Commercial space's role in Exploration Gateway station

[Political Hack Wannabe]

So, in the recent thread about Commercial Crew downselect, there was a short discussion about what role commercial should play in BEO spaceflight.

I am curious as to what people think are the possibles, and what are the desirables. 

As I see it there are the following options to consider (and these are not all mutually exclusive, although some are)

Traditional NASA structure, with Traditional NASA resuppply
COTS/CRS style resupply
Mixed Structure (some traditional NASA, some commercial pieces)
Non-NASA operator (NASA starts development of it, but also starts from day 1 to finding another party, who will do the operations of most of it)
Pure prize options (NASA puts up a prize for deployment and 1 year operations of it)
 
Other thoughts/ideas/comments? 

[tigerade]

Lets assume 3 things:

1. The CRS program is successful
2. The commercial crew program is successful
3. The exploration gateway is approved and built in a 10-20 year timeframe.

Ok, so we have commercial crew and cargo both online.  However the exploration gateway would very likely be built by NASA, as they have the most experience with this sort of thing.  If Bigelow does well, I could see maybe some sort of Bigelow module being added on.  Anyway, yes if commercial crew and cargo were both available, NASA would be crazy not to use it.  I am not sure about the orbital mechanics of getting something out to L1 or L2 or wherever this gateway will be.  But I'm sure that commercial companies could probably do something to compensate... I think.

So my answer is COTS/CRS resupply, with commercial crew missions, and traditional NASA structure and operation, with possibility of an additional commercial pieces added on.  This is fun to imagine, but it's really too far away to know for sure. 

[Political Hack Wannabe]

Tigerade - Why would you want to, for lack of a better phrase, tack commercial on at the end?  Why not try and find a way to integrate commercial from day one? 

[tigerade]

Well, I could see it going in either direction.  The whole structure could be built by NASA or other governmental hands.  Or, they could plan to integrate a commercial module in the plan.  It is up to them on what they want to do.

[Political Hack Wannabe]

I understand its up to them. 

I am asking what you think about that - is it a good idea or bad idea, and why?

[baldusi]

On the Dragon's return press conference Alan Lindenmoyer did say something along the lines that they where considering SpaceX's help on explorations. It has been discussed here to death, if a Falcon Heavy could push a Dragon to EML2. And Dragon is going to get BEO upgrades. So it is possible for Dragon, to offer something along the lines of COTS for an EML2 Cargo Resupply. I'm not sure about Crew, because transit times might get too long for Crewed Dragon. But Cargo Dragon shouldn't be that far fetched. If they use ISS legacy modules and ops, the ISS Cargo Dragon would be a lot similar, so it would be ridiculous not to take advantage of all the work done. If they don't use CBM, and use NDS also for cargo, they could demonstrate an Robotic Orion/Cargo Dragon on EML2 even before the first module is there.
I do wonder, if this is a strategy that NASA will follow, if it won't impact on the Commercial Crew selection. I mean, it's quite clear that Dragon/Falcon Heavy is very close be able to do cargo to EML2. It's not very clear if they can do crew, but it is possible with some evolution. Since CST-100 evolved from the competition with Orion, I'm sure it could be upgraded to do cargo and/or crew with relatively little risk, but it would need a new launcher. Either a human rated Delta IV Heavy, an Atlas V Heavy or an Atlas Phase 2. Could obviously use Falcon Heavy, too, but I guess the idea would be not to have to rely on a single supplier, if possible.
Dream Chaser isn't designed for BEO, and I doubt it could be upgraded to tolerate a lunar reentry, so, in that sense, it would seem like a dead end to LEO.
I ignore the Blue Origin entry, but if they use the biconic side for reentry, it won't tolerate lunar reentry.
Liberty capsule could obviously do BEO very well, but I don't believe Liberty rocket can send it to EML2. So, in that sense, it could be a good candidate for the capsule's future, but the LV has not many growth options. Plus, the Vulcain 2 can't restart, which is probably a worse problem. And it's going to be a very thorny legal problem for LM to actually develop a BEO SM for Liberty without using Orion's systems, which require special legislation to be able to compete.
I do want to add, that given a powerful enough LV, Cygnus is probably able to do a cargo mission to EML2.
the problem with international partners, is that Ariane 5 and H-IIB can't push ATV and HTV beyond LEO, so it would mean a new capsule development or a new LV.
I don't know what the Angara 5 will be able to do, but I'm sure Soyuz LV can't be increased significantly, and to evolve Soyuz for EML2 would need something like launching an EDS on a Proton or Angara 5. Plus, they might want to use the PPTS.
In other words, the ISS partners are all very far from being able to do any logistics role to EML2.
In other words, from my perspective, if NASA expects to evolve commercial to EML2, Dragon, CST-100 and possibly Cygnus are the most likely candidates to support now.

[MikeAtkinson]

Potentially it is a good idea to use CRS and commercial crew spacecraft for gateway support.

But: commercial crew vehicles do not have sufficient delta-v, and would need an upgrade of all their systems. CRS vehicles probably have too little payload capacity (even with a FH launch) and Dragon does not have the delta-v to return cargo to earth.

[Edit: I would love to be proved wrong here!]

The main reason it is potentially a good idea is that it might be cheaper as there would be synergies with ISS support.

[Political Hack Wannabe]

But why limit commercial involvement to JUST resupply, or crew transportation?

[rklaehn]

Potentially it is a good idea to use CRS and commercial crew spacecraft for gateway support.

But: commercial crew vehicles do not have sufficient delta-v, and would need an upgrade of all their systems. CRS vehicles probably have too little payload capacity (even with a FH launch) and Dragon does not have the delta-v to return cargo to earth.

[Edit: I would love to be proved wrong here!]

The main reason it is potentially a good idea is that it might be cheaper as there would be synergies with ISS support.

Assuming a delta-v from LEO to EML2 of 3.43 km/s, a falcon heavy should be able to get a dragon with a weight of 10t to EML2. The GTO payload of falcon heavy is supposed to be 19t, and EML2 is less than 1km/s from GTO.

On the way back you would have to rely on the dragon propulsion system to get the dragon on an intercept with the earth atmosphere. But getting from EML2 back to a highly elliptical orbit that intercepts the earth atmosphere just requires ~1km/s if you do it in one burn, and even less if you do a powered moon flyby.

So getting back from EML2 to earth is well within the capability of the dragon.

Arguably, flying a dragon to EML2 and back would be a good way to spend the initial falcon heavy launch. They will have many used dragons by the time falcon heavy lauches. It would prove multiple things like deep space operations and return from almost hyberbolic velocity. And it would be a first.

edit:

getting the dragon to and from EML2 would probably be easiest doing a three impulse transfer: an initial burn from LEO to the lunar vicinity of 3.142km/s, which would be done by the falcon heavy upper stage, a burn close to the moon of 0.184km/s, and a burn to enter EML2 of 0.148km/s. The latter two would have to be done by the dragon. On the way back you do everything in reverse.

So the total delta-v from LEO is 3.142km/s for the falcon heavy upper stage, and 0.664km/s for the dragon.

To get a station to EML2 you would probably use a weak stability boundary trajectory. That takes about 3.1km/s in a single burn at the beginning of the mission So you should be able to launch a pretty reasonable space station module (~16t) directly to EML2 using a falcon heavy.

[MikeAtkinson]

But why limit commercial involvement to JUST resupply, or crew transportation?

Resupply and crew rotation is probably 70% of the total cost, and they are the places were big savings are possible.

The three other major costs are I think:

    - building the gateway module(s).
    - transporting them from LEO to L2.
    - operating the gateway.

Building the gateway module(s) based on ISS module designs is probably the cheapest solution, it is probably easiest for ISS like contracting arrangements to be used.

There does not seem to be a method of getting them from LEO to L2. Integration in LEO (possibly attached to ISS) followed by a SEP tug is one way that has been suggested. But whatever the method I think it unlikely that a COTS style program would lead to cost savings.

NASA is really good at ops, and would want control and oversight anyway. I would not think there are great cost savings possible from anyone else than NASA doing it.

[All IMHO naturally]

[muomega0]

On the Dragon's return press conference Alan Lindenmoyer did say something along the lines that they where considering SpaceX's help on explorations. It has been discussed here to death, if a Falcon Heavy could push a Dragon to EML2. And Dragon is going to get BEO upgrades. So it is possible for Dragon, to offer something along the lines of COTS for an EML2 Cargo Resupply. I'm not sure about Crew, because transit times might get too long for Crewed Dragon. But Cargo Dragon shouldn't be that far fetched. If they use ISS legacy modules and ops, the ISS Cargo Dragon would be a lot similar, so it would be ridiculous not to take advantage of all the work done. If they don't use CBM, and use NDS also for cargo, they could demonstrate an Robotic Orion/Cargo Dragon on EML2 even before the first module is there.
I do wonder, if this is a strategy that NASA will follow, if it won't impact on the Commercial Crew selection. I mean, it's quite clear that Dragon/Falcon Heavy is very close be able to do cargo to EML2. It's not very clear if they can do crew, but it is possible with some evolution. Since CST-100 evolved from the competition with Orion, I'm sure it could be upgraded to do cargo and/or crew with relatively little risk, but it would need a new launcher. Either a human rated Delta IV Heavy, an Atlas V Heavy or an Atlas Phase 2. Could obviously use Falcon Heavy, too, but I guess the idea would be not to have to rely on a single supplier, if possible.
Dream Chaser isn't designed for BEO, and I doubt it could be upgraded to tolerate a lunar reentry, so, in that sense, it would seem like a dead end to LEO.
I ignore the Blue Origin entry, but if they use the biconic side for reentry, it won't tolerate lunar reentry.
Liberty capsule could obviously do BEO very well, but I don't believe Liberty rocket can send it to EML2. So, in that sense, it could be a good candidate for the capsule's future, but the LV has not many growth options. Plus, the Vulcain 2 can't restart, which is probably a worse problem. And it's going to be a very thorny legal problem for LM to actually develop a BEO SM for Liberty without using Orion's systems, which require special legislation to be able to compete.
I do want to add, that given a powerful enough LV, Cygnus is probably able to do a cargo mission to EML2.
the problem with international partners, is that Ariane 5 and H-IIB can't push ATV and HTV beyond LEO, so it would mean a new capsule development or a new LV.
I don't know what the Angara 5 will be able to do, but I'm sure Soyuz LV can't be increased significantly, and to evolve Soyuz for EML2 would need something like launching an EDS on a Proton or Angara 5. Plus, they might want to use the PPTS.
In other words, the ISS partners are all very far from being able to do any logistics role to EML2.
In other words, from my perspective, if NASA expects to evolve commercial to EML2, Dragon, CST-100 and possibly Cygnus are the most likely candidates to support now.

Forcing any of the current capsule configurations or LVs, individually, to head directly to the Exploration Gateway at L2 will be very inefficient.  Just look what happened to Orion trying to be multipurpose.

IOW, as you point out, nothing really fits the current inflexible HLV Gateway architecture as everything must be modified as equipment is moved to an environment and life duration other than its original design intent.

Further, ISS partners have launch vehicles that could launch supplies or fuel to LEO.

Staging mass or prop in LEO provides a significant amplification factor for the transfer to BEO, and using high ISP prop, reduces IMLEO. 

Since the missions are greater than 70% fuel, a LEO depot would enable staging of prop and hardware to fit the "existing" fleet and offers significant advantages.

So with 3B (?) piece of hardware, a LEO depot could provide all the prop and supplies for the BEO transfer stage launched empty on, i guess, the SLS, or  since it would be so light, a smaller LV.

One could also attach one the Cots capsules as the "life boat" for direct return to earth, or simply return to ISS with say the  transhab first, then to earth.

So if one wants cost savings.....

Vast number of potential opportunities.....

[Political Hack Wannabe]

Building the gateway module(s) based on ISS module designs is probably the cheapest solution, it is probably easiest for ISS like contracting arrangements to be used.

I'll tend to agree with you in general. HOWEVER, I would submit that you have a node with 6 ports, and currently only 2 of those ports are formally assigned (with a 3rd one potentially assigned to International partners, and if you insist, one assigned to Orion).  So we have somewhere between 2 and 4 ports that are unused.  Why not reach out to commercial companies, and see what they might use them for?

There does not seem to be a method of getting them from LEO to L2. Integration in LEO (possibly attached to ISS) followed by a SEP tug is one way that has been suggested. But whatever the method I think it unlikely that a COTS style program would lead to cost savings.

Let me offer one integration plan that would at least lend itself to being more commercial - instead of using SEP tug to transfer it out, use a CPS/depot option.  Then, the depot you have in LEO can potentially facilitate more resupply missions at lower cost as well. 

NASA is really good at ops, and would want control and oversight anyway. I would not think there are great cost savings possible from anyone else than NASA doing it.

[All IMHO naturally]

You've missed a vital part in all of this - utilization.  What is the utilization plan, and what about commercial playing a part in the utilization?  (Yes, this will have an impact on ops)

[FinalFrontier]

So, in the recent thread about Commercial Crew downselect, there was a short discussion about what role commercial should play in BEO spaceflight.

I am curious as to what people think are the possibles, and what are the desirables. 

As I see it there are the following options to consider (and these are not all mutually exclusive, although some are)

Traditional NASA structure, with Traditional NASA resuppply
COTS/CRS style resupply
Mixed Structure (some traditional NASA, some commercial pieces)
Non-NASA operator (NASA starts development of it, but also starts from day 1 to finding another party, who will do the operations of most of it)
Pure prize options (NASA puts up a prize for deployment and 1 year operations of it)
 
Other thoughts/ideas/comments? 

Actually rather glad to see you bring this up.

About two years ago we discussed this in depth during the Space Policy battles. The "flexible path" concept was a big deal on here and it involved either all commercial or heavily EELV based paths.

BEO stations maintained by commercial providers were a very large part of that path. I will see if I can dig up some of the old threads for reference on this discussion.


IMO its about time it be brought up again with recent success's in the commercial field.

[rklaehn]

Forcing any of the current capsule configurations or LVs, individually, to head directly to the Exploration Gateway at L2 will be very inefficient.  Just look what happened to Orion trying to be multipurpose.

Dragon is designed for beyond LEO. The heat shield can survive a reentry from hyperbolic velocity, according to elon musk.

Falcon heavy has sufficient delta-v to send a dragon to EML2. So assuming falcon heavy flies there is a commercial off the shelf system for resupply of an EML2 gateway.

Whether you can fly crew depends on if you can man-rate the falcon heavy.

[MikeAtkinson]

You've missed a vital part in all of this - utilization.  What is the utilization plan, and what about commercial playing a part in the utilization?  (Yes, this will have an impact on ops)

I really can't see significant commercial utilization. Even if the gateway enabled significant business the percentage of revenue that would go to the  gateway would be small. I think that most (>90%) of the gateway costs will have to be paid by NASA and the other space agencies.

I assume utilization will be mostly support for human exploration (moon, NEA, Mars) with a bit of science and teleoperation of lunar rovers. Commercial operation would be the occasional tourist and maybe commercial asteroid mining support (Planetary Resources).

[Lar]

I assume utilization will be mostly support for human exploration (moon, NEA, Mars) with a bit of science and teleoperation of lunar rovers. Commercial operation would be the occasional tourist and maybe commercial asteroid mining support (Planetary Resources).

If Planetary Resources plans come to fruition won't there be an increasing amount of utlization over time as they ramp up their operations (each successfully exploited asteroid funds another set of hardware while the first hardware goes off and starts exploiting the next one)? That's the hope anyway.

Also would ACES have a role to play here? A reusable upper stage that's mostly tankage with the ability to transfer propellant both to, and from it, seems pretty useful. Especially once PRI starts supplying propellant in orbit from the water side of their operations.

Can F9H launch ACES? Would Elon want to? Or would SpaceX make a reusable stage of their own? (probably!)

[MikeAtkinson]

Assume Planetary Resources are spending $1B/year, most of that would go on bringing back the asteroids. Some might be used to send astronauts to set up the processing plant, say maybe $250M, but most of that would be on launch, spacecraft, ops at the processing plant, etc. Maybe $20M would be spent on gateway services.

Similarly of a tourist spending $50M for a trip to the Moon, maybe a few million would be spent on gateway services.

I would be very surprised if commercial income exceeded $100M/year before 2030, I would estimate costs of maybe $1B/year (including amortized development) for a man-tended (i.e. not permanently manned) gateway.

[Political Hack Wannabe]

You've missed a vital part in all of this - utilization.  What is the utilization plan, and what about commercial playing a part in the utilization?  (Yes, this will have an impact on ops)

I really can't see significant commercial utilization. Even if the gateway enabled significant business the percentage of revenue that would go to the  gateway would be small. I think that most (>90%) of the gateway costs will have to be paid by NASA and the other space agencies.

I assume utilization will be mostly support for human exploration (moon, NEA, Mars) with a bit of science and teleoperation of lunar rovers. Commercial operation would be the occasional tourist and maybe commercial asteroid mining support (Planetary Resources).

You may not be able to, but that doesn't mean they don't exist.  I could forsee a few private rovers on the moon, so having a presence at Waypoint may be preferable for them.  Or maybe there will be interest in pursuing some SBSP work (I tend to be more pessimistic about this). 

The point is, you have space station, lets try some experiments with it, that aren't just science. 

Additionally, there is a longer term issue, which is coming to a head with ISS and may very well be an issue for Waypoint.  And that is, how do we avoid the trap of building infrastructure, and then having to abandon it to go and do the next thing (like we did with Apollo, like we talked about doing for ISS and Constellation).  This is especially bad when we want to use it, but don't have the budget for it. 

To get out of that Catch-22 situation, we need to find someway to transition that infrastructure to a cost neutral situation.  Commercialization is one way to address this. 

An example of the other side of this is of course what we've done with Comm sats and launch vehicles (to a degree).

[Political Hack Wannabe]

I would be very surprised if commercial income exceeded $100M/year before 2030, I would estimate costs of maybe $1B/year (including amortized development) for a man-tended (i.e. not permanently manned) gateway.

How does that not put us back into the same situation we are in with ISS?

[PeterAlt]

Lets assume 3 things:

1. The CRS program is successful
2. The commercial crew program is successful
3. The exploration gateway is approved and built in a 10-20 year timeframe.

Ok, so we have commercial crew and cargo both online.  However the exploration gateway would very likely be built by NASA, as they have the most experience with this sort of thing.  If Bigelow does well, I could see maybe some sort of Bigelow module being added on.  Anyway, yes if commercial crew and cargo were both available, NASA would be crazy not to use it.  I am not sure about the orbital mechanics of getting something out to L1 or L2 or wherever this gateway will be.  But I'm sure that commercial companies could probably do something to compensate... I think.

So my answer is COTS/CRS resupply, with commercial crew missions, and traditional NASA structure and operation, with possibility of an additional commercial pieces added on.  This is fun to imagine, but it's really too far away to know for sure. 

I have no problems assuming the first two. It's the third one that I am uneasy about happening until I see something that there's at least a desire to make this possible. As of now, the Exploration Gateway is nothing but talk by a few contractors and some visionaries Within NASA. If this would seriously happen, there would be the precursor cost and budget studies before an official presidential request. It's not there yet. And with NASA's tight budget with everything currently on its plate, I don't see this happening any time soon, unless the politicians show some backbone to pull the strings to make this happen.

That said, commercial space can get things started ahead of EG by sending their own hardware to ISS. That hardware could eventually be moved to the EG. ISS and LEO is an obvious starting point and staging area for all operations, including commercial, that could eventually migrate into BEO.

[Lar]

That said, commercial space can get things started ahead of EG by sending their own hardware to ISS. That hardware could eventually be moved to the EG. ISS and LEO is an obvious starting point and staging area for all operations, including commercial, that could eventually migrate into BEO.

Is the high inclination orbit ISS is in a drawback at all, though? I agree that it's a great place to stage in terms of the equipment, people and expertise already there. But how much delta V is wasted due to inclination changes needed?? I'm no orbital mechanic so forgive me if that's a not very well informed question.

[QuantumG]

Lost delta-v doesn't compare to the lost productivity of trying to do it without the ISS.

[Lar]

Lost delta-v doesn't compare to the lost productivity of trying to do it without the ISS.

True, even when propellant all comes from earth. But especially true if it's brought to LEO in tankers filled up by PRI operations... I suppose the topic of ISS's inclination has been beat to death elsewhere. But I'm a noob here, and there's so much to read here.

[jnc]

But how much delta V is wasted due to inclination changes needed??

Lots. See here for more, but for an example: "if the angular change is equal to 60 degrees, the required change in velocity is equal to the current velocity".

To see why, think about a 90 degree plane change. In rough terms, you have to kill the x-direction velocity completely, and take the y-direction velocity from 0 to orbital speed. (Actually, it's a bit more complex than that, but this gives a rough, intuitive sense for the magnitude needed.) That's 2 times the orbital velocity..

Noel

[Lobo]

On the Dragon's return press conference Alan Lindenmoyer did say something along the lines that they where considering SpaceX's help on explorations. It has been discussed here to death, if a Falcon Heavy could push a Dragon to EML2. And Dragon is going to get BEO upgrades. So it is possible for Dragon, to offer something along the lines of COTS for an EML2 Cargo Resupply. I'm not sure about Crew, because transit times might get too long for Crewed Dragon. But Cargo Dragon shouldn't be that far fetched. If they use ISS legacy modules and ops, the ISS Cargo Dragon would be a lot similar, so it would be ridiculous not to take advantage of all the work done. If they don't use CBM, and use NDS also for cargo, they could demonstrate an Robotic Orion/Cargo Dragon on EML2 even before the first module is there.
I do wonder, if this is a strategy that NASA will follow, if it won't impact on the Commercial Crew selection. I mean, it's quite clear that Dragon/Falcon Heavy is very close be able to do cargo to EML2. It's not very clear if they can do crew, but it is possible with some evolution. Since CST-100 evolved from the competition with Orion, I'm sure it could be upgraded to do cargo and/or crew with relatively little risk, but it would need a new launcher. Either a human rated Delta IV Heavy, an Atlas V Heavy or an Atlas Phase 2. Could obviously use Falcon Heavy, too, but I guess the idea would be not to have to rely on a single supplier, if possible.
Dream Chaser isn't designed for BEO, and I doubt it could be upgraded to tolerate a lunar reentry, so, in that sense, it would seem like a dead end to LEO.
I ignore the Blue Origin entry, but if they use the biconic side for reentry, it won't tolerate lunar reentry.
Liberty capsule could obviously do BEO very well, but I don't believe Liberty rocket can send it to EML2. So, in that sense, it could be a good candidate for the capsule's future, but the LV has not many growth options. Plus, the Vulcain 2 can't restart, which is probably a worse problem. And it's going to be a very thorny legal problem for LM to actually develop a BEO SM for Liberty without using Orion's systems, which require special legislation to be able to compete.
I do want to add, that given a powerful enough LV, Cygnus is probably able to do a cargo mission to EML2.
the problem with international partners, is that Ariane 5 and H-IIB can't push ATV and HTV beyond LEO, so it would mean a new capsule development or a new LV.
I don't know what the Angara 5 will be able to do, but I'm sure Soyuz LV can't be increased significantly, and to evolve Soyuz for EML2 would need something like launching an EDS on a Proton or Angara 5. Plus, they might want to use the PPTS.
In other words, the ISS partners are all very far from being able to do any logistics role to EML2.
In other words, from my perspective, if NASA expects to evolve commercial to EML2, Dragon, CST-100 and possibly Cygnus are the most likely candidates to support now.

(Note, some of this is from the commercial crew down select thread, as I posted it there before I saw this more applicable thread)

I think it depends on if it would be staffed year around, or only during a mission.  How much cargo that’s needed would depend on that.  Obviously all the crew rotation would be done by Orion on SLS.  SLS and Orion would be the only man-rated capsule and LV that could get out there, at first anyway.  And I think NASA would want to keep it that way for obvious reasons of justifying Orion and SLS for BLEO operations.  (I don't think they'd want some one to come along and do it faster and cheaper).

Now, SpaceX here is interesting.  If SpaceX gets a commercial crew contract, then F9 and Dragon will be man rated. Which means FH should basically be man-rated by default.  So SpaceX could then possibly offer a commercial crew service to EML2.  Dragon (or Dragonrider) should have the capability for that long in space.  Might need some upgrades like a bathroom, though.  NASA might be interested in that as a backup to SLS/Orion, but like I said, I doubt they’d want to have anything but SLS/Orion delivering crews out there, unless there was some problem and SLS/Orion was grounded. 

However, SpaceX with Dragon and FH would be in a very good position to offer cargo support to EML2.  FH could get a loaded cargo Dragon and trunk out there, and probably for a pretty reasonable price.  Maybe around 10mt of cargo? Both pressurized and unpressurized.   I understand that Dragon is designed to handle those reentry speeds anyway.  (at least Musk has said so I think) And with the trunk and solar panels, Dragon can operate for the trip out and trip back.
CST-100 on the other hand would need to be upgraded with a trunk and solar panels or fuel cells, because I understand it’s only designed for a few hours of battery life?  Just enough to get a crew to the ISS, and then to get them back home.  It’s batteries would die on the way out to EML2 if launched on an Atlass 551 or D4H.  I also don’t know if it’s heat shield could handle BLEO reentry speeds without being upgraded too.
I believe DC is incapable of BLEO reentry speeds, being a space plane (please correct if that’s wrong). 
I don’t know enough about Liberty to know if that LV could get a capsule out to EML2.  I understand it’s an LV more optimized for LEO operations, but I think they are advertising it can sent payloads to GTO, so maybe it could.  Be interesting to know how much cargo it could get out there on top of the CSM, if it could any at all.  So don’t know about them being a player out there.  if it can only just barely get the capsule out there, it won't be much good as a cargo carrier.

So, if NASA is interested in any commercial cargo service to an EML2 station, SpaceX would probably be about the only player there.  And they could probably do it pretty cheap compared to NASA using SLS.  ULA could offer service for propellant deliveries if the EML2 gateway was a depot too.   However, NASA may just launch a large MPLM along with Orion to EML2 and have that be the cargo carrier during a crew rotation if indeed the EML2 gateway will be staffed at times other than an active mission.  A reason to get the SLS flight rate up a little more, and not mess around with commercial cargo.

[go4mars]

curious as to what people think are the possibles,
and what are the desirables. 

I think these are all possible, but I'll rank them in order of desireability from my perspective (which aims for maximum return for tax dollars in current environment).

Note that I changed this first one:

Pure prize option (NASA pays only whoever accomplishes a specified goal first by any means).  If no credible effort from the private sector, then up the prize purse incrementally.

Non-NASA operator (NASA specifies requirements, non-NASA companies supply solutions however they want to (NASA doesn't design the solutions))

Mixed Structure (some traditional NASA, some commercial pieces)

COTS/CRS style resupply

Traditional NASA structure, with Traditional NASA resuppply

[Celebrimbor]

I just don't think that manned space will pass any rational cost benefit analysis within commerical companies in the next few decades. Commercial will only put humans in space if they are explicitly paid to do so...

Therefore their role in EG would not be in utilization, it would be in resupply & crew transfer contracts.

I can see commerical space getting much more involved with a purely robotic fuel depot than EG.

[cosmicvoid]

Maybe I'm missing something here, but I don't understand why all the references are to EML2.  ISTM that EML1 would be a preferable location.  Is there some reason why not?

What are the pros and cons of the two choices?

[rklaehn]

Maybe I'm missing something here, but I don't understand why all the references are to EML2.  ISTM that EML1 would be a preferable location.  Is there some reason why not?

What are the pros and cons of the two choices?

EML2 is easier to get to from a delta-v point of view: 3.43 km/s vs. 3.77km/s. The practical difference is even bigger since entering EML1 requires a relatively large maneuver many days after launch, that has to be done by the spacecraft using storable propellants. The upper stage can't do it because of boiloff.

For entering EML2 on the other hand most of the delta-v can be provided by the much more efficient upper stage just hours after launch, so boiloff is not a problem.

And it is further out in the earth gravity well, so it is closer to earth C3=0, which is advantageous for missions beyond earth (asteroid or mars). That is why it was baselined by the ULA exploration papers from 2009.

By the way: communication to EML2 is not a problem. You can put the station in a halo orbit around EML2 that has a direct line of sight to earth.

The downside is that the transit time to EML2 is higher, which requires more consumables for a crewed flight. But for an exploration gateway that is manned for months, or as a staging area for missions that last years, it does not really make a difference.

[cosmicvoid]

(snip)
By the way: communication to EML2 is not a problem. You can put the station in a halo orbit around EML2 that has a direct line of sight to earth.
(snip)

Ok, thanks, I get it now.  The orbit around EML2 for direct sight of earth answers my thought about comm problems.

[A_M_Swallow]

By the way: communication to EML2 is not a problem. You can put the station in a halo orbit around EML2 that has a direct line of sight to earth.

Although you do have to add delta-V to enter the HALO orbit and rendezvous with the spacestation.

[Jason1701]

Maybe I'm missing something here, but I don't understand why all the references are to EML2.  ISTM that EML1 would be a preferable location.  Is there some reason why not?

What are the pros and cons of the two choices?

EML2 is easier to get to from a delta-v point of view: 3.43 km/s vs. 3.77km/s. The practical difference is even bigger since entering EML1 requires a relatively large maneuver many days after launch, that has to be done by the spacecraft using storable propellants. The upper stage can't do it because of boiloff.

For entering EML2 on the other hand most of the delta-v can be provided by the much more efficient upper stage just hours after launch, so boiloff is not a problem.

And it is further out in the earth gravity well, so it is closer to earth C3=0, which is advantageous for missions beyond earth (asteroid or mars). That is why it was baselined by the ULA exploration papers from 2009.

By the way: communication to EML2 is not a problem. You can put the station in a halo orbit around EML2 that has a direct line of sight to earth.

The downside is that the transit time to EML2 is higher, which requires more consumables for a crewed flight. But for an exploration gateway that is manned for months, or as a staging area for missions that last years, it does not really make a difference.

Very interesting. Do you know the delta-vs to L1 and L2 from the lunar surface? That would be good to know for any manned lunar landings from the Gateway.

[Ben the Space Brit]

For me, cargo and propellent delivery to any putative gateway station is the #1 way they can contribute (although pre-placement of equipment at landing sites is a mid-term possibility).  What makes this valuable is that it would impell the development of BEO-capable commercial launch vehicles and the consequential reduction of costs to launch to EML-1.  This can only make it easier to explore and, ultimately, exploit, whatever viable resources the Moon may hold.

[luksol]

I think that when talking about private sector involvement the first question that has to be asked is why would they want to go there?

There has to be a reason for commercial companies to go there. I understand the resupply missions can be profitable, but only as long as NASA (or someone else) pays for it. Any further involvement depends on any other possibilities available at EML2, commercial, not scientific possibilities.

If such possibilities are to be found, then the commercial sector can participate in EML2 station construction, ops etc using their own resources rather than just being paid for by NASA.

In my opinion this is the first question that has to be answered.

[Ben the Space Brit]

I think that when talking about private sector involvement the first question that has to be asked is why would they want to go there?

It's a bit of a 'chicken or egg' question.  After all, until the commercial access capabilities are available, it won't be possible to go there.  So, as with ISS, NASA will have to be the "anchor tenant".  However, once the capability is there and more affordable, then the possibility emerges of operations like Planetary Resources following for their own reasons.  Until that capability is there, then reasons won't appear (at least not with profitable ROIs).

I suppose it is possible that some enterprising billionaire will take a risk but it isn't likely unless there is a major game-changing discovery or technological development.

[rklaehn]

Very interesting. Do you know the delta-vs to L1 and L2 from the lunar surface? That would be good to know for any manned lunar landings from the Gateway.

I think everything you need to know about getting from EML2 to the lunar surface should be in here:
http://www.ulalaunch.com/site/docs/publications/AffordableExplorationArchitecture2009.pdf

Edit: This should also be a reminder that commercial is not just spacex. If ULA was freed from the artificial restrictions by its parent companies, they could be very competitive with spacex.

They give a delta-v from the lunar surface to the EML2 gateway of 2650m/s (including gravity losses). It should be roughly the same going from EML2 to the lunar surface. But this of course depends a bit on where you want to land on the moon.

[rklaehn]

By the way: communication to EML2 is not a problem. You can put the station in a halo orbit around EML2 that has a direct line of sight to earth.

Although you do have to add delta-V to enter the HALO orbit and rendezvous with the spacestation.

Do you? When you pass EML2 you need to do a burn to cancel your velocity so you stay at EML2. Going directly to the halo orbit would just mean tweaking this burn a bit. I don't think you need additional delta-v. You might even save some delta-v.

In any case the halo "orbit" is not really an orbit but just a very slow (~28 day period) movement around EML2. You have the same semi-major axis and thus the same orbital period of EML2, but higher excentricity and a slightly inclined orbital plane relative to the orbital plane of the moon.

[MikeAtkinson]

Potentially it is a good idea to use CRS and commercial crew spacecraft for gateway support.

But: commercial crew vehicles do not have sufficient delta-v, and would need an upgrade of all their systems. CRS vehicles probably have too little payload capacity (even with a FH launch) and Dragon does not have the delta-v to return cargo to earth.

[Edit: I would love to be proved wrong here!]

The main reason it is potentially a good idea is that it might be cheaper as there would be synergies with ISS support.

Assuming a delta-v from LEO to EML2 of 3.43 km/s, a falcon heavy should be able to get a dragon with a weight of 10t to EML2. The GTO payload of falcon heavy is supposed to be 19t, and EML2 is less than 1km/s from GTO.

On the way back you would have to rely on the dragon propulsion system to get the dragon on an intercept with the earth atmosphere. But getting from EML2 back to a highly elliptical orbit that intercepts the earth atmosphere just requires ~1km/s if you do it in one burn, and even less if you do a powered moon flyby.

So getting back from EML2 to earth is well within the capability of the dragon.

Arguably, flying a dragon to EML2 and back would be a good way to spend the initial falcon heavy launch. They will have many used dragons by the time falcon heavy lauches. It would prove multiple things like deep space operations and return from almost hyberbolic velocity. And it would be a first.

edit:

getting the dragon to and from EML2 would probably be easiest doing a three impulse transfer: an initial burn from LEO to the lunar vicinity of 3.142km/s, which would be done by the falcon heavy upper stage, a burn close to the moon of 0.184km/s, and a burn to enter EML2 of 0.148km/s. The latter two would have to be done by the dragon. On the way back you do everything in reverse.

So the total delta-v from LEO is 3.142km/s for the falcon heavy upper stage, and 0.664km/s for the dragon.

To get a station to EML2 you would probably use a weak stability boundary trajectory. That takes about 3.1km/s in a single burn at the beginning of the mission So you should be able to launch a pretty reasonable space station module (~16t) directly to EML2 using a falcon heavy.

Now that SpaceX have put a figure of 12,000 kg on FH GTO performance it looks like my suspicions were correct.

[simonbp]

Just a note on trajectories: the propulsive lunar gravity-assist trajectory (two impulse after TLI) is a good combination of transfer time and delta-v. It is not, however, a free-return trajectory. The single-impulse lunar gravity-assist can be free-return, and so may be preferable for crew missions to L2. Two-impulse would still be the best option for return to Earth, though.

For getting the station to L2, a standard low-thrust spiral is more likely. It's by far the most optimized for a solar-electric transfer stage, and naturally cancels out any phasing and inclination effects from assembling the station at ISS. Even for a WSB trajectory, the mass of propellant required to send a proper station to L2 is probably large enough to justify the SEP stage (especially considering that they are apparently scaling the gateway to SLS).

WSB-type trajectories may be useful for cargo runs, though, and would need to be traded with the extra cost of a SEP stage. I would be curious what a Cygnus with extra solar arrays and an ion engine could haul to L2...

[pathfinder_01]

Now that SpaceX have put a figure of 12,000 kg on FH GTO performance it looks like my suspicions were correct.

For resupply FH and Delta heavy are enough.

When it comes to life support you are often volume limited. Not mass limied.

According to this: http://futureinspaceoperations.com/papers/HumanOps_Beyond_LEO_11_2010.pdf

A single dragon capsule with 10 meters cubed presurized volume would hold enough for a crew of 3-4 for about at most 180 days but likely more likely 60 due to volume.

A Cygnus with 18.9 meters volume 90 days. Dragon only masses 4mt dry so there is room to add a more massive service module.Cygnus is only 1.5Mt, so again room to add a serivce module(or more fuel tanks).

Moving the station is what will require SEP or multiple launches.

[rklaehn]

Just a note on trajectories: the propulsive lunar gravity-assist trajectory (two impulse after TLI) is a good combination of transfer time and delta-v. It is not, however, a free-return trajectory. The single-impulse lunar gravity-assist can be free-return, and so may be preferable for crew missions to L2. Two-impulse would still be the best option for return to Earth, though.

What is the advantage of a free return trajectory? Increased safety? At some point you will have to rely on your propulsion system.

But the single-impulse trajectory might be preferable for crew exchange because it is a bit quicker as well.

[Jason1701]

Just a note on trajectories: the propulsive lunar gravity-assist trajectory (two impulse after TLI) is a good combination of transfer time and delta-v. It is not, however, a free-return trajectory. The single-impulse lunar gravity-assist can be free-return, and so may be preferable for crew missions to L2. Two-impulse would still be the best option for return to Earth, though.

For getting the station to L2, a standard low-thrust spiral is more likely. It's by far the most optimized for a solar-electric transfer stage, and naturally cancels out any phasing and inclination effects from assembling the station at ISS. Even for a WSB trajectory, the mass of propellant required to send a proper station to L2 is probably large enough to justify the SEP stage (especially considering that they are apparently scaling the gateway to SLS).

WSB-type trajectories may be useful for cargo runs, though, and would need to be traded with the extra cost of a SEP stage. I would be curious what a Cygnus with extra solar arrays and an ion engine could haul to L2...

I have a trajectory question relating to this - if we wanted to land on the Moon from the Gateway, would there be a delta-v penalty to going to LLO before landing? How much?

Also, is the delta-v from each L-point to the lunar surface similar?

[rklaehn]

I have a trajectory question relating to this - if we wanted to land on the Moon from the Gateway, would there be a delta-v penalty to going to LLO before landing? How much?

Also, is the delta-v from each L-point to the lunar surface similar?

I think there is no penalty for entering LLO. But you don't want to stay in LLO for long because it takes some delta-v to stay in a predefined LLO because of the inhomogenous lunar gravity field.

Regarding the delta-v: L1 and L2 should be roughly similar. With L3, L4 and L5 there is a tradeoff between delta-v and transit time. You can get e.g. from L5 to LLO very cheaply (almost as cheap as from L1/L2), but it will take a long time (weeks).

[Jason1701]

I have a trajectory question relating to this - if we wanted to land on the Moon from the Gateway, would there be a delta-v penalty to going to LLO before landing? How much?

Also, is the delta-v from each L-point to the lunar surface similar?

I think there is no penalty for entering LLO. But you don't want to stay in LLO for long because it takes some delta-v to stay in a predefined LLO because of the inhomogenous lunar gravity field.

Regarding the delta-v: L1 and L2 should be roughly similar. With L3, L4 and L5 there is a tradeoff between delta-v and transit time. You can get e.g. from L5 to LLO very cheaply (almost as cheap as from L1/L2), but it will take a long time (weeks).

Thanks! Do you think there would be some optimal halo orbit radius for L1/2 that minimizes the delta-v to LLO? Or maybe the optimum would depend on LEO transfer too.

[rklaehn]

I have a trajectory question relating to this - if we wanted to land on the Moon from the Gateway, would there be a delta-v penalty to going to LLO before landing? How much?

Also, is the delta-v from each L-point to the lunar surface similar?

I think there is no penalty for entering LLO. But you don't want to stay in LLO for long because it takes some delta-v to stay in a predefined LLO because of the inhomogenous lunar gravity field.

Regarding the delta-v: L1 and L2 should be roughly similar. With L3, L4 and L5 there is a tradeoff between delta-v and transit time. You can get e.g. from L5 to LLO very cheaply (almost as cheap as from L1/L2), but it will take a long time (weeks).

Thanks! Do you think there would be some optimal halo orbit radius for L1/2 that minimizes the delta-v to LLO? Or maybe the optimum would depend on LEO transfer too.

You can't really answer this without doing a simulation and knowing a lot of details about the proposed station. A larger halo orbit radius should help with getting from EML1/2 to LLO. But if you increase it too much you need more stationkeeping delta-v. On the other hand the stationkeeping could be done using electric propulsion, which would make it cheaper than delta-v that has to be impulsive.

I think that since there is no particular benefit of being precisely at EML1 or 2, you would probably start at, say, EML2 and then increase the halo orbit radius gradually until the stationkeeping cost becomes to high.

You might even move the station to a larger halo orbit for arrival and departure of vehicles from earth or the moon, and move it to a tighter halo orbit for long periods without visiting vehicles.

[Robotbeat]

...I'm not sure about Crew, because transit times might get too long for Crewed Dragon....

Why is that? Crewed Dragon volume (10m^3) is not much less than the combined volume of the Apollo LM (~6m^3) and Apollo Command Module (~6m^3). Heck, the two-person Gemini spacecraft was only barely more than 2m^3 for two astronauts, and it demonstrated a ~14 day mission. 10m^3 for 4 astronauts would be positively roomy by comparison.

That's for cislunar transport, not for other beyond-LEO missions.

EDIT: That applies for CST-100, too, though it might want to add solar arrays and may have a little harder time finding a suitable launch vehicle, though I doubt that's a deal breaker.

[baldusi]

...I'm not sure about Crew, because transit times might get too long for Crewed Dragon....

Why is that? Crewed Dragon volume (10m^3) is not much less than the combined volume of the Apollo LM (~6m^3) and Apollo Command Module (~6m^3). Heck, the two-person Gemini spacecraft was only barely more than 2m^3 for two astronauts, and it demonstrated a ~14 day mission. 10m^3 for 4 astronauts would be positively roomy by comparison.

That's for cislunar transport, not for other beyond-LEO missions.

EDIT: That applies for CST-100, too, though it might want to add solar arrays and may have a little harder time finding a suitable launch vehicle, though I doubt that's a deal breaker.

Once you add the necessary support (ECLSS, potty, etc.) equipment and radiation reduction layers, you start eating your volume. A Lunar Dragon would have less than 10m³. Might be doable, though. But it would definitely be Dragon 3.0 (2.0 being the crewed version). Please note that they will probably move cargo to Dragon 2.0, to test it before putting a crew on it.
That's also why the CST-100 is designed the way it is. Most of the complications of a BEO design would go into a new and improved Service Module and heat shield.
And wrt the LV, they could always man rate the Delta IV Heavy, do an Atlas V Heavy or even better, do an Atlas V Phase 2. Why would NASA pay for such a development when they have the SLS/Orion stack, is beyond me, thou.
I do see them doing Cargo to EML2, and letting the Crewed capsule to EML2 as an exercise to the supplier.

[Robotbeat]

...I'm not sure about Crew, because transit times might get too long for Crewed Dragon....

Why is that? Crewed Dragon volume (10m^3) is not much less than the combined volume of the Apollo LM (~6m^3) and Apollo Command Module (~6m^3). Heck, the two-person Gemini spacecraft was only barely more than 2m^3 for two astronauts, and it demonstrated a ~14 day mission. 10m^3 for 4 astronauts would be positively roomy by comparison.

That's for cislunar transport, not for other beyond-LEO missions.

EDIT: That applies for CST-100, too, though it might want to add solar arrays and may have a little harder time finding a suitable launch vehicle, though I doubt that's a deal breaker.

Once you add the necessary support (ECLSS, potty, etc.) equipment and radiation reduction layers, you start eating your volume. A Lunar Dragon would have less than 10m³. Might be doable, though. But it would definitely be Dragon 3.0 (2.0 being the crewed version). Please note that they will probably move cargo to Dragon 2.0, to test it before putting a crew on it.
That's also why the CST-100 is designed the way it is. Most of the complications of a BEO design would go into a new and improved Service Module and heat shield.
And wrt the LV, they could always man rate the Delta IV Heavy, do an Atlas V Heavy or even better, do an Atlas V Phase 2. Why would NASA pay for such a development when they have the SLS/Orion stack, is beyond me, thou.
I do see them doing Cargo to EML2, and letting the Crewed capsule to EML2 as an exercise to the supplier.

Apollo and Gemini didn't have potties. Soyuz has a small one that would be appropriate for the task. ECLSS can be open-loop for the most part. There's plenty of space in there for a trip lasting a week or two at most.

Suck it up and get on the rocket.

[krytek]

...I'm not sure about Crew, because transit times might get too long for Crewed Dragon....

Why is that? Crewed Dragon volume (10m^3) is not much less than the combined volume of the Apollo LM (~6m^3) and Apollo Command Module (~6m^3). Heck, the two-person Gemini spacecraft was only barely more than 2m^3 for two astronauts, and it demonstrated a ~14 day mission. 10m^3 for 4 astronauts would be positively roomy by comparison.

That's for cislunar transport, not for other beyond-LEO missions.

EDIT: That applies for CST-100, too, though it might want to add solar arrays and may have a little harder time finding a suitable launch vehicle, though I doubt that's a deal breaker.

Once you add the necessary support (ECLSS, potty, etc.) equipment and radiation reduction layers, you start eating your volume. A Lunar Dragon would have less than 10m³. Might be doable, though. But it would definitely be Dragon 3.0 (2.0 being the crewed version). Please note that they will probably move cargo to Dragon 2.0, to test it before putting a crew on it.
That's also why the CST-100 is designed the way it is. Most of the complications of a BEO design would go into a new and improved Service Module and heat shield.
And wrt the LV, they could always man rate the Delta IV Heavy, do an Atlas V Heavy or even better, do an Atlas V Phase 2. Why would NASA pay for such a development when they have the SLS/Orion stack, is beyond me, thou.
I do see them doing Cargo to EML2, and letting the Crewed capsule to EML2 as an exercise to the supplier.

Apollo and Gemini didn't have potties. Soyuz has a small one that would be appropriate for the task. ECLSS can be open-loop for the most part. There's plenty of space in there for a trip lasting a week or two at most.

Suck it up and get on the rocket.

A potty for BEO is a worthwhile compromise. The alternatives may save mass, but I don't think the hassle is worth it.