where spacecraft’s can refuel and astronauts rest/resupply before the next leg of a journey either to the moon or mars. For that reason, DSG is appealing.

But it should not be a substitute for LEO infrastructure such as a zero-gravity research, tech-demo etc. such as what is happening on ISS. Now commercial might take over this role with after ISS, with NASA as anchor tenant, but NASA would probably still need to initiate a COTS type program for that to happen. 

NASA has forced itself out of LEO in some ways with all its talk of handing over LEO to commercial operators and SLS/ORION is for BLEO. SLS/ORION only justification other than pure pork lies in its superior per launch BLEO capability.

So, given the need to justify and utilize SLS/ORION what to do in BLEO, that is within the flat budget profile?
DSG allows NASA to utilize SLS/ORION to build an infrastructure capacity. A make work program for SLS/ORION that also delivers some permanent value.

The big fear is that a DSG program under the SLS umbrella so to speak will mean its cost will be enormous and ends up never flying or constant being revised since political forces align to keep it going no matter the high costs and low return.  Much like SLS and ORION.


The prototype machines are being developed under Next Space Technologies for Exploration Partnerships (NextSTEP).
https://www.nasa.gov/nextstep (https://www.nasa.gov/nextstep)
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/10/2017 05:31 am

To quote the article "“In terms of basic functionality, the DSG is being planned to support multiple NASA, commercial, and international objectives,” added the overview. “It would be designed for the deep space environment and would support a crew of 4 for total mission durations of up to 42 days with the Orion vehicle attached."

Please explain how is a 42 days ECLSS qualifies as long term life support?

After 10 visits that is 10 * 42 = 420 days. More than a year.

The ECLSS in capsules can be serviced every time they return to Earth but the DSG's ECLSS can only expect its consumables to be replaced. NASA hopes to use the same design of ECLSS on its Mars trips.

But if the ECLSS needs to be replenished every 42 days, you certainly aren't getting to Mars. Or am I missing something?

Tank sizes can be stretched. Also I did not say the ECLSS was replenished each time. I suspect this is an argument that NASA and the contactors are having.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Chalmer on 06/10/2017 06:18 am
I am in two minds about this DSG.

On the one hand NASA needs to find their next big project after ISS, on the other hand this has some of the hallmarks of a make work program to utilize the SLS/ORION.

I general I like the idea of a way-station where spacecraft’s can refuel and astronauts rest/resupply before the next leg of a journey either to the moon or mars. For that reason, DSG is appealing.

But it should not be a substitute for LEO infrastructure such as a zero-gravity research, tech-demo etc. such as what is happening on ISS. Now commercial might take over this role with after ISS, with NASA as anchor tenant, but NASA would probably still need to initiate a COTS type program for that to happen. 

NASA has forced itself out of LEO in some ways with all its talk of handing over LEO to commercial operators and SLS/ORION is for BLEO. SLS/ORION only justification other than pure pork lies in its superior per launch BLEO capability.

So, given the need to justify and utilize SLS/ORION what to do in BLEO, that is within the flat budget profile?
DSG allows NASA to utilize SLS/ORION to build an infrastructure capacity. A make work program for SLS/ORION that also delivers some permanent value.

The big fear is that a DSG program under the SLS umbrella so to speak will mean its cost will be enormous and ends up never flying or constant being revised since political forces align to keep it going no matter the high costs and low return.  Much like SLS and ORION.


The prototype machines are being developed under Next Space Technologies for Exploration Partnerships (NextSTEP).
https://www.nasa.gov/nextstep (https://www.nasa.gov/nextstep)

I know it is, but that does not preclude a politically motivated  (down-) selection of station provider/designer. Or a massive cost+ program. I see NextSTEP more as a way for NASA to get the ball moving without having a fully funded program of record for a DSG.

In any case the DSG would still be beholden to SLS, since that is the rocket that will put it in space, and service it with crews. As such any DSG would have its fate and schedule tied to SLS and ORION.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: AegeanBlue on 06/10/2017 07:24 am
We must look realistically what the HEOMD budget is supposed to support at the end of the next decade:

ISS or its replacement: Despite all the talk about dropping the ISS so as to free money for deep space exploration NASA will not abandon LEO. There is a community that will lobby to ensure that it will keep on having a place and the ability to conduct its experiments. In any case dropping the shuttle did not release tons of money for SLS: The NASA budget reached its Shuttle value only 6-7 years after the last flight. Appropriators used the savings to reduce the deficit rather than redirected it an NASA. The best we can hope is that ISS replacement is cheaper to operate than ISS.

Exploration architecture: That is pretty nebulous so far with DSG being the best option so far. SLS will fly, SpaceX made the mistake of not placing its factory in Alabama. After SLS block II rocket development will take a back stage. The army of engineers needs other challenges. ARM proved too complicated with few fans. The community was willing to take the money, but no one loved the project. 42 days right now does not look much, but I have always understood that the idea is to stretch it to months without resupply. Let's see what will go forward, for now NASA is mostly going by autopilot due to lack of strong direction, let alone large budget
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TaurusLittrow on 06/10/2017 09:58 am

We know that even though SpaceX is being paid to send two humans around the Moon, otherwise they are focused on building interplanetary spacecraft that can start to colonize Mars. So I don't see SpaceX themselves being interested in the DSG. Maybe a SpaceX customer would want to go, but I think there is a limited market for that.


I'm sure SpaceX would be happy to ferry cargo and crew to the DSG if NASA picked up the tab (per the ISS). William Gerstenmaier, who is NASA establishment personified, has given the nod of approval to the notion of a mixed stable of commercial and government rockets and vehicles. “This is a great way to be. I love every one of these rockets. We will figure out some way to use some subset of these as they mature through the industry.” Eventually, extend the current CC/ISS model to the DSG so NASA with its SLS/Orion can focus on Mars.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Chris Bergin on 06/10/2017 01:12 pm
Yep. Gerst hates it when people say "them vs us". He sees everyone as different parts of the same team.

Per the DSG plan. I love it. I love the L2 Gateway and I love this. :)

Great stepping stone approach to deep space human space flight. And building an outpost out there. Heck, *just from a public coolness point of view* (minor, but a point about public support) imagine the photos tweeted from those astros? Those photos from the ISS are probably the most viewed thing relating to NASA etc in the public arena.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TaurusLittrow on 06/10/2017 02:34 pm
Heck, *just from a public coolness point of view* (minor, but a point about public support) imagine the photos tweeted from those astros? Those photos from the ISS are probably the most viewed thing relating to NASA etc in the public arena.

Exactly. I'm (barely) old enough to remember Apollo 8 and where I was when I first saw the grainy BW images of crescent earth. If you can't get exited by HD color images from cislunar space, check your pulse, you may be dead.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 06/10/2017 06:15 pm

To quote the article "“In terms of basic functionality, the DSG is being planned to support multiple NASA, commercial, and international objectives,” added the overview. “It would be designed for the deep space environment and would support a crew of 4 for total mission durations of up to 42 days with the Orion vehicle attached."

Please explain how is a 42 days ECLSS qualifies as long term life support?

After 10 visits that is 10 * 42 = 420 days. More than a year.

The ECLSS in capsules can be serviced every time they return to Earth but the DSG's ECLSS can only expect its consumables to be replaced. NASA hopes to use the same design of ECLSS on its Mars trips.

But if the ECLSS needs to be replenished every 42 days, you certainly aren't getting to Mars. Or am I missing something?

Presumably the ECLSS can be replenished. You don't throw away the DSG after 42 days to be replaced by another one. Attach 12 resupply craft to hard points on the outer shell and use the arm to dock the resupply craft to one of the ports every 42 days. 42 x 13 = 546 days.

But again, even though you could do Mars with DSG, Gerstenmaier indicates that it really is just a test bed for a better craft down the line(DST). The engines and solar panels at the very least need to be tested long duration in the relevant environment. Wear levels on the solar panels in the precise radiological environment is something that needs to be 100% understood. NASA's Space Radiation Laboratory(NSRL) is only an approximation.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 06/10/2017 09:44 pm
The DST is Mars vehicle and its ECLSS will be tested in 1 yr shakedown cruise in cislunar space. The DSG duration limitations are more likely its small habitat space for crew and limited storage.


Sent from my SM-G570Y using Tapatalk

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 06/10/2017 10:09 pm
Yep. Gerst hates it when people say "them vs us". He sees everyone as different parts of the same team.

Per the DSG plan. I love it. I love the L2 Gateway and I love this. :)

Great stepping stone approach to deep space human space flight. And building an outpost out there. Heck, *just from a public coolness point of view* (minor, but a point about public support) imagine the photos tweeted from those astros? Those photos from the ISS are probably the most viewed thing relating to NASA etc in the public arena.
I agree. With the NASA human spaceflight budget being lukewarm for the forseeable future - the DSG near the Moon is about all we can expect, so we should get onboard with it. I like the idea better than putting a truck-sized asteroid into lunar orbit anyway. The conditions out a bit beyond the Moon will be very similar to a cruise across the Solar system - except for the radio time delay. They'll get to truly pioneer decent, long-duration ECLSS and radiation mitigation. And being part of the Earth-Moon system: the DSG would get to travel right around the Solar System anyway, as the Earth and Moon will 'drag' it across millions of kms of space every year.

The crew could tele-operate lunar rovers and sample-return probes in virtual realtime and eventually with some Commercial space cooperation; maybe operate reusable, manned lunar landers as well (eventually). Basically; what's not to like?! I also hope NASA gets the budget and mandate to test and develop large scale SEP - it could be a game-changer.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: AncientU on 06/10/2017 10:11 pm
...

But again, even though you could do Mars with DSG, Gerstenmaier indicates that it really is just a test bed for a better craft down the line(DST). The engines and solar panels at the very least need to be tested long duration in the relevant environment. Wear levels on the solar panels in the precise radiological environment is something that needs to be 100% understood. NASA's Space Radiation Laboratory(NSRL) is only an approximation.

It isn't exploration if this is your standard.  Some risk and unknowns must remain unless another 50 years on planet Earth is your timeline.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 06/12/2017 04:47 pm

DSG repeats the "build it and they will come" NASA human space flight mantra.  But like STS, ISS, and SLS before it, I worry that DSG will be an underutilized and expensive albatross.  I don't see the clear set of deep space research objectives driving DSG's design decisions or an architecture to get to a planetary surface that justifies DSG's existence. 

I also worry that DSG is an unnecessarily large and complex station, requiring its own marching army and multiple launches thru EM-8 (circa 2026 at best) to field -- well beyond the end of the current Administration.

As Napoleon said, when you set out to take Vienna, take Vienna.

If NASA leadership wants to do research on long-duration, human deep space flight, then propose a station beyond the Van Allen Belts that can simulate those missions for hundreds of days at a time starting in the next 4-7 years.

If NASA leadership wants to go back to the Moon, then propose a reasonable human lander to the Administration that can get something done in the next 4-7 years.  Maybe throw in some robotics that can be joysticked from Earth.

If NASA leadership want to put humans on Mars, then get serious about sample return and flight testing some of the necessary transit, EDL, and surface technologies in the next 4-7 years. 

Maybe propose all three and let the Administration pick.  There are reasonable plans and/or capable partners for each outside NASA.  And if the Administration wants all three, then propose terminating SLS and Orion and relying on other domestic HLVs and capsules to free up the necessary funds.

But don't propose spending billions of dollars that SLS and Orion don't leave in the budget to build a station in lunar orbit that:

-- even under the most optimistic schedule, can't be used until the first term of the next Administration;
-- can't simulate long-duration human exploration missions,
-- lacks a defined architecture to get to the surface of the Moon, and
-- lacks an architecture or even technology investments to get to the surface of Mars.

Sure, if you have no direction, no plan to get to any planetary surface, and few resources, DSG is as good as anything else -- and maybe marginally better that ARM -- to give SLS and Orion something to do and maintain the STS infrastructure and workforce.

But that's not what NASA's human space flight enterprise is supposed to be about.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Space Ghost 1962 on 06/12/2017 06:43 pm
Agree that DSG can become an albatross - look at the intense desires to "overbuild" DSG with lots of stupid modules. To be avoided.

But please consider what NASA has in its hands - SLS. And that everyone still wants "firsts", especially "first men on Mars", possibly preceded by "first men at Mars".

So, like playing catch between two as a minimal game, you have two mitts and a baseball. Two DSG's and a DST.
To which you could add a lander.

Polar opposite of Musk's BFR/BFS approach.  Might be hard to consider SLS as a minimalist's approach to Mars, but it is.

How the Moon would factor in is after DSG/DST, then DSG/DST/DSG, you'd be able to test the lander from DSG on the Moon before SEP'ing it off to Mars. And you might land on Mars before Musk does, getting your "first".

So what might keep the govt HSF (possibly all govts BTW ...) from getting irrelevant would be a tight mission focus that could keep it from dithering, due to "competition".

Now, there's no issue (other than diversion of aggregate global resources/focus) to use both DSG's to construct other missions/stations/whatnot nearby - fine, make a line of Bigelow Hotels at Earth/Moon/Mars/wherever, but they are separate entities entirely self-supporting. Perhaps Russia builds its Cislunar station using it, perhaps China does likewise near Mars ... but no more combined ISS nightmares, just "at a distance" support from DSG in case of emergency.

That way you use what you have most effectively.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 06/12/2017 10:32 pm
So, like playing catch between two as a minimal game, you have two mitts and a baseball. Two DSG's and a DST.

If you mean put a DSG in lunar orbit and another DSG in Mars orbit, at that point, it probably makes sense to consider a cycler.  Rendezvous in Mars orbit is an unproven capability and adding them to Mars architectures will cause overall mission risk to jump for some time to come.

Quote
Might be hard to consider SLS as a minimalist's approach to Mars, but it is.

Putting so many resources into a vehicle that will launch so infrequently certainly constrains options.

It's not clear that a Mars surface mission or more than one lunar surface mission a year could be fielded without heavy involvement from other launchers, which begs the question of why bother with SLS.

It also seems to put high-power electric propulsion on the critical path to Mars.  Hopefully that will work out in time, but it should be an enhancer, not an enabler.

Quote
you'd be able to test the lander from DSG on the Moon before SEP'ing it off to Mars.

EDL at Mars is very different from EDL at the Moon.  A Mars lander has to be demonstrated at Mars.

Quote
So what might keep the govt HSF (possibly all govts BTW ...) from getting irrelevant would be a tight mission focus that could keep it from dithering

Tight focus does not seem to be in the cards, unfortunately.

Quote
just "at a distance" support from DSG in case of emergency.

There is some logic in having an independent shelter a little distance from a station.  Rapidly bringing crews all the way back to Earth's surface under emergency conditions (from LEO or lunar orbit) is a risky proposition in itself.  And there are failure modes where that would not be required or desirable.

But a shelter, like insurance, has to be affordable -- a small fraction of the cost of the station (or an emergency crew return vehicle) itself.  Unfortunately, our insurance for ISS cargo/crew and for other domestic HLVs and capsules is many times bigger than those costs.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Space Ghost 1962 on 06/13/2017 04:02 am
So, like playing catch between two as a minimal game, you have two mitts and a baseball. Two DSG's and a DST.

If you mean put a DSG in lunar orbit and another DSG in Mars orbit, at that point, it probably makes sense to consider a cycler.

Nope. Because you have no high delta-v propellant logistics to use such. Cyclers don't handle the delta-v differential well otherwise.

And you have now increased the scope of the problem w/o using what you have well. Your suggestion works backwards.

Quote
Rendezvous in Mars orbit is an unproven capability and adding them to Mars architectures will cause overall mission risk to jump for some time to come.
No different than in Earth or lunar orbit.

Quote
Quote
Might be hard to consider SLS as a minimalist's approach to Mars, but it is.

1)Putting so many resources into a vehicle that will launch so infrequently certainly constrains options.

2)It's not clear that a Mars surface mission or more than one lunar surface mission a year could be fielded without heavy involvement from other launchers, which begs the question of why bother with SLS.

3)It also seems to put high-power electric propulsion on the critical path to Mars.  Hopefully that will work out in time, but it should be an enhancer, not an enabler.

1. You use it because it is available, it advances your mission, and it allows political/industry to renegotiate the new landscape of technology. And if it fails, new launch capability will phase in from three sources that can eventually serve in the same capacity.

2. Logistical support of Mars/lunar DSG's can also be via commercial on long cycle trajectories to pre-position consumables/supplemental payload. The primary function of SLS will be the crew ride and exploration payloads.

3. SEP is/has been the only propulsion technology that has improved enough to allow reasonable mass margins for a near term HSF Mars mission. Short of Musk's approach to allow a much larger mission architecture, which is out of the scope of current plans.

Quote
Quote
you'd be able to test the lander from DSG on the Moon before SEP'ing it off to Mars.

EDL at Mars is very different from EDL at the Moon.  A Mars lander has to be demonstrated at Mars.
Certainly.

But you can test the function of the system's mission architecture, much in the same manner of with Phobos /Deimos. As well as tests of preliminary vehicles flow unmanned earlier to Mars ahead of time, which a) don't have to carry the additional burden of ECLSS/provisions, b) don't have to have DSG's in place, and c) might also not require SLS capabilities to get them there.

Quote
Quote
So what might keep the govt HSF (possibly all govts BTW ...) from getting irrelevant would be a tight mission focus that could keep it from dithering

Tight focus does not seem to be in the cards, unfortunately.
Agreed. But that's the minimum.

Quote
Quote
just "at a distance" support from DSG in case of emergency.

1. There is some logic in having an independent shelter a little distance from a station.  Rapidly bringing crews all the way back to Earth's surface under emergency conditions (from LEO or lunar orbit) is a risky proposition in itself.  And there are failure modes where that would not be required or desirable.

2. But a shelter, like insurance, has to be affordable -- a small fraction of the cost of the station (or an emergency crew return vehicle) itself.  Unfortunately, our insurance for ISS cargo/crew and for other domestic HLVs and capsules is many times bigger than those costs.

1. Apollo/LM was done under the consideration that the American resources of the time would not be left in place before/following the lunar campaign. For various reasons. But when you have a DSG that can hibernate between uses, unlike the "always on" ISS, it becomes the prime contingency instead of Earth return. Nearby help means less scope of capability to reach such contingencies.

2. By keeping the size down of DSG to a fraction of ISS, and because it hibernates, the overhead to maintain capability is a fraction of ISS's costs, which resupply/maintenance is amplified by the lack of these things.

Which is why DSG's aren't "stations". And can't be if they are to be affordable.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: AncientU on 06/13/2017 12:40 pm
...

1. You use it because it is available, it advances your mission, and it allows political/industry to renegotiate the new landscape of technology. And if it fails, new launch capability will phase in from three sources that can eventually serve in the same capacity.

2. Logistical support of Mars/lunar DSG's can also be via commercial on long cycle trajectories to pre-position consumables/supplemental payload. The primary function of SLS will be the crew ride and exploration payloads.

3. SEP/has been the only propulsion technology that has improved enough to allow reasonable mass margins for a near term HSF Mars mission. Short of Musk's approach to allow a much larger mission architecture, which is out of the scope of current plans.
...

1. Not available.  Still many years away from any operations.

2. DSGs (plural)?  First DSG needs 4 SLS flights after EM-1, so late 2020s.  And you think a second will be built?

3. SEP will never be used for a HSF mission, let alone a near-term one.  Improved enough for cargo... maybe the next generation of SEP.  On orbit refueling is the only technology that will get anything to Mars beyond a flag and a couple people to make footprints.

DSG as conceived -- a multi-launch, SLS-only, DRO assembled/fitted out space craft -- will be stillborn.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/13/2017 01:48 pm
{snip}
2. DSGs (plural)?  First DSG needs 4 SLS flights after EM-1, so late 2020s.  And you think a second will be built?

{snip}

4 SLS flights will not needed to launch DSG#2 if NASA does not launch 4 Orions at the same time.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 06/14/2017 12:41 am
The 1st module of DSG may fly on EM2 with unmanned Orion. If this happens then crew of EM3 could deliver habitat module and stay for a while.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Space Ghost 1962 on 06/14/2017 01:18 am
...

1. You use it because it is available, it advances your mission, and it allows political/industry to renegotiate the new landscape of technology. And if it fails, new launch capability will phase in from three sources that can eventually serve in the same capacity.

2. Logistical support of Mars/lunar DSG's can also be via commercial on long cycle trajectories to pre-position consumables/supplemental payload. The primary function of SLS will be the crew ride and exploration payloads.

3. SEP/has been the only propulsion technology that has improved enough to allow reasonable mass margins for a near term HSF Mars mission. Short of Musk's approach to allow a much larger mission architecture, which is out of the scope of current plans.
...

1. Not available.  Still many years away from any operations.
Like any comparable LV in payload weight/volume.

Quote
2. DSGs (plural)?  First DSG needs 4 SLS flights after EM-1, so late 2020s.  And you think a second will be built?
Or ... suppose you build DSG ... qualify DST on cislunar/NEO/other flights ... use it to build another station, possibly for another govt/corporation.

Then you "rent" just the time you use for missions on the other station ... and SEP the DSG to Mars (why you keep it minimal). So you build/maintain just one of them. And, its all checked out for long duration.

Quote
3. SEP will never be used for a HSF mission, let alone a near-term one.  Improved enough for cargo... maybe the next generation of SEP.  On orbit refueling is the only technology that will get anything to Mars beyond a flag and a couple people to make footprints.
SEP is the only propulsion technology that can/will be used by govt for both crew and cargo.

That's the Boeing proposal. Read it.

Quote
DSG as conceived -- a multi-launch, SLS-only, DRO assembled/fitted out space craft -- will be stillborn.
Suggest perhaps overblown, but it is a viable means of getting to Mars soonest.

Will it be "soonest"? Have no idea. Trying to predict govts/politics is out of my ken (and likely theirs).

But it is feasible. More so in many ways than BFR/BFS (much more risk to be retired, economics yet to work).

IMHO - best approach would be more aggressive strategy on the exploration vehicles earlier, a greater use of the ISS for assembly/check-out (personally flying SLS w/o Orion/EUS/IUS makes significant sense including economics, first flight, and reasonable flight rate considerations for the initial sequence of flights). Matures SLS/DSG ahead of crew.

Then spiral out the assembled, smaller DSG and autonomously dock a full-up Orion, resupply handled robotically (as it should be for Mars). DST on station following. Second Orion mission as crewed with checkout of DST.

All propellants/consumables via commercial/partner launches.

More bang for the buck.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 06/14/2017 11:46 am
I used to think a Mir/Zvezda core module attached to an ISS multi-docking Node would make a good Deep Space Gateway station. It has proven life support systems and refuelability and with improved thermal and radiation shielding could handle the constant sunlight of Cislunar space well. I've attached a picture of the very early configuration of ISS as Zarya/Node 1. But imagine the same type of Node attached to the larger Mir/Zvezda module. This would be the basis of a decent Gateway station, I feel, though I don't know if Russia can still make this type of spacecraft. The duo of core module and Node could be sent out beyond the Moon either with chemical propulsion or a combined Chemical/SEP propulsion bus. I don't know what Russia would charge for another one of these modules, or how long they would take to build it (they're not great with schedules) but this combination would mass about 35 tons.

To send the Core Module out beyond the Moon; first, it is placed in orbit by a Proton launcher. Then, a modified Falcon Heavy upper stage could be placed into orbit near it, with about 55 tons of propellants left over from ascent. On top of the stage could be a docking mechanism compatible with the Russian module. The Corestage is commanded to dock with it and the Falcon stage boosts it on a low energy trajectory to the chosen Cislunar location. The Node module could be taken to it by a crewed Orion spacecraft later on.

If not the actual, above configuration - then something similar. There is no need to build another ISS scale station, this time in deep Cislunar space.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Space Ghost 1962 on 06/14/2017 05:28 pm
Suggest we are past so much mass/ineffective ISS modules.

What do you most need in a DSG? Think about Mars arrival - what do you want at "base camp", to support surface descent/ascent/return ... that you don't want to carry along with you on DST. And ... a DSG whose logistics to maintain when idle (99% of the time) is least.

Mars robots have already a significant record accumulated of operation. A robotically maintained/resupplied/repaired station with longevity and substantial solar power/EP/"stationkeeping"/orbital maneuvering margin (to Phobos/Deimos) is the minimum, and the expectation of normal operation. Because that's where the basic economics of DSG operations would come from - nothing more than a glorified version of MAVEN/Curiosity, what we have there already, just with scaled up SEP and 5-10x longer life. And, if this basis module to the DSG were to start to deteriorate (like equipment on the ISS), you schedule your ground spare for flight immediately (and if it doesn't fail, it's a "hot" standby).

That's the minimum.

Next, likely you want an airlock / tools / "arm" for extraordinary repairs, meant to be used less than once a year, meaning not for  FRFs etc. Keeping this useful but constrained would be difficult (you'd likely incrementally "grow" this capability on every mission).

Propellant/consumables/components reserves for extraordinary needs/leaks/spoilage/whatever.

Docking capability for N > 3 vehicles (two plus automated resupply). In the worst, worst case, the ability to always gain access through robotic vehicle access would be preserved, potentially launched at unfavorable times and possibly through peculiar conditions/windows.

That's it.

Specifically, no hab and little persistent ECLSS/human volume, not much more than a capsule. Your transit vehicle is the one that needs that, the one that will be used longest, have the most wear/tear.

This is why such dumb notions as Bigelow modules are worst solutions ever. Your astros shouldn't spend anytime with DSG at all - that wears down a hard to reach/maintain asset for no gain. Stations are a really bad idea for exploration. Like rovers, we need to have exploration assets on the move at all times.

So DSG's cannot be a burden but instead refuge/repair/resupply/"plan B". Most of the time cold storage.

Spend your Bigelow module time/resources on exploration vehicles like landers/rovers/MMSEV's etc. Something that generates a research product, possibly part-time used HSF, rest robotic. Think different.

Leave the Bigelow module/etc to what they do best - resorts. Govt does not need to fund any Trump towers in space. That's not exploration - leave it to commercial space, where it always belonged.

Possibly research labs in space fit for materials/other research. Also a commercial activity past the ISS "one-shot".
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 06/14/2017 11:10 pm
I too don't believe the Bigelow modules will do for a Gateway Module. They're far too unproven at this stage to rely on. But Gateway modules will have to be structurally robust - which would mean aluminum. I'd never advocate just plunking surplus ISS modules at Lagrange points - though the ISS modules are proven spacecraft hulls. Continually starting from a clean sheet design could bring up as many costly delays as it would new operational features and improvements. Double-edged sword, I guess.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: envy887 on 06/14/2017 11:32 pm
I don't buy for a minute that aluminum vessels are structurally better than a well designed composite inflatable.

However, Bigelow habs are focused on habitable volume, which as pointed out above isn't the primary need in a DSG.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 06/15/2017 12:04 am
I didn't say better - I said proven.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/15/2017 07:19 am
I didn't say better - I said proven.

Operate a prototype gateway in LEO for a few years and composite inflatables will also be proven.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 06/15/2017 08:03 am
Good! Let's see them get on with it then... I hope by 2021 & beyond, we're all still not waiting. Though I would urge us all not to have blind faith in any particular structural substance or configuration. Some people are treating composite and/or inflatable modules as a given - and suggesting anything else seems to make that same folk bizzarely upset. We'll just have to wait and see.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: su27k on 06/17/2017 04:33 am

To quote the article "“In terms of basic functionality, the DSG is being planned to support multiple NASA, commercial, and international objectives,” added the overview. “It would be designed for the deep space environment and would support a crew of 4 for total mission durations of up to 42 days with the Orion vehicle attached."

Please explain how is a 42 days ECLSS qualifies as long term life support?

After 10 visits that is 10 * 42 = 420 days. More than a year.

Where does 10 visits come from? There are only 6 Orion flights (EM-1 to 5 and EM-7) before DST one year shakedown mission, and only 4 Orion flights (EM-3 to 5 and EM-7) after Habitation Module is deployed, so you only gets to run ECLSS 4 * 42 = 168 days before you need to run ECLSS for a year. And you only run ECLSS 42 days a time, so you can't test whether it can be run continuously without breakdown.

A multi-year continuous ECLSS test can easily be done via ISS, so why run it in DSG? This is the whole problem with this DSG plan. If you want to test long term ECLSS then just focus on ECLSS, if you want to build DST then build it, drag DSG into it will only mean less funding for things actually matter.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Oli on 06/17/2017 08:10 am
This is the whole problem with this DSG plan. If you want to test long term ECLSS then just focus on ECLSS, if you want to build DST then build it, drag DSG into it will only mean less funding for things actually matter.

The point of DSG is to give SLS/Orion something to do until DST is ready. Experience gained is a bonus.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 06/17/2017 09:03 am
This is the whole problem with this DSG plan. If you want to test long term ECLSS then just focus on ECLSS, if you want to build DST then build it, drag DSG into it will only mean less funding for things actually matter.

The point of DSG is to give SLS/Orion something to do until DST is ready. Experience gained is a bonus.
Plus international partners want it as it get them closer to moon.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 06/17/2017 10:09 am

To quote the article "“In terms of basic functionality, the DSG is being planned to support multiple NASA, commercial, and international objectives,” added the overview. “It would be designed for the deep space environment and would support a crew of 4 for total mission durations of up to 42 days with the Orion vehicle attached."

Please explain how is a 42 days ECLSS qualifies as long term life support?

After 10 visits that is 10 * 42 = 420 days. More than a year.

Where does 10 visits come from? There are only 6 Orion flights (EM-1 to 5 and EM-7) before DST one year shakedown mission, and only 4 Orion flights (EM-3 to 5 and EM-7) after Habitation Module is deployed, so you only gets to run ECLSS 4 * 42 = 168 days before you need to run ECLSS for a year. And you only run ECLSS 42 days a time, so you can't test whether it can be run continuously without breakdown.
{snip}
10 is a nice simple round number. The EM-n flights are unlikely to be the only visits to the DSG.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TaurusLittrow on 06/17/2017 12:20 pm
Long-term reliable ECLSS is one issue for DSG but equally pressing are human factors esp. radiation exposure. I believe one or more Apollo missions missed significant (potentially fatal) solar particle events (SPE) during their short forays BEO. One large SPE occurred between Apollo 16 and 17.

The DSG will need some type of radiation "storm shelter" on-board for the crew. Given that DSG will include a propulsion module, is using the moon as a shield during an SPE by re-positioning the outpost an option?  Any public sources on this topic specifically for DSG?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Oli on 06/17/2017 01:33 pm
This is the whole problem with this DSG plan. If you want to test long term ECLSS then just focus on ECLSS, if you want to build DST then build it, drag DSG into it will only mean less funding for things actually matter.

The point of DSG is to give SLS/Orion something to do until DST is ready. Experience gained is a bonus.
Plus international partners want it as it get them closer to moon.

They have no money to land on the moon.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 06/17/2017 04:33 pm
No country except maybe China can afford to fund a lunar architecture with earth as your starting point. Apollo did it at huge cost and Constellation tried.

If the starting point is 2.5km/s from lunar surface and only thing required is lander capable of 5-5.5km/s then develop costs are lot lower. A lot easier sell especially if it could be operation within 5yrs of approval. I suspect there will be cargo landers operating by time DSG is in place, making development of human lander more affordable than it is now.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 06/18/2017 04:52 pm
This is the whole problem with this DSG plan. If you want to test long term ECLSS then just focus on ECLSS, if you want to build DST then build it, drag DSG into it will only mean less funding for things actually matter.

The point of DSG is to give SLS/Orion something to do until DST is ready. Experience gained is a bonus.
Plus international partners want it as it get them closer to moon.

They have no money to land on the moon.

Applying the funding split ratio between the Apollo LM and the CSM to Orion and a new lunar lander, a lander would require funding of about $800 million per year.

Funding by agency
NASA: ~$19.6 billion
ISRO: ~$1.2 billion
ESA: ~$6.4 billion
CNSA: ~$1.3 billion
JAXA: ~$2 billion
Roscosmos: ~$3.2 billion
KARI: $583 million

In reality, any of a half dozen space agencies could afford it. Probably including south korea's if that was their only project.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Zed_Noir on 06/18/2017 05:20 pm
No country except maybe China can afford to fund a lunar architecture with earth as your starting point. Apollo did it at huge cost and Constellation tried.

If the starting point is 2.5km/s from lunar surface and only thing required is lander capable of 5-5.5km/s then develop costs are lot lower. A lot easier sell especially if it could be operation within 5yrs of approval. I suspect there will be cargo landers operating by time DSG is in place, making development of human lander more affordable than it is now.

Don't think even China can set up an Earth based architecture with their currently planned space vehicle development program. IMO

However the folks from Hawthorne can in theory set up a system of propellant depots at LEO, L4/L5 & HLO  locations with the ITS tankers as both depots and propellant transfer vehicle plus act as Lunar lander. Of course this system does not need the SLS, Orion, DSG and inspace SEP tug. So it will be a race for NASA to field a DSG before the ITS tanker enters servuce. Presuming the ITS development program is happening & somewhat on time.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 06/18/2017 05:42 pm
They have no money to land on the moon.

Applying the funding split ratio between the Apollo LM and the CSM to Orion and a new lunar lander, a lander would require funding of about $800 million per year.

$800M/year for how many years? What are you assuming the cost of a new lunar lander would be?

Plus, Oli did not state they couldn't afford a lander, but that there was no money to land on the Moon. Which to me means the funding for the entire effort, not just a transportation element.

Quote
Funding by agency
NASA: ~$19.6 billion
ISRO: ~$1.2 billion
ESA: ~$6.4 billion
CNSA: ~$1.3 billion
JAXA: ~$2 billion
Roscosmos: ~$3.2 billion
KARI: $583 million

In reality, any of a half dozen space agencies could afford it. Probably including south korea's if that was their only project.

You are assuming that each of those space agencies could easily substitute a $800M/year lander program for programs they are already committed to working on - which ignores the constituents of those other programs.

As to the U.S. all monies come from the general fund, and there is no constitutional limit on how much money Congress can allocate to NASA. If it's important Congress will fund it - we've already seen that Congress is OK for deficit spending.

Same with the DSG/DST. If Congress thinks it's important to have a national asset in cislunar space, then they will fund it. That won't happen in the FY2018 fiscal year though, so yet again payloads and missions for the SLS and Orion will not be committed to - not sure how much longer that can happen before it's recognized as a trend...
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 06/18/2017 06:06 pm
They have no money to land on the moon.

Applying the funding split ratio between the Apollo LM and the CSM to Orion and a new lunar lander, a lander would require funding of about $800 million per year.

$800M/year for how many years? What are you assuming the cost of a new lunar lander would be?

Plus, Oli did not state they couldn't afford a lander, but that there was no money to land on the Moon. Which to me means the funding for the entire effort, not just a transportation element.

Quote
Funding by agency
NASA: ~$19.6 billion
ISRO: ~$1.2 billion
ESA: ~$6.4 billion
CNSA: ~$1.3 billion
JAXA: ~$2 billion
Roscosmos: ~$3.2 billion
KARI: $583 million

In reality, any of a half dozen space agencies could afford it. Probably including south korea's if that was their only project.

You are assuming that each of those space agencies could easily substitute a $800M/year lander program for programs they are already committed to working on - which ignores the constituents of those other programs.

As to the U.S. all monies come from the general fund, and there is no constitutional limit on how much money Congress can allocate to NASA. If it's important Congress will fund it - we've already seen that Congress is OK for deficit spending.

Same with the DSG/DST. If Congress thinks it's important to have a national asset in cislunar space, then they will fund it. That won't happen in the FY2018 fiscal year though, so yet again payloads and missions for the SLS and Orion will not be committed to - not sure how much longer that can happen before it's recognized as a trend...

Ohh, I think DSG is already in the process of being acquired. For instance, engines:

Quote
Aerojet Rocketdyne, a subsidiary of Aerojet Rocketdyne Holdings, Inc. (NYSE:AJRD), has signed a $67 million cost-plus fixed fee (plus performance incentive) contract with NASA to develop a high-power electric propulsion system that will enable key elements of NASA's plans for exploration of cis-lunar space and Mars.

Under the Advanced Electric Propulsion System (AEPS) contract, the Aerojet Rocketdyne team will develop, qualify and deliver five 12.5 kilowatt Hall thruster subsystems including thrusters,
http://www.rocket.com/article/aerojet-rocketdyne-signs-contract-develop-advanced-electric-propulsion-system-nasa

ARM is in the process of being shut-down and these will be transferred to DSG to act as 4 flight units and one spare.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: punder on 06/18/2017 06:25 pm
Luke, it's a trap!

DSG will neatly close the USG/contractor "business case." Deep space destination for US HSF: Check. Big flashy rocket and spacecraft for transportation thereto: Check. Throw in some low-mass science experiments on each flight, and... what more could you want? Or more precisely, what more could you get? Because for the next 20 years, your entire budget will be barely adequate for maintaining the DSG and building/launching/disposing of its transportation system.

And that will be that.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: AncientU on 06/20/2017 01:53 pm
Luke, it's a trap!

DSG will neatly close the USG/contractor "business case." Deep space destination for US HSF: Check. Big flashy rocket and spacecraft for transportation thereto: Check. Throw in some low-mass science experiments on each flight, and... what more could you want? Or more precisely, what more could you get? Because for the next 20 years, your entire budget will be barely adequate for maintaining the DSG and building/launching/disposing of its transportation system.

And that will be that.

Ars Technica article agrees:
Quote
The Journey to Mars seems to be pretty much dead

Quote
On Friday, the space agency released what it called a "mid-year report" on NASA five months into the presidency of Donald Trump. The nearly five-minute video...

Quote
...the video makes no mention of Mars at all, the planet where NASA has by far the most assets of any world other than Earth—several rovers and orbiters studying the red planet's surface and atmosphere for clues of its past habitability for life. NASA has made a number of significant discoveries about Mars this year, such as confirming the absence of carbonate in rocks there. But none merit mention in the promotional video.
Journey to Mars

The red planet is also excluded from the video's discussion when it comes to human exploration. Prior to this year, the agency's off-stated goal was sending humans to Mars in the 2030s. This "Journey to Mars" had been a frequent talking point for then-administrator Charles Bolden and other agency leaders. They talked about the Space Launch System rocket and Orion spacecraft as key components of this mission.

https://arstechnica.com/science/2017/06/the-journey-to-mars-seems-to-be-pretty-much-dead/
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 06/21/2017 01:17 pm
SLS/Orion always seemed much more a 'Moon Rocket' and spaceship to me. A lunar gateway station, with or without any Mars endgame in sight could be a good place to base and service/refuel a reusable lunar lander craft. If the Lander is a Commercially-competed craft or a joint venture between NASA and it's partners... Seems to me a better way of doing things than the purely Constellation modus-operandi.

As I've liked to say before: America could provide the Orion 'Mothership' and the heavy lifter (SLS and/or others) and a NASA/Commercial co-op or ESA/JAXA partnership could provide the reusable Lunar Lander (2,3 or 4 Astronauts). Have the Lander be either a crew or cargo version - a bit like Soyuz/Progress as the two 'flavors' it now comes in. Commercial space entities could compete for cargo deliveries to the Gateway station, as they did to ISS. Also - the Orion could bring a 'Tanker Module' of propellants for the Lander with each crew it brings to the Gateway Station. With Block SLS 1B; Orion could bring 10 tons of propellants for a Lander. With the Block 2 - about 20 tons.

The crew and cargo missions to the Moon could rely on a best-case scenario of the SLS flight rate; which would be 3 or 4 flights per year. With 3x flights - two could be crewed and one could be cargo only. This could allow one 'Sortie' manned mission and one longer duration mission, using the equipment and consumables of the cargo lander. Allowing for an Outpost buildup, the missions could be increased to 2x longer duration Outpost flights per year after a 'simple' Outpost has been established. It would make sense to have the Outpost be a NASA/ESA/JAXA partnership; joined by Commercial Space entities. After a few years of Outpost and Gateway station missions - I consider the Gateway to be the natural successor to ISS - considerable experience in deep space manned mission exploration operations would be accumulated. And the reach for Mars would be happening all in good time; with or without the cooperation of Commercial Space, such as the Musk dream of Mars colonization. Of course - the Gateway does not need to be a 450 ton behemoth at DRO or a Lagrange Point. Something closer to Mir or the projected Chinese station should suffice.

In time, the SLS/Orion system could be supplanted and then superseded by more modern, efficient and more fully reusable space transportation systems. I still believe commercial space entities such as SpaceX and Blue Origin are going to one day hit their stride in a spectacular fashion. Call it faith-based, if you like. And I'm fully aware that everything I just wrote above is best-case scenario in nature. If it happens at all; it will be a slow variation on what I've written. :) :(
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: eric z on 06/21/2017 01:55 pm
 Matt, Great minds must think alike, I couldn't have said it better myself! 8) I notice Stephen Hawking is calling for a return to the moon, too. [Today's Washington Post]
Seriously, I could differ a bit here and there, but you are definitely nailing the issue. Here at NSF I respectfully feel that collectively people can lose sight of the forest for all the trees sometimes. Without a lander-element this is going to get old really fast, IMHO. DSG/H are parts of a plan; not really a plan in and of itself.
 Congress?Admin bigshots need to say to NASA--"We're moving outta here; first phase is to resume manned exploration of different lunar sites leading promptly towards 2 or 3 outposts; with all needed lunar-orbit support, comm sats, etc, etc. The asteroid/Mars-moon thing is running almost simultaneously [hey, I just learned how to use my spell-checker! ::)] and by golly we WILL land there during the early 30s!" NASA leads but incorporates international and commercial as much as possible--Stop Talking and Powerpointing and get rolling already. Fly,Fly Fly--Take Mr. Musk up on his offer to give slots to NASA people; hell he's got one in the corp now! Let the urgency of the good old days be rekindled, but stop micromanaging everything! Yes, kiddies the budget needs a big plus-up; but we should demand much greater results. Better/faster for the next 20-30 years; forget cheaper. Space is NOT the area to get cheapskate with anymore-once we get established more out there things can settle into their more normal economic state--I truly feel we are rushing a false "commercialism/privatize" mentality very inorganically these days instead of a massive, almost war-like all-out push outwards as was envisioned when I was running around making a wooden Gemini capsule in my back yard! Enough with the studies and commissions and white papers already!
  Don't get me wrong, though. Of course reusability and the other cutting-edge advancements of New Space have a huge role to play in what I'm talking about. Smarter minds than me can figure out all this. All I'm trying to say is: In the short-mid term use all the assets we  have to get jump-started. One last point; I feel strongly that the USG has every right, thru NASA or other entities to own space stations, bases, spaceships, etc. for the good of all our people: No one, well hopefully no-one, disputes having National Labs, NIH, etc. but I know this isn't a very popular viewpoint here sometimes...A strong government-led push is what got all this going in the first place, with the great support of industry, of course.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Khadgars on 06/21/2017 10:38 pm
No country except maybe China can afford to fund a lunar architecture with earth as your starting point. Apollo did it at huge cost and Constellation tried.

If the starting point is 2.5km/s from lunar surface and only thing required is lander capable of 5-5.5km/s then develop costs are lot lower. A lot easier sell especially if it could be operation within 5yrs of approval. I suspect there will be cargo landers operating by time DSG is in place, making development of human lander more affordable than it is now.

China is piling up debt faster than we are, they wouldn't be able to afford it either.  The DSG as you pointed out makes a lot of sense for a one off development lander, a lot easier to get from lunar orbit to the lunar surface.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 06/23/2017 05:59 am
No country except maybe China can afford to fund a lunar architecture with earth as your starting point. Apollo did it at huge cost and Constellation tried.

If the starting point is 2.5km/s from lunar surface and only thing required is lander capable of 5-5.5km/s then develop costs are lot lower. A lot easier sell especially if it could be operation within 5yrs of approval. I suspect there will be cargo landers operating by time DSG is in place, making development of human lander more affordable than it is now.

China is piling up debt faster than we are, they wouldn't be able to afford it either.  The DSG as you pointed out makes a lot of sense for a one off development lander, a lot easier to get from lunar orbit to the lunar surface.

Of course China can afford it - it would only be a small part of their already large national debt.

We here in the U.S. can afford it too. There is no constitutional limit on how much money NASA gets.

All that the U.S., China, and any other nation needs is a "need" to go to the Moon. A justification to spend money on doing that as opposed to whatever other priorities they have here on Earth. Which is not a new situation, and is why the Constellation program was so easy to kill - going to the Moon was no longer a priority for the U.S. Government in 2010.

Does anyone think that situation has changed?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 06/23/2017 06:03 am
Not much... But it should. Leave Mars to Elon, I say. When and if he's ready to go - if he and his investors want some technical and infrastructure help; he can only say no, but offer it when the time comes.

And SLS/Orion are not strictly needed for Lunar operations - but it is a far better use for them than Mars at this point.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: AncientU on 06/23/2017 02:22 pm
No country except maybe China can afford to fund a lunar architecture with earth as your starting point. Apollo did it at huge cost and Constellation tried.

If the starting point is 2.5km/s from lunar surface and only thing required is lander capable of 5-5.5km/s then develop costs are lot lower. A lot easier sell especially if it could be operation within 5yrs of approval. I suspect there will be cargo landers operating by time DSG is in place, making development of human lander more affordable than it is now.

China is piling up debt faster than we are, they wouldn't be able to afford it either.  The DSG as you pointed out makes a lot of sense for a one off development lander, a lot easier to get from lunar orbit to the lunar surface.

Of course China can afford it - it would only be a small part of their already large national debt.

We here in the U.S. can afford it too. There is no constitutional limit on how much money NASA gets.

All that the U.S., China, and any other nation needs is a "need" to go to the Moon. A justification to spend money on doing that as opposed to whatever other priorities they have here on Earth. Which is not a new situation, and is why the Constellation program was so easy to kill - going to the Moon was no longer a priority for the U.S. Government in 2010.

Does anyone think that situation has changed?

China has a need: prestige.  To be the only Nation that has the capability to go to the Moon would have huge propaganda value for China.  If it offers to partner with ESA for a Moon Village, they can claim de facto leadership in space.

Assuming that this scenario unfolds, the USG can cede this to China -- or make it a priority again.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 06/23/2017 04:46 pm
Since a lunar lander came up here with some debate about whether other countries could afford a lander...some new information (to me) about European interest in the lander component.

Quote
In the meantime, Europe is advancing its plans for a large, robotic Moon lander closely associated with the Deep Space Gateway. The lander is expected to collect lunar soil samples and shoot them back to the station, where they can be delivered back to Earth by astronauts. The lander might also include a rover that would embark on what might become a record-breaking journey across the lunar surface, toward Amundsen crater near the Moon’s south pole.

The European effort, known by some as HLEPP, the Human Lunar Exploration Precursor Program, would pave the way for a larger crewed lander that could be based at the Deep Space Gateway. At the international partner meeting, engineers confirmed the capability of the station to support human expeditions to the surface. However, the station apparently would not be able to descend to low-lunar orbit, which would be the most convenient option for staging lunar landings.
http://www.planetary.org/blogs/guest-blogs/2017/20170607-iss-partners-dsg.html
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 06/23/2017 07:56 pm
some new information (to me) about European interest in the lander component.

ESA has had a low-level lunar lander effort ongoing for some time.  This article dates to 2009, for example:

https://www.researchgate.net/publication/234503467_An_ESA_precursor_mission_to_human_exploration_of_the_Moon

The question is whether the lunar lander effort can get enough traction to obtain substantial funding from ESA member governments and ramp up.  Even with a lunar advocate like Worner at the Director-General's helm the past couple years, there doesn't seem to be much positive budget movement in this direction.

Maybe the DSG will change that.  But even the DSG doesn't have funding in the current budget before Congress, so any lunar plans will probably remain at these informal, low-level interagency discussions for at least a couple more years.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 06/23/2017 08:04 pm
Read price tag of $1.5B to develop 2 stage robotic lander. 2nd stage came back to DSG with sample. Could be reused with new 1st stage.
Their R&D might be better spent on using commercially available GLXP landers. If launched from DSG some could do a sample return. Moon Express should be capable of round trip returning <10kg.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Robotbeat on 06/24/2017 05:22 am
No country except maybe China can afford to fund a lunar architecture with earth as your starting point. Apollo did it at huge cost and Constellation tried.

If the starting point is 2.5km/s from lunar surface and only thing required is lander capable of 5-5.5km/s then develop costs are lot lower. A lot easier sell especially if it could be operation within 5yrs of approval. I suspect there will be cargo landers operating by time DSG is in place, making development of human lander more affordable than it is now.

China is piling up debt faster than we are, they wouldn't be able to afford it either.  The DSG as you pointed out makes a lot of sense for a one off development lander, a lot easier to get from lunar orbit to the lunar surface.
China just paid a Ukrainian company to modernize the Soviet lunar lander design and give them the plans. China could easily beat us back to the Moon as we seem to be pouring all our money into an oversized launcher and capsule. At least for the Program of Record.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Lars-J on 06/24/2017 06:02 am
China is not going to "beat us" to anything in space. Their human spaceflight pace in the last decade has been a snails pace (being generous) - they only spend the bare minimum to make slow progress. They are not going to start a race anytime soon, so don't count on them creating a race to the moon.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 06/24/2017 06:02 am
Isn't the Soviet lander a bit of a too-basic, one man design?!
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 06/24/2017 06:31 am
All that the U.S., China, and any other nation needs is a "need" to go to the Moon. A justification to spend money on doing that as opposed to whatever other priorities they have here on Earth. Which is not a new situation, and is why the Constellation program was so easy to kill - going to the Moon was no longer a priority for the U.S. Government in 2010.

Does anyone think that situation has changed?

China has a need: prestige.

I see no evidence of that, especially since China's space plans are progressing slowly. If anything they are focusing their "exploration" money on building up their presence in the South China Sea, which has a much larger prestige and economic impact than going to the Moon would have.

Quote
To be the only Nation that has the capability to go to the Moon would have huge propaganda value for China.

Maybe. Although isn't it likely that Elon Musk will be on Mars before China lands on our Moon? And if the BFR/BFS combo can land on Mars, then landing on our Moon will be doable - and likely far more impressive than anything China can build. Already China's expendable rockets are looking pretty antiquated, even the new Long March 5.

Quote
If it offers to partner with ESA for a Moon Village, they can claim de facto leadership in space.

Well, except for that guy named Elon Musk. Who is going to Mars. In a giant reusable spaceship.

Quote
Assuming that this scenario unfolds, the USG can cede this to China -- or make it a priority again.

Just because the U.S. Government may not want to send U.S. Government employees back to our Moon doesn't mean we are "ceding" our Moon to anyone. Just like we didn't "own" our Moon after landing on it, neither will anyone else.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: guckyfan on 06/24/2017 09:30 am
China is not going to "beat us" to anything in space. Their human spaceflight pace in the last decade has been a snails pace (being generous) - they only spend the bare minimum to make slow progress. They are not going to start a race anytime soon, so don't count on them creating a race to the moon.

Yes they are slow. But at least they are moving forward. Who else does that?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: AncientU on 06/24/2017 09:47 am
All that the U.S., China, and any other nation needs is a "need" to go to the Moon. A justification to spend money on doing that as opposed to whatever other priorities they have here on Earth. Which is not a new situation, and is why the Constellation program was so easy to kill - going to the Moon was no longer a priority for the U.S. Government in 2010.

Does anyone think that situation has changed?

China has a need: prestige.

I see no evidence of that, especially since China's space plans are progressing slowly. If anything they are focusing their "exploration" money on building up their presence in the South China Sea, which has a much larger prestige and economic impact than going to the Moon would have.

Quote
To be the only Nation that has the capability to go to the Moon would have huge propaganda value for China.

Maybe. Although isn't it likely that Elon Musk will be on Mars before China lands on our Moon? And if the BFR/BFS combo can land on Mars, then landing on our Moon will be doable - and likely far more impressive than anything China can build. Already China's expendable rockets are looking pretty antiquated, even the new Long March 5.

Quote
If it offers to partner with ESA for a Moon Village, they can claim de facto leadership in space.

Well, except for that guy named Elon Musk. Who is going to Mars. In a giant reusable spaceship.

Quote
Assuming that this scenario unfolds, the USG can cede this to China -- or make it a priority again.

Just because the U.S. Government may not want to send U.S. Government employees back to our Moon doesn't mean we are "ceding" our Moon to anyone. Just like we didn't "own" our Moon after landing on it, neither will anyone else.

So you thing the USG with a bigger space budget than the rest of the world will just sit this one out?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: darkenfast on 06/25/2017 07:04 am
Maybe we don't "own" the Moon, but that doesn't mean a country like China can't come along and treat it just as they have the South China Sea.   Their only claim there is that they have installed military installations and therefore, it's theirs.  If China feels that they have a reason to claim a chunk of space and that no one has the backbone to stand up to them, then they will claim it. 
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Oli on 06/25/2017 10:29 am
China has a need: prestige.

There are other far cheaper ways to gain prestige than to repeat a manned lunar landing.

Curiosity was prestigious for NASA, Rosetta for ESA. Those so-called flagship science missions are the future of prestige in spaceflight. In contrast to human spaceflight there are still plenty of targets. China can do something new instead of just copying what the US has done half a century ago.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Lars-J on 06/25/2017 04:08 pm
China is not going to "beat us" to anything in space. Their human spaceflight pace in the last decade has been a snails pace (being generous) - they only spend the bare minimum to make slow progress. They are not going to start a race anytime soon, so don't count on them creating a race to the moon.

Yes they are slow. But at least they are moving forward. Who else does that?

Pretty much everyone? And are you blind to the progress in this country? (Commercial space/crew on top of what NASA is doing)
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: guckyfan on 06/25/2017 06:39 pm

Pretty much everyone? And are you blind to the progress in this country? (Commercial space/crew on top of what NASA is doing)

I don't see NASA moving forward. And I did not want to mention SpaceX.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: redliox on 06/25/2017 06:50 pm
Do we have any guesses where the DSG will ultimately be placed?  Specifically as in what type of lunar orbit or Lagrange point.  I assume NASA is still eyeing either high elliptical or one of those DRO variations.

I ask this because it'll influence the needs of a future (potentially reusable) lunar lander; closer to the moon the less fuel needs.  I furthermore refer to the needs of a crewed lander; a cargo lander would probably just be sent one-way to Luna itself from Earth.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 06/25/2017 07:37 pm
Do we have any guesses where the DSG will ultimately be placed?  Specifically as in what type of lunar orbit or Lagrange point.  I assume NASA is still eyeing either high elliptical or one of those DRO variations.

I ask this because it'll influence the needs of a future (potentially reusable) lunar lander; closer to the moon the less fuel needs.  I furthermore refer to the needs of a crewed lander; a cargo lander would probably just be sent one-way to Luna itself from Earth.
NRO is favoured at present. See link on orbit info. NB DSG can move between orbits while vacant, crew missions could visit it at NRO followed by EML2 the next year.

http://spirit.as.utexas.edu/~fiso/telecon/Whitley_4-13-16/
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 06/25/2017 07:54 pm
Just because the U.S. Government may not want to send U.S. Government employees back to our Moon doesn't mean we are "ceding" our Moon to anyone. Just like we didn't "own" our Moon after landing on it, neither will anyone else.

So you thing the USG with a bigger space budget than the rest of the world will just sit this one out?

I'm not sure what there is to "sit out", since the solar system is a pretty big place.

For instance, a medium-sized private company in California is planning on colonizing Mars. Does that mean if China doesn't have plans for sending humans to Mars that China is planning to "sit this one out"?

Plus, China has currently only landed a 140 kg rover on our Moon using expendable rockets and spacecraft, so in order for them to scale up to something that is truly meaningful they will have to be dedicating $Billions more per year for decades to come. And other than "science", I'm not sure exactly what they will be doing on our Moon that will cause concern within our U.S. Government.

People tend to confuse space exploration with prestige, mainly because of the Apollo program. But Apollo was an effort to help win a political problem, which was the Cold War, and we lack such a motivator today here on Earth that can be solved by sending humans out into space.

Fast forward to today and NASA's primary skill set is in doing "science", both with robotic systems and in learning how humans can survive in space. But otherwise the U.S. Government does not have plans to use NASA to compete in some sort of "Space Race". Even this Deep Space Gateway (DSG) is kind of a muddled program that tries to get NASA closer to Mars while using the Congressionally-mandated SLS and Orion.

But as we see with the current Trump Administration proposed budget, Trump does not think we need MORE government-funded science, but LESS. So if the only goal for the DSG/DST are "science", then that is shaky ground to build a program on...
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 06/25/2017 08:15 pm
But as we see with the current Trump Administration proposed budget, Trump does not think we need MORE government-funded science, but LESS. So if the only goal for the DSG/DST are "science", then that is shaky ground to build a program on...

You are making a mountain out of a molehill.

Quote
Space science, which includes missions to study Earth, other planets in the solar system, astrophysics, solar physics and space weather, would receive $5.7 billion under the Trump administration’s budget request, about $53 million less than in the enacted FY ’17 budget.
https://spaceflightnow.com/2017/05/23/trumps-nasa-budget-request-reduces-earth-science-eliminates-education-office/

The Obama administrations FY 2017 budget request had a notional 2018 spending amount of 5408.5 million. So, this is almost $300 million more than Obama's notional out year funding profile submitted over a year ago.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: The Amazing Catstronaut on 06/25/2017 10:03 pm
China doesn't have a national impetus for exploration on this level, whilst for the US it's more of a cultural need. USA has unquestionable global media and economic reach, China will compete on those terms, not on slinging stuff into the solar system.  To think national competitiveness is the reason to go to space will just result in a pointless repeat in the moon landings. A federal government impelled equivalent of masturbatory competitive project with taxpayers dollars won't solve the underlying issue of space being as untouchable and distant as ever.

People need better reasons to act in space than just pandering to insecurity. Granted, science is not enough, but prestige should be a result, not the reason.

China would doubtless fill the void if America left that void unfilled, but it isn't unfilled yet.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 06/25/2017 10:48 pm
But as we see with the current Trump Administration proposed budget, Trump does not think we need MORE government-funded science, but LESS. So if the only goal for the DSG/DST are "science", then that is shaky ground to build a program on...

You are making a mountain out of a molehill.

Actually I'm just pointing out that no one should assume the molehill will to turn into a mountain...  ;)

Quote
Space science, which includes missions to study Earth, other planets in the solar system, astrophysics, solar physics and space weather, would receive $5.7 billion under the Trump administration’s budget request, about $53 million less than in the enacted FY ’17 budget.

I certainly didn't expect any big changes in this transition budget, from either Presidential candidates, so small movement up or down really doesn't tell us much today.

But in order for the DSG and DST to happen within the next decade there needs to be not only a commitment to the effort from Trump, but Congress has to increase NASA's budget substantially in order to get the program going.

That has to happen soon (i.e. FY2019) since the Deep Space Gateway is a major program, not only because it is supposed to be an international program (i.e. Secretary of State has to be involved) with multiple new human-rated hardware elements (reusing elements is good, but they are being used in new ways), but also because it requires the start of serial production for the SLS and Orion.

It will be interesting to see if V.P. Pence pushes for this in the soon-to-be-reconstituted National Space Council, which should be our first indication of whether the DSG/DST proposal will make it to reality.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 06/26/2017 01:34 am
The Obama administrations FY 2017 budget request had a notional 2018 spending amount of 5408.5 million. So, this is almost $300 million more than Obama's notional out year funding profile submitted over a year ago.

But less than the prior year's enacted.  It's an increase over a projection but a cut from last year's actual budget.

And a fraction of what something like DSG will need, which isn't in the Administration's FY18 request.

As happens with most transitions, FY18 a placeholder NASA budget for the current Administration -- they didn't have leadership in place on the 9th floor or in the White House (whether National Space Council or something else) when the FY18 request was formulated.  And they won't for some time to come.

Planetary science, DSG, SLS/Orion, etc. are all angels on a pin until some leadership with known positions are place (at least), and even then, we'll want to wait until they put out a budget request to see where they really come down.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 06/26/2017 11:10 pm

But in order for the DSG and DST to happen within the next decade there needs to be not only a commitment to the effort from Trump, but Congress has to increase NASA's budget substantially in order to get the program going.

That has to happen soon (i.e. FY2019) since the Deep Space Gateway is a major program, not only because it is supposed to be an international program (i.e. Secretary of State has to be involved) with multiple new human-rated hardware elements (reusing elements is good, but they are being used in new ways), but also because it requires the start of serial production for the SLS and Orion.

SLS and Orion already are producing as if it was serial production. They plan to start building serial number 3 hydrogen tank for instance. There is no reason to think their budget needs to increase for serial production. It could actually decrease. I believe that Orion/CEV funding peaked around 2009/2010 for instance. Obviously, serial production is expensive, but development is also expensive as well. Which is more so? My educated guess is that for 1 flight/year, it is development that is more expensive than serial production.

And there are other significant pieces of NASA's budget that are in transition period where it is not optimized and efficient. For instance, 3 providers are being paid for LEO crew rotation, but only 1 is currently delivering that service. So, I really think that DSG/DST doesn't require any actual increase to NASA's budget beyond annual inflation adjustment.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 06/27/2017 01:48 am
SLS and Orion already are producing as if it was serial production. They plan to start building serial number 3 hydrogen tank for instance.

There are clear lines that delineate between development and production. You can use production tooling, and you can build parts that may not be changing between development and production, but until program management, engineering, and the production folks sign off that a particular SLS configuration is ready for production, it's not yet in production.

Quote
There is no reason to think their budget needs to increase for serial production. It could actually decrease.

Absolutely. You normally don't need as many engineering resources for sustaining production as you do for development, so overhead changes like that are normal. Keep in mind though that SLS development is not ending anytime soon, since Block 1B and Block 2 are still in development for many years to come.

Quote
I believe that Orion/CEV funding peaked around 2009/2010 for instance.

When development spending peaked has no relationship to what a production version of the SLS or Orion will cost on a yearly basis. Plus, production costs are divided up between procurement costs and production & test costs, with procurement being committed years before production occurs.

Quote
Obviously, serial production is expensive, but development is also expensive as well. Which is more so? My educated guess is that for 1 flight/year, it is development that is more expensive than serial production.

My post was not about the difference in cost between development and production. And what has not been decided on yet is how the SLS and Orion material will be procured, which has a significant effect on the per/unit cost for both.

For instance in 2002 NASA announced a contract extension for the Shuttle SRM's, bringing the contract value up to $2.4B for 70 motors (35 flight sets) for use through 2007. That works out to $69M per set, but that was based on decades of serial production and building on average of 7 sets per year. Congress has not yet determined what the flight rate for the SLS will be, but chances are it will be between 1-1.5/year, so the per unit cost of a set of SRM's will not be anywhere near what the Shuttle SRM costs were due to the low production volume.

What NASA is waiting for from Congress is authorization to start full-up production, which will also define what the planned production rate will be. It could only be a year-to-year authorization, which is the most expensive way to buy & build, or it could be a multi-year authorization. But so far Congress has only authorized some - some - long lead material, like the RS-25 engines.

Quote
And there are other significant pieces of NASA's budget that are in transition period where it is not optimized and efficient. For instance, 3 providers are being paid for LEO crew rotation, but only 1 is currently delivering that service. So, I really think that DSG/DST doesn't require any actual increase to NASA's budget beyond annual inflation adjustment.

You are talking about the ISS program, which is not related to the DSG/DST program, and does not share (at this time) any transportation elements. So the DSG/DST program is going to be IN ADDITION TO the ISS program, and not a 1:1 replacement of it. At least for part of the life of both programs.

And again, I'm not talking cost per se, just pointing out that at this point the SLS and Orion programs are only authorized for development, and no authorization has been provided by Congress for serial production. No one outside of NASA, not even Congress, knows what the production costs will be (NASA has not shared them with Congress yet), so there will need to be some discussion within Congress about the total proposed costs for the DSG/DST proposed program (station costs, installation costs, support costs, etc.).

When will that happen? I think we'll have to wait for V.P. Pence to push that forward - if the Trump Administration wants to back this proposal...
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: redliox on 07/03/2017 12:25 am
Japan is apparently declaring it's intention to get to the Moon by 2030, in the process agreeing to assist with the DSG:
http://www.japantimes.co.jp/news/2017/07/01/national/science-health/jaxa-reveals-plans-put-japanese-moon-2030/#.WVkO3ojyjIW (http://www.japantimes.co.jp/news/2017/07/01/national/science-health/jaxa-reveals-plans-put-japanese-moon-2030/#.WVkO3ojyjIW)
http://www.astrowatch.net/2017/07/japan-plans-to-land-astronauts-on-moon.html (http://www.astrowatch.net/2017/07/japan-plans-to-land-astronauts-on-moon.html)
Quote
The Japan Aerospace Exploration Agency (JAXA) has ambitious plans to put an astronaut on the moon sometime around 2030, according to new proposals from the space agency.

This is the first time JAXA has publicly explored sending astronauts anywhere beyond the International Space Station, a JAXA spokeswoman said Friday.

The idea is to first join a NASA-led mission in 2025 to build a space station in the moon’s orbit — part of a longer-term effort by NASA to reach Mars.

Tokyo hopes that contributing to the multinational mission and sharing Japanese technology will land it a coveted spot at the station, from which it could eventually put an astronaut on the moon, the spokeswoman said.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 07/03/2017 02:31 am
They need a manned lunar lander
and probably a partner (ESA?) to help with R&D costs.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: calapine on 07/03/2017 12:43 pm
An ESA-JAXA co-operation would be a very nice start to a "Moon renaissance". 
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Khadgars on 07/03/2017 09:07 pm
An ESA-JAXA co-operation would be a very nice start to a "Moon renaissance".

I agree, except it all starts with NASA DSG including SLS/Orion which we all know how everyone on here feels about.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 07/04/2017 12:47 am
An ESA-JAXA co-operation would be a very nice start to a "Moon renaissance".

I agree, except it all starts with NASA DSG including SLS/Orion which we all know how everyone on here feels about.
Speak for yourself, I think DSG great idea. Back to moon would be better but endup being cancelled because high cost. DSG is achievable on current NASA budget. Once in place the next step from DSG to moon is not so big or expensive.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: yg1968 on 10/11/2017 03:50 am
A couple of notes on DSG:

Quote
Crusan: "for the first time ever, we have refueling baselined in our human space flight architecture."  Finally. Whoo hoo!!  #leag2017

https://twitter.com/george_sowers/status/917744545340764161

Quote
Jason Crusan asked how DSG is fueled. His answer: "I do not care where the fuel comes from" for Deep Space gateway. #LEAG2017

https://twitter.com/NASAWatch/status/917743640730132480
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: wannamoonbase on 10/13/2017 01:27 pm
A couple of notes on DSG:

Quote
Crusan: "for the first time ever, we have refueling baselined in our human space flight architecture."  Finally. Whoo hoo!!  #leag2017

https://twitter.com/george_sowers/status/917744545340764161

Quote
Jason Crusan asked how DSG is fueled. His answer: "I do not care where the fuel comes from" for Deep Space gateway. #LEAG2017

https://twitter.com/NASAWatch/status/917743640730132480

Sounds like a wide open door for commercial opportunities.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Proponent on 10/13/2017 01:48 pm
Once in place the next step from DSG to moon is not so big or expensive.

How do you figure that, especially if just keeping the DSG going is draining, say, $3 billion per year from the budget?  How does the DSG help get to the surface of the moon?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 10/13/2017 04:53 pm
Once in place the next step from DSG to moon is not so big or expensive.

How do you figure that, especially if just keeping the DSG going is draining, say, $3 billion per year from the budget?  How does the DSG help get to the surface of the moon?
The whole idea if DSG is avoid ISS huge support costs of $3B. Spares holding alone is a nightmare, as an example there are 140 different models of fans on ISS.

DSG is lot smaller and simpler than ISS, will be unmanned for 90% of time. Annual SLS/Orion launch is biggest cost and that may come out of separate budget.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Proponent on 10/13/2017 08:15 pm
The whole idea if DSG is avoid ISS huge support costs of $3B. Spares holding alone is a nightmare, as an example there are 140 different models of fans on ISS.

DSG is lot smaller and simpler than ISS, will be unmanned for 90% of time. Annual SLS/Orion launch is biggest cost and that may come out of separate budget.

But just sending one Orion/SLS a year to DSG probably costs about $3 billion.  What's the point of maintaining DSG if what you really want to do is go to the moon?

EDIT:  I do get your point about DSG being much smaller and presumably much cheaper to maintain than ISS.  The problem is that reaching DSG is far more expensive than reaching ISS.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Lars-J on 10/13/2017 08:38 pm
The whole idea if DSG is avoid ISS huge support costs of $3B. Spares holding alone is a nightmare, as an example there are 140 different models of fans on ISS.

DSG is lot smaller and simpler than ISS, will be unmanned for 90% of time. Annual SLS/Orion launch is biggest cost and that may come out of separate budget.

But just sending one Orion/SLS a year to DSG probably costs about $3 billion.  What's the point of maintaining DSG if what you really want to do is go to the moon?

EDIT:  I do get your point about DSG being much smaller and presumably much cheaper to maintain than ISS.  The problem is that reaching DSG is far more expensive than reaching ISS.

Right. The DSG only makes sense because that's how far Orion can go. SLS+Orion needs a destination, one that can be delivered by SLS+Orion. If Orion was capable of entering and leaving LLO, you'd be sure to hear proposals about a LLO gateway.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 10/13/2017 09:50 pm
But just sending one Orion/SLS a year to DSG probably costs about $3 billion.  What's the point of maintaining DSG if what you really want to do is go to the moon?

"If you want to take Vienna, take Vienna." -- Napoleon Bonaparte, circa 1805

"We want to go to the surface of the Moon." -- National Space Council, October 5, 2017

"Nah, we'll spend the next decade building another space station." -- NASA, 45 days later.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 10/13/2017 10:15 pm
The whole idea if DSG is avoid ISS huge support costs of $3B. Spares holding alone is a nightmare, as an example there are 140 different models of fans on ISS.

DSG is lot smaller and simpler than ISS, will be unmanned for 90% of time. Annual SLS/Orion launch is biggest cost and that may come out of separate budget.

But just sending one Orion/SLS a year to DSG probably costs about $3 billion.  What's the point of maintaining DSG if what you really want to do is go to the moon?

EDIT:  I do get your point about DSG being much smaller and presumably much cheaper to maintain than ISS.  The problem is that reaching DSG is far more expensive than reaching ISS.
 

Marginal cost for 1 flight is not even close to 3 billion. We have lots of data on the cost of the components making up the SLS. You can't bill 100% of the cost of maintaining SLS/Orion to the gateway in a scenario where they are being used for lunar landings as well. And extrapolating operation costs from development costs is just as silly. Besides, with the gateway, it is one SLS/Orion flight per lunar landing. Without the gateway, it is 1 SLS/Orion flight per lunar landing. The gateway adds zero additional expense for supporting a ground campaign except a few 100 m/s of total trip delta-v. It certainly doesnt add billions in fixed yearly operational costs.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 10/14/2017 01:08 am
Marginal cost for 1 flight is not even close to 3 billion.

Marginal cost arguments are like coupons or store sales.  To "save", you actually have to spend more.

SLS/Orion/Ground Systems are consuming 85% of the exploration budget.

Without an early ISS retirement or a multi-billion dollar increase to the NASA topline, there is little to no budget to buy additional launches on the margin. 

Absent a big budget bump, the program needs an absolute reduction in its transportation costs so it can afford a reasonable number of payloads and missions and a safe launch rate.

Quote
And extrapolating operation costs from development costs is just as silly.

There is a relationship, though.  Launch systems with high development costs tend to have high operations costs.  Launch systems with low development costs tend to have low operations costs.

In the specific case of NASA-developed launch systems, annual operations costs tend to match annual development costs.  This is not surprising given the fixed civil and contractor workforce and infrastructure.

STS development ramped up to $4B+/yr. (in 2010 dollars) by 1976 and the STS budget never fell significantly under that level until the program's end.  Operations grew to consume the budget left by development ramping down.  In fact, STS operations were in the $6-7B/yr. range from 1982-1992.

Similarly, SLS/Orion/Ground Systems was $3.6B in 2016 and is projected to be $3.8B in 2022, when EM-2 flies and SLS/Orion achieves a certain level of operability.

Given STS history and what we're seeing in the budget around 2022, it's not unreasonable to assume that SLS/Orion/Ground Systems will approach $4B/yr. for the foreseeable future.

Quote
You can't bill 100% of the cost of maintaining SLS/Orion to the gateway in a scenario where they are being used for lunar landings as well.

Whether it's to the DSG or to the lunar surface, at a rate of one mission per year, we're looking at a cost approaching $4B per mission before DSG or lunar lander costs are included.  Or before center costs, S&MA, IT, CoF, etc. are included.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: savuporo on 10/15/2017 02:32 am
Bob Zubrin is totally not on board. I'm shocked

https://www.youtube.com/watch?v=EK8Zhgy5qXQ
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Steven Pietrobon on 10/15/2017 06:46 am
That was a really great panel. A lot better than some of the panels at the IAC!
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Proponent on 10/15/2017 05:46 pm
Bob Zubrin is totally not on board. I'm shocked <video link elided -- Proponent>

Thanks much -- that was actually quite interesting.  Zubrin tears into DSG, pointing out, among other things, that never before in the history of planning for missions to Mars (or the moon), dating back to von Braun, has anyone said that a cis-lunar station is desirable.  He also points out that justifying the DSG as a base for tele-operation of lunar rovers is hard to justify when there are now self-driving vehicles capable of coping with Los Angeles traffic.

A NASA Ames employee, speaking on her own and not representing NASA's views, says clearly that NASA should buy transportation to Mars from SpaceX (I thinks that's wrong: it should request bids from industry).  She also says that characterizing any current martian life is a prerequisite to sending humans.

The most interesting thing is how the panel came about.  It was originally to have been a debate on the proposition "The Deep Space Gateway has merit" -- but Zubrin couldn't find anyone willing to argue the affirmative!  However, as soon as Zubrin said this, someone In the audience volunteered to advocate for DSG!

I did not find him particularly convincing except in so far as he argued that DSG is a testing ground for the Lockheed Martin hab module for a Mars mission.  I think that could be a valid point if a decision had been made to develop (and fund!) Lockheed Martin's Mars architecture.

But no defense of DSG as a way to the lunar surface is offered.  And note that the topic of this thread is about DSG as a step toward Mars, not the moon.

At this point, I have fairly firmly convinced that DSG is a bad idea.  Therefore, it is quite possible that I am missing or under-weighting pro-DSG arguments.  I encourage DSG's supporters to watch the video to see whether they can find support for DSG that I have overlooked.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 10/15/2017 06:19 pm
DSG is more about doing something affordable in BLEO in near term that can be used for Mars missions. A dedicated Mars mission that goes direct maybe cheaper overall but it would mean not doing anything meaningful in BLEO until 2030s. Moon was not on NASA authorized todo list till a month ago, so DSG was next best thing. Whether lunar architecture that uses SLS needs DSG it is another debate.

Sent from my SM-T810 using Tapatalk

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: savuporo on 10/15/2017 06:26 pm
The most interesting thing is how the panel came about.  It was originally to have been a debate on the proposition "The Deep Space Gateway has merit" -- but Zubrin couldn't find anyone willing to argue the affirmative!

at a Mars Society convention, thats hardly surprising.

Quote
However, as soon as Zubrin said this, someone In the audience volunteered to advocate for DSG!
I did not find him particularly convincing except in so far as he argued that DSG is a testing ground for the Lockheed Martin hab module for a Mars mission. 
LOL, you didn't pick up that he only came up there to put up intentionally preposterous opposition ? He says as much directly to Zubrin in last couple of seconds
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 10/15/2017 09:12 pm

Absent a big budget bump, the program needs an absolute reduction in its transportation costs so it can afford a reasonable number of payloads and missions and a safe launch rate.

Current NASA funded HSF development programs: SLS Block 1, SLS Block 1B, Orion, Deep Space Habitats(NextSteps partnership), EM-1 co-manifested payloads, Starliner, Dragon V2, Dream Chaser cargo. That is 8 significant individual initiatives. Obviously, the pipeline needs to be emptied somewhat before piling on more development programs.

Quote
Similarly, SLS/Orion/Ground Systems was $3.6B in 2016 and is projected to be $3.8B in 2022, when EM-2 flies and SLS/Orion achieves a certain level of operability.

Are those numbers inflation adjusted? If they are not, $3.8B in 2022 is less than $3.6B in 2016.

Quote
STS development ramped up to $4B+/yr. (in 2010 dollars) by 1976 and the STS budget never fell significantly under that level until the program's end.  Operations grew to consume the budget left by development ramping down.  In fact, STS operations were in the $6-7B/yr. range from 1982-1992.

STS tended to do 5-8 missions per year which equates to 10-16 SRBs(refurbishment costs were roughly equivalent to making new ones) or 40-64 segments(4-6 SLS missions) and expendable hydrolox tankage equivalent to ~3500 mT-~5600 mT. That is tankage equivalent to ~3-5 SLS missions. STS didn't expend any engines, but at $38 million per RL-10 and $58 million per RS-25, we are talking in the neighborhood of $700 million per year for 2 missions(Block 1B with EUS). STS was operating twice as many pads, twice as many crawlers. And actual peak Shuttle development costs were around $6 billion.

(http://1.bp.blogspot.com/-2B07XovjILo/TZzYTjCrCfI/AAAAAAAAA4I/MiNGjDelcqg/s1600/piebye.11.jpg)

There doesn't seem to be much correlation between launch rate and cost. For instance, between 1980 and 1985, costs fell from 7 billion to 6 billion, but launch rate rose from 1 to 9. Also, from 1990 to 1995 fell from $7 billion to $4 billion, but launch rate remained steady at ~7-8 per year. The major factor for SLS/Orion costs are no SLS/Orion or SLS/Orion. 1/2/3 launches per year is a relatively minor factor. Thusly, DSG logistical support is essentially also a minor factor. Crew can be rotated with excess Orion capacity. It can be deployed and supplied with excess SLS capacity.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 10/15/2017 10:17 pm
Current NASA funded HSF development programs:

- SLS Block 1, SLS Block 1B = Development only, with only long-lead procurement for engines
- Orion = Development only, and it is unknown who will build operational Service Modules
Both the SLS and the Orion are only transportation elements, not actual exploration systems.

- Deep Space Habitats(NextSteps partnership) = Not yet a fully-funded program, just prototypes
- EM-1 co-manifested payloads = how is this significant? Every rocket can have co-manifested payloads.

- Starliner, Dragon V2, Dream Chaser cargo = Part of the "Space Operations" budget, not "Exploration"

Quote
That is 8 significant individual initiatives. Obviously, the pipeline needs to be emptied somewhat before piling on more development programs.

Cherry-picking programs and trying to imply that there are too many or not enough is specious. I doubt you would say the same if there were 8 fully-funded programs that were specifically using the SLS and Orion.

Quote
...That is tankage equivalent to ~3-5 SLS missions. STS didn't expend any engines, but at $38 million per RL-10 and $58 million per RS-25, we are talking in the neighborhood of $700 million per year for 2 missions(Block 1B with EUS).

You are using incomplete and inaccurate information to estimate SLS costs. For instance, the Shuttle costs were dependent on a much higher flight rate than the SLS is projected to fly at, which means the costs for an SRM would be less for the Shuttle - plus the SLS SRM has extra segments, so a set of them is more costly anyways.

Quote
There doesn't seem to be much correlation between launch rate and cost.

For a very good reason - a Shuttle launch was the result of spending most of the allocated money BEFORE the launch, regardless when it eventually launched. Also, money has to be committed years in advance for long-lead items like Solid Rocket Motors (SRM) and the External Tank (ET).

For instance, in 2002 NASA extended a contract for SRM's (http://www.spaceref.com/news/viewpr.html?pid=8785) that was originally awarded in 1998, and the extension was going to cover SRM's delivered thru May 2007.

For United Space Alliance, they were paid about $99M per month regardless the flight rate (https://www.thefreelibrary.com/United+Space+Alliance+and+NASA+Sign+Space+Flight+Operations+Contract-a018721721), so when delays occurred they still were paid (like during the Columbia stand down)

Quote
The major factor for SLS/Orion costs are no SLS/Orion or SLS/Orion.

What the heck does that mean?

Quote
1/2/3 launches per year is a relatively minor factor.

Have you ever looked at how big the SLS is supposed to be? That kind of assembly is not cheap, and don't think it's a minor upgrade just because people say "it's Shuttle derived". Speaking from a manufacturing perspective, that sucker costs a lot of money to build.

Quote
Thusly, DSG logistical support is essentially also a minor factor. Crew can be rotated with excess Orion capacity. It can be deployed and supplied with excess SLS capacity.

Those statements make no sense either, especially because it literally takes an act of Congress to build and launch an SLS and Orion, so there is no such thing as "excess capacity" for either one of them. Even the Shuttle planned for launches years in advance, and so will missions that require the unique services of the SLS and Orion.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 10/16/2017 12:09 am
Deep Space Habitats(NextSteps partnership), EM-1 co-manifested payloads

These are low single to tens of millions of dollars.  They're not even a rounding error in the Exploration Budget.

Quote
Starliner, Dragon V2, Dream Chaser cargo.

The development budget for these is coming down quickly, from $1.2B in 2016 to $36M (million) in 2020.  The outyear savings have already been allocated to ISS and Exploration Research.

This is what should be happening in the Exploration budget.  But instead...

Quote
Current NASA funded HSF development programs: SLS Block 1, SLS Block 1B, Orion,

These are not coming down.  Instead the SLS/Orion budget is approaching $4B even in 2022, the same year Orion completes EM-2, SLS Block 1B flies, and both achieve some measure of operability. 

Again, absent early ISS retirement or a multi-billion boost to the NASA topline, there is no pot of money to free up to funds for new exploration developments.  Expect consequent delays in DSG (or any other exploration hardware) until ISS retirement, over and above the emerging delays on EM-1.

Quote
There doesn't seem to be much correlation between launch rate and cost.

Which is the point.

Marginal cost arguments and savings projections have no relevance in programs like STS and SLS/Orion, which cost $4B or more per year regardless of flight rate and whether they're in development or operations.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Khadgars on 10/16/2017 03:12 pm
@Coastal Ron  Did we not already establish your manufacturing experience does not apply to these Aerospace programs?  Please stop stating your opinion as undeniable facts.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Proponent on 10/16/2017 07:10 pm
The most interesting thing is how the panel came about.  It was originally to have been a debate on the proposition "The Deep Space Gateway has merit" -- but Zubrin couldn't find anyone willing to argue the affirmative!

at a Mars Society convention, thats hardly surprising.

At the conference itself, it would not be surprising.  But the agenda was prepared months in advance.  As Zubrin says, at a previous conference, the Mars Society did attract someone from NASA to argue in favor of ARRM.

Quote
LOL, you didn't pick up that he only came up there to put up intentionally preposterous opposition ? He says as much directly to Zubrin in last couple of seconds

I've just watched again from 37:30 to 42:30, but I'm not hearing such a statement.  Could you please be more specific as to the time or provide the direct quote?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 10/17/2017 03:08 am
Bob Zubrin is totally not on board. I'm shocked <video link elided -- Proponent>

Thanks much -- that was actually quite interesting.  Zubrin tears into DSG, pointing out, among other things, that never before in the history of planning for missions to Mars (or the moon), dating back to von Braun, has anyone said that a cis-lunar station is desirable.  He also points out that justifying the DSG as a base for tele-operation of lunar rovers is hard to justify when there are now self-driving vehicles capable of coping with Los Angeles traffic.

A NASA Ames employee, speaking on her own and not representing NASA's views, says clearly that NASA should buy transportation to Mars from SpaceX (I thinks that's wrong: it should request bids from industry).  She also says that characterizing any current martian life is a prerequisite to sending humans.

The most interesting thing is how the panel came about.  It was originally to have been a debate on the proposition "The Deep Space Gateway has merit" -- but Zubrin couldn't find anyone willing to argue the affirmative!  However, as soon as Zubrin said this, someone In the audience volunteered to advocate for DSG!

I did not find him particularly convincing except in so far as he argued that DSG is a testing ground for the Lockheed Martin hab module for a Mars mission.  I think that could be a valid point if a decision had been made to develop (and fund!) Lockheed Martin's Mars architecture.

But no defense of DSG as a way to the lunar surface is offered.  And note that the topic of this thread is about DSG as a step toward Mars, not the moon.

At this point, I have fairly firmly convinced that DSG is a bad idea.  Therefore, it is quite possible that I am missing or under-weighting pro-DSG arguments.  I encourage DSG's supporters to watch the video to see whether they can find support for DSG that I have overlooked.



The DSG could be used to build the lunar base. For example the SLS would throw 40 tonne habitats to the DSG. The station's reusable lander would take the habitats down to the lunar surface. Same for heavy cargoes going to Mars.

Building the DSG 10 tonnes at a time is just using Orion on SLS as a Shuttle building the ISS. With a heavy lift launch vehicle lift most of the spacestation in a single launch, like SKYLAB. Enhancements like refuelling facilities may need additional launches.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 10/17/2017 03:26 am
Did we not already establish your manufacturing experience does not apply to these Aerospace programs?

No one told me. What cabal determined that?   :o

Quote
Please stop stating your opinion as undeniable facts.

Are you stating that as an undeniable fact or opinion?   :)

Look, we all participate in a public discussion, and if you don't like what my facts and opinions are then you are free to ignore or disagree with them. And as I'm sure you can tell from my Posts/Liked ratio, some people actually like what I write...  ;)

Let's get back to the topic at hand, shall we?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 10/17/2017 06:02 pm
Deep Space Habitats(NextSteps partnership), EM-1 co-manifested payloads

These are low single to tens of millions of dollars.  They're not even a rounding error in the Exploration Budget.

13 payloads at ~16 million a piece is hundreds of millions(can't find projected cost data for all missions). But stuff like the asteroid fly-by or lunar orbiters aren't cheap despite the size. And the habitat stuff was directed to be 50-100 million/year depending on the year.

Quote
Again, absent early ISS retirement or a multi-billion boost to the NASA topline, there is no pot of money to free up to funds for new exploration developments.  Expect consequent delays in DSG (or any other exploration hardware) until ISS retirement, over and above the emerging delays on EM-1.

If this was the case, the administration couldn't propose a 2018 cut of $550 million USD without cancelling any major programs. That is ballpark what a lunar lander would cost (per year) to develop. The fact is, without funding new developments as older ones get completed, the result is almost invariably a smaller NASA budget.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: whitelancer64 on 10/17/2017 06:06 pm
@Coastal Ron  Did we not already establish your manufacturing experience does not apply to these Aerospace programs?  Please stop stating your opinion as undeniable facts.

Manufacturing is an enormous part of aerospace programs. I am baffled why you think it would be irrelevant.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Lars-J on 10/17/2017 07:06 pm
@Coastal Ron  Did we not already establish your manufacturing experience does not apply to these Aerospace programs?  Please stop stating your opinion as undeniable facts.

Manufacturing is an enormous part of aerospace programs. I am baffled why you think it would be irrelevant.

I don't think that was his point. Read again.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 10/17/2017 08:40 pm
13 payloads

No.

Only five are partially or fully funded through HEOMD.

Quote
If this was the case, the administration couldn't propose a 2018 cut of $550 million USD

No.

The Administration's proposed cut to NASA's 2018 topline was based on program terminations and content reduction, not old development programs ending. 

For 2018, the White House proposed eliminating NASA's entire education program, terminating several earth science missions in development, and turning off earth science instruments on other operational missions.

Quote
The fact is, without funding new developments as older ones get completed, the result is almost invariably a smaller NASA budget.

Of course. 

But within the exploration budget, SLS/Orion are approaching $4B/yr. even after operations begin.  And they comprise 85% of the exploration budget.  So as long as SLS/Orion are around, there's little available funding within the exploration budget to do much actual exploration beyond Apollo 8-type jaunts.

Within the larger HEOMD budget, the savings from Commercial Crew development ending are already spoken for.  That leaves a future ISS ramp-down, which won't generate savings until 2024-2028 or later.

Within the larger NASA budget, we can suggest major cuts to another NASA directorate or program area (science, space technology, aeronautics, education after Congress restores it).  But that invites a political bloodbath that would expose SLS/Orion to termination.

The only other option is a multi-billion dollar budget increase to NASA's topline to pay for the National Space Council's lunar initiative.  But NASA is assuming existing constraints for that exercise.  Even if the White House requested such an increase, it's not in the Congressional cards in this political environment.

It looks like EM-1 will slip to sometime in the first half of 2020.  That puts EM-2 out in early 2023.  That might align DSG's ramp-up with an early ISS ramp-down circa 2024, but I would not bet on an early ISS retirement. 

Moreover, after the National Space Council asked NASA to get boots on the Moon, it's hard to see the White House putting weight behind a timeline that will only deploy DSG's first element shortly before the end of the Administration's last term in office (assuming this Administration lasts two terms).

Reading the tea leaves:

If the Administration doesn't care, I think DSG development and deployment muddles slowly into the early 2030s on very constrained funding.

If the Administration sorta cares, I think DSG is terminated and what little exploration funding is not consumed by SLS/Orion is poured into a COTS-ish lunar lander effort that aims for the kind of competition and efficient use of resources that SLS/Orion could have been.  Whether the primes let that effort live, turn it into another costly CCDev-type effort, or kill it in the crib is a roll of the dice at this point.

If the Administration really cares, I think a major redirection of SLS/Orion/DSG funding is proposed, which is summarily rejected by parochial interests in Congress, at which point the Administration doesn't care anymore, as happened with the two Administrations before them.

Quote
$550 million USD... That is ballpark what a lunar lander would cost (per year) to develop.

????

Any dollar amount is enough develop any undefined lunar lander over any undefined period of time.

And flat-funding is a development nightmare.  Development budgets should resemble Bell curves.

Such Bell curve-shaped development budgets could be created for exploration hardware and payloads within the $4B+ exploration budget.  But only if SLS/Orion costs stop approaching $4B in the outyears.

Based on STS experience and the SLS/Orion/Ground Systems budget through 2022 (current EM-2/Orion crew-operational/SLS Block 1B operational), that's not in the cards.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Lar on 10/17/2017 09:06 pm
Play the ball not the man, please. Casting aspersions on each other's experience and relevance is only sort of helpful at best.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 10/17/2017 09:43 pm
Play the ball not the man, please. Casting aspersions on each other's experience and relevance is only sort of helpful at best.
Agreed - while some of us here argue details on such things; meanwhile on every single post or picture about Space activities on social media and other websites, trolls and flat earthers are working harder than coal miners to spread the meme that space travel both manned and unmanned isn't even real. Argument energies should be going into fighting them with every spare bit of energy you have.

Then again; maybe life is too short for that... :(
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Patchouli on 10/18/2017 02:18 am
]

The DSG could be used to build the lunar base. For example the SLS would throw 40 tonne habitats to the DSG. The station's reusable lander would take the habitats down to the lunar surface. Same for heavy cargoes going to Mars.

Building the DSG 10 tonnes at a time is just using Orion on SLS as a Shuttle building the ISS. With a heavy lift launch vehicle lift most of the spacestation in a single launch, like SKYLAB. Enhancements like refuelling facilities may need additional launches.

Agreed it would be better the assemble DSG from Skylab sized sections since SLS can lift them.

I think it would be best to assemble DSG in LEO then attach an ion tug or a mostly full EUS to it and take it to lunar vicinity.

LEO rendezvous and assembly is old hat.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 10/18/2017 11:57 am
]

The DSG could be used to build the lunar base. For example the SLS would throw 40 tonne habitats to the DSG. The station's reusable lander would take the habitats down to the lunar surface. Same for heavy cargoes going to Mars.

Building the DSG 10 tonnes at a time is just using Orion on SLS as a Shuttle building the ISS. With a heavy lift launch vehicle lift most of the spacestation in a single launch, like SKYLAB. Enhancements like refuelling facilities may need additional launches.

Agreed it would be better the assemble DSG from Skylab sized sections since SLS can lift them.

I think it would be best to assemble DSG in LEO then attach an ion tug or a mostly full EUS to it and take it to lunar vicinity.

LEO rendezvous and assembly is old hat.


The block 1 SLS can lift 70 tonnes to LEO, later versions 105 tonnes. IMHO That is a reasonable size for a mini spacestation.

The first module of the DSG is the Power and Propulsion Element (PPE). With a few minor changes, like the guidance system, that is a space tug in its own right.

Whether a 50kW SEP (Solar Electric Propulsion) is sufficient to push 105 tonnes out of LEO I do not know. The SEP will probably have been sized for station keeping in lunar orbit.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: envy887 on 10/18/2017 05:20 pm
]

The DSG could be used to build the lunar base. For example the SLS would throw 40 tonne habitats to the DSG. The station's reusable lander would take the habitats down to the lunar surface. Same for heavy cargoes going to Mars.

Building the DSG 10 tonnes at a time is just using Orion on SLS as a Shuttle building the ISS. With a heavy lift launch vehicle lift most of the spacestation in a single launch, like SKYLAB. Enhancements like refuelling facilities may need additional launches.

Agreed it would be better the assemble DSG from Skylab sized sections since SLS can lift them.

I think it would be best to assemble DSG in LEO then attach an ion tug or a mostly full EUS to it and take it to lunar vicinity.

LEO rendezvous and assembly is old hat.


The block 1 SLS can lift 70 tonnes to LEO, later versions 105 tonnes. IMHO That is a reasonable size for a mini spacestation.

The first module of the DSG is the Power and Propulsion Element (PPE). With a few minor changes, like the guidance system, that is a space tug in its own right.

Whether a 50kW SEP (Solar Electric Propulsion) is sufficient to push 105 tonnes out of LEO I do not know. The SEP will probably have been sized for station keeping in lunar orbit.

By my calcs (2.5 N per 50 kW, 8.0 km/s dv required) it would take a 50 kW thruster 10 years to move 100 tonnes from LEO to LLO.

But with a much larger 1.5 MW array and 75 N worth of state-of-the-art ion thrusters it could be done in about 4 months.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 10/18/2017 10:43 pm
How much damage to the arrays would happen if they lingered too long in the Van Allen belts; even with an optimized trajectory minimizing exposure? Assuming a slow SLS launch rate; what about an SEP bus that could move it to LLO in a bit less than a year?

I'm impressed and a little excited by the prospects of SEP. The best thrusters available and the largest gallium-arsenide arrays possible should be able to shift a lot of stuff around efficiently. A chemical (hypergolic or LOX/CH4)/SEP combo would bring a lot of capability to bear. A 500kw array would be how large compared to the ISS 'acreage' of panels?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: savuporo on 10/19/2017 12:18 am
A 500kw array would be how large compared to the ISS 'acreage' of panels?

https://trs.jpl.nasa.gov/bitstream/handle/2014/45034/11-2964_A1b.pdf

That's for 300kw

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Patchouli on 10/19/2017 12:31 am


By my calcs (2.5 N per 50 kW, 8.0 km/s dv required) it would take a 50 kW thruster 10 years to move 100 tonnes from LEO to LLO.

But with a much larger 1.5 MW array and 75 N worth of state-of-the-art ion thrusters it could be done in about 4 months.

50 KW would be much too small for SLS sized payloads.

But the parking orbit need not be at ISS altitudes it can be higher or even elliptical so you may not need 1.5 MW either.
Since SLS Block IB can throw the 37,300Kg Skylab II into a lunar trajectory and just a simple tug maybe even one with chemical engines would be enough to place it where's it's needed I feel that concept is probably be the right one to go with.
If the EUS had IVF added to it a large SEP tug may not be needed at all even for Skylab II as the EUS could take it through TLI and place it in a high lunar orbit.
Just use the SEP engines to lower it down to LLO.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: MATTBLAK on 10/19/2017 12:38 am
Helpful examples above, thanks. So a 500kw solar array using modern methods and technology would not be out of the question and still probably be smaller than the ISS size-spread.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Steven Pietrobon on 10/19/2017 06:16 am
The block 1 SLS can lift 70 tonnes to LEO, later versions 105 tonnes. IMHO That is a reasonable size for a mini spacestation.

The 105 t is the IMLEO, including the EUS. The payload mass is about 93 t.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: A_M_Swallow on 10/19/2017 06:35 am
The block 1 SLS can lift 70 tonnes to LEO, later versions 105 tonnes. IMHO That is a reasonable size for a mini spacestation.

The 105 t is the IMLEO, including the EUS. The payload mass is about 93 t.

93 t - we will have to put the spacestation on a diet.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Proponent on 10/19/2017 12:31 pm
The DSG could be used to build the lunar base. For example the SLS would throw 40 tonne habitats to the DSG. The station's reusable lander would take the habitats down to the lunar surface. Same for heavy cargoes going to Mars.

NASA has no plans to build a moon base and is unlikely to have funding for such in foreseeable decades.  While a base could conceivably be staged through a station in high lunar orbit, I challenge you to find a single proposal for a moon base, from the many decades' worth of such proposals, that involves such a station.  If nobody from Goddard (and he proposed mining lunar water!) on thought it a good idea, why is it a good idea now?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 10/19/2017 05:33 pm
13 payloads

No.

Only five are partially or fully funded through HEOMD.

Whether it comes out of JAXA's budget or HEOMD, effect on overall NASA led exploration may be the same/similar.

The Administration's proposed cut to NASA's 2018 topline was based on program terminations and content reduction, not old development programs ending. 

The NASA 2017 budget request put cargo and crew transportation to the ISS(including development of domestic crew vehicles) at 2.758 billion. This component was fully funded, was it not? The NASA 2018 budget request put Cargo and Crew transportation to the ISS at 2.415 billion(a drop of 343 million without accounting for inflation). If this drop hadn't occurred, and education wasn't taken out, there would be basically no drop in NASA budget keeping all other funding the same(and not accounting for inflation). This drop is most attributable to the projected end of development in the 2018 time frame of major development programs. The specific funding for commercial crew development drops ~$500 million. This likely also reflects reductions in payments to Russia for missions in 2019+(that won't occur) because of end of development of domestic alternatives.

For 2018, the White House proposed eliminating NASA's entire education program, terminating several earth science missions in development, and turning off earth science instruments on other operational missions.

Even if you don't count the end of the education program, we are still talking about a pretty large drop, especially when you account for inflation. U.S. Inflation in 2017 was about 2.2%, which means the 2017 budget of 19.653 billion would be equivalent to the 19.993 billion(assuming 2018 inflation is equal to 2017 inflation). Adding education back in yields a budget for 2018 of 19.155 billion, a fall of $838 million which can be attributable to the completion(cancellations count) of several development programs. Again, without major new development program(s) to replace ones that are ending, the budget falls substantially. This could be the Europa lander, lunar lander, DSG or something else. It seems that there is a trade between bumping Planetary Science to account for new development programs and bumping Exploration spending to account for new development programs in order to maintain NASA's current funding levels. Your multi-billion dollar required increase to NASA's topline budget to fund any additional exploration equipment is simply incorrect especially considering the most expensive components of a lunar surface program are already funded (based on actual data from Apollo..this isn't theoretical). If a major billion dollar exploration program was created in FY 2018 roughly equivalent in size to the Orion crew vehicle, the result wouldn't have been a multi-billion dollar increase in NASA's top line budget. The result would have been an essentially flat budget(give or take 1%).
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 10/19/2017 08:26 pm
Whether it comes out of JAXA's budget or HEOMD, effect on overall NASA led exploration may be the same/similar.

No.

If an entity outside HEOMD is paying for an activity -- especially a foreign space agency -- then HEOMD will see no funding freed up when that activity ramps down or ends.

Quote
Even if you don't count the end of the education program, we are still talking about a pretty large drop, especially when you account for inflation. U.S. Inflation in 2017 was about 2.2%, which means the 2017 budget of 19.653 billion would be equivalent to the 19.993 billion

Unfortunately, this is unrealistic for planning purposes.

NASA's budget has not kept pace with inflation for decades.

Quote
The NASA 2017 budget request put cargo and crew transportation

May all be accurate.  I'm just pointing out there were terminations and content reductions, not just programs ramping down.

If it's accurate, there's a lesson here that HEOMD or NASA can't expect to keep every dollar freed up in future-year budgets from old developments ramping down or old programs ending.

For planning purposes, we shouldn't bet on retaining every dollar in the current budget and on inflation on top of that.

Either the older, more routine elements of the space exploration enterprise become more efficient with time or there will be less and less funding for new elements that actually do the exploring.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 10/19/2017 09:12 pm
Even if you don't count the end of the education program, we are still talking about a pretty large drop, especially when you account for inflation. U.S. Inflation in 2017 was about 2.2%, which means the 2017 budget of 19.653 billion would be equivalent to the 19.993 billion

Unfortunately, this is unrealistic for planning purposes.

NASA's budget has not kept pace with inflation for decades.

Plugging NASA's 2000 funding amount into a government CPI calculator yields a different conclusion:

https://data.bls.gov/cgi-bin/cpicalc.pl?cost1=13428&year1=200001&year2=201701

NASA budget from beginning of the century to 2017 was inflation adjusted and then some. I used CPI for my inflation calculations above.

edit:
It is also good to keep Apollo costs in mind in these discussions:

ranked by expense:

Saturn V: 6.4 B
CSM: 3.7 B
LEM: 2.2 B
Skylab: 2.2 B
LRV: .038 B

You could almost fund the LEM, Skylab and the LRV for the cost of the CSM. Likewise, you could possibly get away with funding the DSG, a lander and a rover for what is spent on Orion( $1.2 B/year). For reference, this would be a 2018 budget of 2017 enacted + inflation + $400 million. Not several billion dollars.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Proponent on 10/20/2017 01:44 am
Even if you don't count the end of the education program, we are still talking about a pretty large drop, especially when you account for inflation. U.S. Inflation in 2017 was about 2.2%, which means the 2017 budget of 19.653 billion would be equivalent to the 19.993 billion

Unfortunately, this is unrealistic for planning purposes.

NASA's budget has not kept pace with inflation for decades.

Plugging NASA's 2000 funding amount into a government CPI calculator yields a different conclusion:

https://data.bls.gov/cgi-bin/cpicalc.pl?cost1=13428&year1=200001&year2=201701

NASA budget from beginning of the century to 2017 was inflation adjusted and then some. I used CPI for my inflation calculations above.

edit:
It is also good to keep Apollo costs in mind in these discussions:

ranked by expense:

Saturn V: 6.4 B
CSM: 3.7 B
LEM: 2.2 B
Skylab: 2.2 B
LRV: .038 B

You could almost fund the LEM, Skylab and the LRV for the cost of the CSM. Likewise, you could possibly get away with funding the DSG, a lander and a rover for what is spent on Orion( $1.2 B/year). For reference, this would be a 2018 budget of 2017 enacted + inflation + $400 million. Not several billion dollars.

The CPI is not a good measure of inflation for NASA (https://forum.nasaspaceflight.com/index.php?topic=33022.msg1107882#msg1107882) programs, unless, perhaps, you want to compare the amounts of consumption that Americans sacrificed for NASA programs at different time.  The difference between the CPI and a more relevant inflation index, such as the NASA New-Start Index (NNSII) , has decreased in recent years, but NASA programs from the 1960's turn out to be far more expensive in today's dollars with the NNSII (https://forum.nasaspaceflight.com/index.php?topic=26522.msg861293#msg861293).
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: yg1968 on 10/26/2017 03:04 pm
SNC's version of the DSG (from the Von Braun symposium):

https://livestream.com/accounts/563450/events/7779847/videos/164953067

https://livestream.com/accounts/563450/events/7779847

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 10/26/2017 10:04 pm
NASA budget from beginning of the century to 2017 was inflation adjusted and then some.

No.

Based on a CPI website, NASA's FY 2017 budget gets NASA back to its FY 2000 budget, plus inflation. 

But that's the wrong inflator for NASA or the aerospace sector overall; FY 2000 is a low point in NASA's annual budget; and most importantly, there was no steady inflationary increase year-on-year during this time period.  The area under the curve that matters much more than the endpoints.

Even with a cherry-picked inflator and starting point, NASA's buying power in the intervening years did not keep pace with inflation.  In fact, in some of these years, NASA's budget actually shrank, even in constant dollars (forget inflation). 

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: ncb1397 on 10/27/2017 06:07 pm
NASA budget from beginning of the century to 2017 was inflation adjusted and then some.

No.

Based on a CPI website, NASA's FY 2017 budget gets NASA back to its FY 2000 budget, plus inflation. 

But that's the wrong inflator for NASA or the aerospace sector overall; FY 2000 is a low point in NASA's annual budget; and most importantly, there was no steady inflationary increase year-on-year during this time period.  The area under the curve that matters much more than the endpoints.

Even with a cherry-picked inflator and starting point, NASA's buying power in the intervening years did not keep pace with inflation.  In fact, in some of these years, NASA's budget actually shrank, even in constant dollars (forget inflation).

I think we are in agreement then. I don't really count a inflation adjustment as a budget increase, because it just counteracts the fall in the value of the dollar. But yes, they need some sort of yearly increase(in nominal terms) in order to fund additional exploration elements ultimately totaling several billion dollars on an annual basis. I mean, going back to the 1966 budget of ~6 billion USD just isn't feasible. Obviously, NASA is screwed without a "cost of living" adjustment. But they are getting, on average, yearly increases given the 1966 budget of 6 billion and the 2017 budget of ~19-20 billion. Goes without saying that it didn't keep up with inflation, especially between those two end points. But more recently, on a long term basis, it has more or less kept up with CPI after the recovery from Shuttle/Constellation/ISS construction ending in the same timeframe
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Coastal Ron on 10/27/2017 06:32 pm
Even with a cherry-picked inflator and starting point, NASA's buying power in the intervening years did not keep pace with inflation.  In fact, in some of these years, NASA's budget actually shrank, even in constant dollars (forget inflation).

I think we are in agreement then. I don't really count a inflation adjustment as a budget increase, because it just counteracts the fall in the value of the dollar. But yes, they need some sort of yearly increase(in nominal terms) in order to fund additional exploration elements ultimately totaling several billion dollars on an annual basis. I mean, going back to the 1966 budget of ~6 billion USD just isn't feasible. Obviously, NASA is screwed without a "cost of living" adjustment. But they are getting, on average, yearly increases given the 1966 budget of 6 billion and the 2017 budget of ~19-20 billion. Goes without saying that it didn't keep up with inflation, especially between those two end points.

I found the following on the "Budget of NASA" Wikipedia page (https://en.wikipedia.org/wiki/Budget_of_NASA):

(https://upload.wikimedia.org/wikipedia/en/1/1a/NASA_budget_linegraph_BH.PNG)

The trend for NASA's budget since 1991 has been a decrease both in 2014 Constant Dollars (a way to take into account inflation) and as a percentage of the Federal Budget.

From Wikipedia regarding Space Station Freedom (https://en.wikipedia.org/wiki/Space_Station_Freedom):

Quote
NASA signed final ten-year contracts for developing the Space Station in September 1988, and the project was finally moving into the hardware fabrication phase.

Which corresponds with the bump starting in 1988. And not that the DSG would require the funding profile of the ISS, but NASA's overall budget would have to take into account operational funding for one or more yearly SLS and Orion flights (and all of the production associated with them), as well as the production of the DSG hardware itself, and the DSG operational budget.

If the official goal becomes to land humans back on the Moon again, then you have to add development for all of that hardware, as well as funding the production of more SLS and Orion required to support the planned missions - and all of the funding required for ongoing operations (including the permanent staff required to be kept between flights).

We should get a hint about whether this is a possibility soon, when NASA responds back to the NSC.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: UltraViolet9 on 10/27/2017 06:39 pm
But yes, they need some sort of yearly increase(in nominal terms) in order to fund additional exploration elements ultimately totaling several billion dollars on an annual basis.

That, or a wedge has to be carved out of the SLS/Orion/GSE budget approaching $4B/yr.  Based on FY 2022 and STS experience, that does not seem possible without retiring one or both of those flight elements.

Without a plus-up or SLS/Orion/GSE retirement, it's hard to see much of a budget wedge opening up for DSG and/or lunar landers until after ISS retirement in 2024-2028 or later.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: yg1968 on 10/28/2017 02:45 pm
European space officials outline desired contribution to Deep Space Gateway:
http://spacenews.com/european-space-officials-outline-desired-contribution-to-deep-space-gateway/
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: redliox on 10/28/2017 03:31 pm
European space officials outline desired contribution to Deep Space Gateway:
http://spacenews.com/european-space-officials-outline-desired-contribution-to-deep-space-gateway/

In that article their emphasis seems to be on a space tug, presumably SEP.  Might be within their capability.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: yg1968 on 11/04/2017 02:56 am
NASA issues study contracts for Deep Space Gateway element:
http://spacenews.com/nasa-issues-study-contracts-for-deep-space-gateway-element/
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: calapine on 11/04/2017 08:25 pm
European space officials outline desired contribution to Deep Space Gateway:
http://spacenews.com/european-space-officials-outline-desired-contribution-to-deep-space-gateway/

In that article their emphasis seems to be on a space tug, presumably SEP.  Might be within their capability.

As per a CNES study Ariane 6 could deliever 6 tons in 3 months (chemical) or 10 tons in 1 year (SEP) to the DSG.

Should be good enough to deliver entire modules.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: brickmack on 11/07/2017 05:28 pm
Got a link to that study? 3 months seems awful long for chemical unless they're using some fancy low energy transfer (but then 6 tons sounds low...)
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 11/07/2017 05:34 pm
Got a link to that study? 3 months seems awful long for chemical unless they're using some fancy low energy transfer (but then 6 tons sounds low...)
Quick 3day transfer to DSG is about 3.7km/s, slow 3 month transfer is about 3.1 km/s.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: envy887 on 11/07/2017 11:17 pm
Got a link to that study? 3 months seems awful long for chemical unless they're using some fancy low energy transfer (but then 6 tons sounds low...)
Quick 3day transfer to DSG is about 3.7km/s, slow 3 month transfer is about 3.1 km/s.

3.1 km/s only gets it a Hohmann transfer to EML1 altitudes, how does it insert to NRHO?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: TrevorMonty on 11/08/2017 01:56 am
Got a link to that study? 3 months seems awful long for chemical unless they're using some fancy low energy transfer (but then 6 tons sounds low...)
Quick 3day transfer to DSG is about 3.7km/s, slow 3 month transfer is about 3.1 km/s.

3.1 km/s only gets it a Hohmann transfer to EML1 altitudes, how does it insert to NRHO?
I was thinking of EML1, not sure about NRO.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Patchouli on 11/08/2017 05:06 am
Got a link to that study? 3 months seems awful long for chemical unless they're using some fancy low energy transfer (but then 6 tons sounds low...)
Quick 3day transfer to DSG is about 3.7km/s, slow 3 month transfer is about 3.1 km/s.

Why even bother with such a slow transfer when the 3 day one only requires 600 m/sec more delta V?
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: calapine on 11/08/2017 10:55 am
Got a link to that study? 3 months seems awful long for chemical unless they're using some fancy low energy transfer (but then 6 tons sounds low...)

Sure:

https://www.researchgate.net/profile/Richard_Epenoy/publication/318562120_Ariane_6_and_Space_Tugs_An_Enabler_for_European_Exploration_Missions/links/59ddd512a6fdcc276fba79b6/Ariane-6-and-Space-Tugs-An-Enabler-for-European-Exploration-Missions.pdf
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Proponent on 11/08/2017 12:38 pm
Why even bother with such a slow transfer when the 3 day one only requires 600 m/sec more delta V?

When the delta-V is comparable to or greater than the effective exhaust velocity, a small change can have a pretty big impact on payload.

For example, suppose a Centaur (Isp 450.5 s, inert mass 2,316 kg, propellant mass 20,830 kg) is the trans-lunar injection stage.  Assuming residuals of 0.5%, I get a payload 18,100 kg to 3.1 km/s but just 13,500 to 3.7 km/s.  In other words, lowering the delta-V by 13% increases the payload by 34%.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Proponent on 01/27/2019 08:35 pm
Bob Zubrin is totally not on board. I'm shocked <video link elided -- Proponent>

Thanks much -- that was actually quite interesting.  Zubrin tears into DSG, pointing out, among other things, that never before in the history of planning for missions to Mars (or the moon), dating back to von Braun, has anyone said that a cis-lunar station is desirable.

Though I believe Zubrin's general point is very much correct, I have recently found an explicit example of a recommendation to build a station in lunar orbit as a way station to the lunar surface.  It's an interesting piece of out-of-the-box thinking produced by Goodyear Aircraft in 1962,  Aside from rotating inflatable stations in both LEO and LLO lunar orbit, it depended on Gemini spacecraft, Titan launch vehicles and lots and lots of Agena stages.

EDIT:  Replaced "LLO" with "lunar orbit," per Steven Pietrobon's precis (https://forum.nasaspaceflight.com/index.php?topic=43108.msg1905800#msg1905800), below.
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Steven Pietrobon on 01/28/2019 06:26 am
Very interesting. Their space station mass (both LEO and Lunar) is only 3086 kg! The Lunar station is at an altitude of 1600 km. After expansion, the station would have a 12.2 m diameter. The study even has a budget! Total cost is $3B. Total number of Titan II's is 1815 to 1968!
Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: tea monster on 01/28/2019 10:12 am
I thought this was really cool. I did a quick render of what the ship may have looked like on the surface. The Gemini is from NASA's 3D Resource page.

Title: Re: ASAP on board with NASA's DSG as stepping stone to Mars
Post by: Robotbeat on 02/06/2019 03:19 pm
A couple of notes on DSG:

Quote
Crusan: "for the first time ever, we have refueling baselined in our human space flight architecture."  Finally. Whoo hoo!!  #leag2017

https://twitter.com/george_sowers/status/917744545340764161

Quote
Jason Crusan asked how DSG is fueled. His answer: "I do not care where the fuel comes from" for Deep Space gateway. #LEAG2017

https://twitter.com/NASAWatch/status/917743640730132480
*cough* Salyut 7, Mir, ISS *cough*