Author Topic: ASAP on board with NASA's DSG as stepping stone to Mars  (Read 38504 times)

Offline UltraViolet9

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #100 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.

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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.

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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.

« Last Edit: 10/14/2017 01:17 AM by UltraViolet9 »

Offline savuporo

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #101 on: 10/15/2017 02:32 AM »
Bob Zubrin is totally not on board. I'm shocked

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Offline Steven Pietrobon

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #102 on: 10/15/2017 06:46 AM »
That was a really great panel. A lot better than some of the panels at the IAC!
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Offline Proponent

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #103 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.


Offline TrevorMonty

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.

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Offline savuporo

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #105 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.

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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
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Online ncb1397

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #106 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.

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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.

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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.



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.
« Last Edit: 10/15/2017 09:17 PM by ncb1397 »

Online Coastal Ron

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #107 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"

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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.

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...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.

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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 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, so when delays occurred they still were paid (like during the Columbia stand down)

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

What the heck does that mean?

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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.

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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.
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Offline UltraViolet9

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #108 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.

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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...

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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.

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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.
« Last Edit: 10/16/2017 12:16 AM by UltraViolet9 »

Offline Khadgars

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #109 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.

Offline Proponent

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #110 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.

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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?
« Last Edit: 10/16/2017 07:11 PM by Proponent »

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #111 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.

Online Coastal Ron

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #112 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

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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?
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Online ncb1397

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #113 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.

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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.
« Last Edit: 10/17/2017 06:56 PM by ncb1397 »

Offline whitelancer64

@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.
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Online Lars-J

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #115 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.

Offline UltraViolet9

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #116 on: 10/17/2017 08:40 PM »
13 payloads

No.

Only five are partially or fully funded through HEOMD.

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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.

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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.

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$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.
« Last Edit: 10/19/2017 01:47 AM by UltraViolet9 »

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #117 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.
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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #118 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... :(
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Offline Patchouli

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Re: ASAP on board with NASA's DSG as stepping stone to Mars
« Reply #119 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.
« Last Edit: 10/18/2017 02:18 AM by Patchouli »

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