Starship Artemis Contract & Lunar Starship

[JIS]

But wait, I do not criticise the decision to build minimalistic launch pad first. The problem is they made a promise to launch HLS in 2024 (2025) while doing "minimal" efforts to have necessary infrastructure in place.

Everybody in the space industry and at NASA knew that the 2024 date was a fantasy for a contract award in 2021. SpaceX could either decline to bid at all, or bid and win and then ignore the formal schedule and make their best effort at executing. They chose the latter. Note that SLS, Orion, and the space suits also missed their schedules. Do you think that either of the other two HLS bids would have made the schedule?

Then what is the problem?

I have no problem. You stated that it is a problem.

Apparently, Duffy, et.al. thinks it's a problem that needs to be solved, apparently by using another fantasy architecture that magically works by creating a new alternative and dictating a three-year schedule.

In my opinion SpaceX has a high probability of being ready for Artemis III by the end of 2028.

It seems to be a problem for NASA and congress. Musk and SpaceX seem not to be concerned about Artemis project schedule. They can certainly promise end of 2028 without any consequences and everyone will be happy. Maybe congress should throw in few more billions.     

SLS/Orion will be ready to execute a high-risk Artemis III mission if they succeed with the high-risk Artemis II mission. If these missions fly, I really hope they succeed, or at least that the crews survive. Success is likely, it's just that IMO the probability of failure is unacceptable.

I don't think that Orion mission should be a high risk mission. If anything goes wrong it will be Lunar landing and ascend. I would expect that SpaceX will need several HLS demos to have any chance.

[JIS]

I think the Starship HLS architecture is simpler than the Blue Moon one. Number of launches isn’t architectural complexity but instead number of unique elements.

Architecturally, they're almost identical.  SpaceX uses a tanker, a depot, and an HLS, all based on a common propulsion technology and launcher, with refueling occurring before the crew boards.  Blue uses a tanker (a GS2), a depot (the Cislunar Transporter), and an HLS, all based on a common propulsion technology (BE-7) and launcher, with refueling occurring before the crew boards.

It's fair to argue that ZBO for hydrolox is a lot more complicated than ZBO or near-ZBO for methalox.  But it's equally fair to argue that an architecture that requires 3-5 launches is simpler than one that requires 10-15 launches.

The big difference between SpaceX and Blue is that SpaceX is ahead of Blue by 2-4 years.

Why do you think that SpaceX has 2-4 years lead on Blue Origin? I assume it is in regards to Artemis program. It is hard to see any SpaceX lead at all.

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected.

2. SpaceX launcher upper stage is in the middle of major iteration, lot of work expected to ensure reusability. Blue Origin seem to be pretty much finished with the design of their second stage.

3. SpaceX tanker should be tested in 2026, based on Starship. BO tanker is based on NG second stage, however it is not needed for flags&footprint mission.

4. SpaceX long loiter depot progress is unknown. BO cislunar transporter progress is unknown.

5. SpaceX HLS progress: component testing, based on Dragon. BO HLS: component testing, MK1 demo moon landing in 2026.

[kevinstout]

To me, June 2026 prop transfer feels very ambitious, but given that, the other two dates feel unambitious. Why 15 months between HLS Demo and real HLS?

Prop has to accumlate for these fights. a depot lauch plus 10 tanker launches per test I guess?  Tanker flights and flight rate must be the long poles.  After the prop transfer demo,  probably the next 20 something launches are HLS related.  I believe elon said they  wanted to send something to mars next year too.

[StraumliBlight]

When will the first dedicated Propellent Depot Starship (no heatshield/flaps) be likely to launch, before Q1 2027?

[envy887]

I think the Starship HLS architecture is simpler than the Blue Moon one. Number of launches isn’t architectural complexity but instead number of unique elements.

Architecturally, they're almost identical.  SpaceX uses a tanker, a depot, and an HLS, all based on a common propulsion technology and launcher, with refueling occurring before the crew boards.  Blue uses a tanker (a GS2), a depot (the Cislunar Transporter), and an HLS, all based on a common propulsion technology (BE-7) and launcher, with refueling occurring before the crew boards.

It's fair to argue that ZBO for hydrolox is a lot more complicated than ZBO or near-ZBO for methalox.  But it's equally fair to argue that an architecture that requires 3-5 launches is simpler than one that requires 10-15 launches.

The big difference between SpaceX and Blue is that SpaceX is ahead of Blue by 2-4 years.

Why do you think that SpaceX has 2-4 years lead on Blue Origin? I assume it is in regards to Artemis program. It is hard to see any SpaceX lead at all.

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected.

2. SpaceX launcher upper stage is in the middle of major iteration, lot of work expected to ensure reusability. Blue Origin seem to be pretty much finished with the design of their second stage.

3. SpaceX tanker should be tested in 2026, based on Starship. BO tanker is based on NG second stage, however it is not needed for flags&footprint mission.

4. SpaceX long loiter depot progress is unknown. BO cislunar transporter progress is unknown.

5. SpaceX HLS progress: component testing, based on Dragon. BO HLS: component testing, MK1 demo moon landing in 2026.

What do you mean by "flags and footprints"? A Mk1-based mission, using a crew capsule that hasn't been designed yet and an unspecified number of launches and supporting elements? How can you posit that would be faster than Starship HLS when there are no details available?

[envy887]

To me, June 2026 prop transfer feels very ambitious, but given that, the other two dates feel unambitious. Why 15 months between HLS Demo and real HLS?

Prop has to accumlate for these fights. a depot lauch plus 10 tanker launches per test I guess?  Tanker flights and flight rate must be the long poles.  After the prop transfer demo,  probably the next 20 something launches are HLS related.  I believe elon said they  wanted to send something to mars next year too.

There's a Mars window in Nov/Dec '26, and I could see that being the reason for the HLS Demo being pushed to Q1 '27. I think there's considerably less than 50% chance SpaceX even sends anything in that Mars window, but it sounds like they are still working towards that happening.

[Brigantine]

Definitions of a facility and its buffer are vague. Written law, at least in the western tradition, is never settled until it's tested in the courts and the edges sharpened.

I don't envy the judge that has to decide how far a "nautical mile" is on the moon. Possible values will vary by a factor of 4

[Reynold]

Why do you think that SpaceX has 2-4 years lead on Blue Origin? I assume it is in regards to Artemis program. It is hard to see any SpaceX lead at all.

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected.

2. SpaceX launcher upper stage is in the middle of major iteration, lot of work expected to ensure reusability. Blue Origin seem to be pretty much finished with the design of their second stage.

3. SpaceX tanker should be tested in 2026, based on Starship. BO tanker is based on NG second stage, however it is not needed for flags&footprint mission.

4. SpaceX long loiter depot progress is unknown. BO cislunar transporter progress is unknown.

5. SpaceX HLS progress: component testing, based on Dragon. BO HLS: component testing, MK1 demo moon landing in 2026.

Regarding item 2, while SpaceX is in the middle of a major upgrade of their upper stage, if it doesn't work well, they can fall back on expending it, exactly like BO. 

Regarding item 4, SpaceX does have some experience with cryogenic oxygen in deep space from the Falcon 9 missions that had long wait times between upper stage ignitions, and have done a tank to tank transfer in space.  I would consider a timeline for demonstrating a depot to be lower risk than a timeline for BO to finish building their first ever lander, demonstrate a successful landing, redesign it to be larger and with human transport capability, demonstrate a landing of that, and build the flight model. 

Finally, for item 5, SpaceX has done a lot more than "component testing".  They have flown many manned missions with multiday ECLS capability, done many dockings with the ISS, demonstrated long duration (6+ month) orbital stability of Dragon, have shown hardware for their HLS airlock, elevator, etc. and already done astronaut training with them with NASA.  In addition they have a demonstrated space suit as a backup in case the Axiom one isn't ready.  While BO does seem to have an active ECLS system in their New Shepard capsule, I would be surprised if it has been demonstrated for a full day on the ground, and it certainly hasn't been run for a day in microgravity.  Maybe BO has done other component testing like docking testing that we have not seen and shown it to NASA, but I would think some word would leak out. 

And if you want to give credit to BO for a planned moon landing in 2026, you have to give equal credit to SpaceX for a planned fuel depot demonstration in 2026.  Both have ongoing hardware development going on, they are not just powerpoint presentations. 

While I don't think it will take BO 2-4 years to catch up to where SpaceX is now, I would expect at least a year, and unfortunately for them, SpaceX will not be standing still during that time.  As a general thing I also suspect SpaceX benefits at this point from working very closely with NASA on launcher and human spaceflight issues for years now, so there is probably a lot of trust built up that BO will have to replicate with NASA. 

[Mercurius]

I think the Starship HLS architecture is simpler than the Blue Moon one. Number of launches isn’t architectural complexity but instead number of unique elements.

Architecturally, they're almost identical.  SpaceX uses a tanker, a depot, and an HLS, all based on a common propulsion technology and launcher, with refueling occurring before the crew boards.  Blue uses a tanker (a GS2), a depot (the Cislunar Transporter), and an HLS, all based on a common propulsion technology (BE-7) and launcher, with refueling occurring before the crew boards.

It's fair to argue that ZBO for hydrolox is a lot more complicated than ZBO or near-ZBO for methalox.  But it's equally fair to argue that an architecture that requires 3-5 launches is simpler than one that requires 10-15 launches.

The big difference between SpaceX and Blue is that SpaceX is ahead of Blue by 2-4 years.

Why do you think that SpaceX has 2-4 years lead on Blue Origin? I assume it is in regards to Artemis program. It is hard to see any SpaceX lead at all.

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected.

2. SpaceX launcher upper stage is in the middle of major iteration, lot of work expected to ensure reusability. Blue Origin seem to be pretty much finished with the design of their second stage.

3. SpaceX tanker should be tested in 2026, based on Starship. BO tanker is based on NG second stage, however it is not needed for flags&footprint mission.

4. SpaceX long loiter depot progress is unknown. BO cislunar transporter progress is unknown.

5. SpaceX HLS progress: component testing, based on Dragon. BO HLS: component testing, MK1 demo moon landing in 2026.

Hello,

You answered Within your reply, so question why do you even ask.

Higlighted for you:

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected. + half year

2 first sentence true. Second sentence is not. V3 starship is under development and expected to be ready with the end result in 2026, either in the H1, (no drama) or H2 (with drama). Blue has an upper stage which need to be redesigned, upgraded, developed for the MK1.5, 2, or whatever. It is not even decided what they will do. I understand they can haul a not usable moon lander in 2026, just need to do the next step afterwards so +2 year to settle.

3. As you wrote it will be tested in 2026. Not for Blue. So in the same timeframe which you put in with point 1, this will be rectified on Spacex side. This means it is a task and as a result will cause another point which will take considerable plus effort for Blue to complete too.+ 1 year advantage

4. We can skip, not enough data.
5. BO will have integrated test in 2026. Spacex will have integrated test in 2027 - 1 year

So final calculation is 2,5 year advantage on Spacex side, as you wrote.

[JIS]

I think the Starship HLS architecture is simpler than the Blue Moon one. Number of launches isn’t architectural complexity but instead number of unique elements.

Architecturally, they're almost identical.  SpaceX uses a tanker, a depot, and an HLS, all based on a common propulsion technology and launcher, with refueling occurring before the crew boards.  Blue uses a tanker (a GS2), a depot (the Cislunar Transporter), and an HLS, all based on a common propulsion technology (BE-7) and launcher, with refueling occurring before the crew boards.

It's fair to argue that ZBO for hydrolox is a lot more complicated than ZBO or near-ZBO for methalox.  But it's equally fair to argue that an architecture that requires 3-5 launches is simpler than one that requires 10-15 launches.

The big difference between SpaceX and Blue is that SpaceX is ahead of Blue by 2-4 years.

Why do you think that SpaceX has 2-4 years lead on Blue Origin? I assume it is in regards to Artemis program. It is hard to see any SpaceX lead at all.

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected.

2. SpaceX launcher upper stage is in the middle of major iteration, lot of work expected to ensure reusability. Blue Origin seem to be pretty much finished with the design of their second stage.

3. SpaceX tanker should be tested in 2026, based on Starship. BO tanker is based on NG second stage, however it is not needed for flags&footprint mission.

4. SpaceX long loiter depot progress is unknown. BO cislunar transporter progress is unknown.

5. SpaceX HLS progress: component testing, based on Dragon. BO HLS: component testing, MK1 demo moon landing in 2026.

Hello,

You answered Within your reply, so question why do you even ask.

Higlighted for you:

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected. + half year

2 first sentence true. Second sentence is not. V3 starship is under development and expected to be ready with the end result in 2026, either in the H1, (no drama) or H2 (with drama). Blue has an upper stage which need to be redesigned, upgraded, developed for the MK1.5, 2, or whatever. It is not even decided what they will do. I understand they can haul a not usable moon lander in 2026, just need to do the next step afterwards so +2 year to settle.

3. As you wrote it will be tested in 2026. Not for Blue. So in the same timeframe which you put in with point 1, this will be rectified on Spacex side. This means it is a task and as a result will cause another point which will take considerable plus effort for Blue to complete too.+ 1 year advantage

4. We can skip, not enough data.
5. BO will have integrated test in 2026. Spacex will have integrated test in 2027 - 1 year

So final calculation is 2,5 year advantage on Spacex side, as you wrote.

I can't really see how anyone can claim SpaceX has any schedule advantage for Artemis 3 at all.

BO just proved their launcher is ready. Their MK1 tug/lander should have the first lunar landing in 2016 and they can upgrade it if needed. I expect BO to team up with LM to provide Orion derived crew cabin. What is missing is the ascend stage but I don't think this needs to be a clean sheet or that any new tech is needed. This will be a decisive factor.

SpaceX schedulewise is in much worse position. Their launcher is not ready. Moreover they seem to insist on rapid reusability as a precondition for the Artemis mission. They also need refueling in mass scale. They can't perform any lunar mission at all without refueling. When this can happen no one knows for sure and it needs loads of new technology.

Obviously, it is questionable whether congress would be willing to relax requirements for BO sustainable architecture (Artemis V) and put more money to speed up BO HLS ascend stage and crew cabin. Me personally I think not and they will just let BO and SpaceX to go with their own internal schedules. It means that BO will be bogged down with LHX refueling. I don't believe they will be able to sort out cislunar transporter and refueling before 2030.   

   
 

[envy887]

I expect BO to team up with LM to provide Orion derived crew cabin. What is missing is the ascend stage but I don't think this needs to be a clean sheet or that any new tech is needed. This will be a decisive factor.

An Orion-derived crew cabin with unspecified propulsion from the lunar surface to NRHO is a WHOLE NEW SPACECRAFT. A whole new crew spacecraft with NASA crew rating and the required uncrewed demo mission is absolutely not happening before the end of 2028. It just isn't. Nobody has ever built a whole new crew spacecraft that fast, and Blue certainly isn't going to be the first.

The only way crewed Mk1 happens is if Blue integrates the crew compartment atop the cargo lander and the whole thing goes to the surface and back. But that requires either refueling or multiple Transporters to close the delta-v budget. Mk1 would provide all services needed: GNC, comms, RCS, propulsion, thermal, power, etc.

SpaceX schedule wise is in much worse position. Their launcher is not ready.

New Glenn is also not ready. It's done 2 launches, at a cadence far too slow for any sort of crewed lunar mission. I'll accept that it might be ready in 2028, but there's no particular reason to believe that New Glenn will be ready and Starship (which has launched 11 times) will not be ready.

Moreover they seem to insist on rapid reusability as a precondition for the Artemis mission.

Not really. SpaceX has already demonstrated the necessary booster reuse. They can use expendable tankers, or at least build enough that they are not restricted by ship reuse cadence for any particular mission. Ship reuse is something they are pushing for, but not necessarily something they need to perfect by 2028.

They also need refueling in mass scale. They can't perform any lunar mission at all without refueling.

Blue hasn't published a reference mission without refueling. Mk1 definitely can't do it by itself with no refueling, but how they plan to get the additional performance necessary is as yet unspecified. So it's not actually clear that Blue is offering any improvement on that. Their baseline Mk2 mission has lots of refueling.

[OTV Booster]

In SpaceX's case tanker/depot/HLS are all variant of the launch vehicle upper stage, I don't think that's the case for Blue Origin. Blue's tanker share tankage with their LV upper stage, but use a different engine, I don't think the Transporter and Mk2 lander is a variant of GS2. Thus it's correct to say Blue Moon has more unique elements and more complex.

I suspect that Blue is all-in on this alternate plan.  I expect the CT and BM1.5 thrust structures to be very close to identical, and of course the engines are identical.  Since they've started floating the idea of BM1s and a BM1.5 as a conops, I assume that CT is now based on BM1 inside the fairing, and CT and BM1.5's tankage will be close to common.

As for conops, Starship only does refueling in Earth orbit, Blue Moon requires additional refueling in NRHO, that's also more complex.

If we're sticking with Orion in NRHO, then Starship needs somewhat higher energy to refuel than VLEO, and even then, the margins are very tight.  If that FCC technical annex is correct, they're planning on a refueling in an HEEO final tanking orbit, which almost certainly means they're refueling twice, the first one being in VLEO.¹

That said, SpaceX is gonna go first unless something really untoward happens.  But there's a reason that Blue's second crack at HLS was so much better than their first:  they drank the refueling Kool-Aid, and it was tasty.

_________
¹The HLS can probably launch directly into a decent-sized HEEO, but there's an odd property to doing that:  If the HLS is almost completely empty, then the depot that serves it, even if it's had the domes re-jiggered to carry as much prop as possible, can't deliver a full tank of prop to the HLS in an HEEO that's high enough to make its margins a non-issue.  You can do better if you dispose of the depot, but even then it's nothing to write home about.

Does it make sense for a depot to stay at HEEO and be serviced by transfer tankers coming up from VLEO? Transfer tankers would top off from a VLEO depot before the trip saving the mass of depot kit. A dedicated TT (Transfer Tanker) would stay on orbit and do away with fins and tiles. It'd be half tanker, half depot, and the lightest of the family. Nothing new to design.


Could one of these make it to VLEO with a reduced engine count? No payload and almost out of propellant. Maybe three vac and one SL.


It makes little sense for one mission every year or two, but looking ahead...


BTW, do to popular demand I have been exerting myself and spelling Artemus as 'Artemis' for weeks now and not even a thankyou.    I am cut. 


Now if I could get you to have mercy with the acronyms...

[DanClemmensen]

Does it make sense for a depot to stay at HEEO and be serviced by transfer tankers coming up from VLEO? Transfer tankers would top off from a VLEO depot before the trip saving the mass of depot kit. A dedicated TT (Transfer Tanker) would stay on orbit and do away with fins and tiles. It'd be half tanker, half depot, and the lightest of the family. Nothing new to design.

Makes sense only if Depot's transfer hardware is very heavy. Otherwise, just use Depot and save the extra two propellant transfers.

[OTV Booster]

Why do you think that SpaceX has 2-4 years lead on Blue Origin? I assume it is in regards to Artemis program. It is hard to see any SpaceX lead at all.

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected.

2. SpaceX launcher upper stage is in the middle of major iteration, lot of work expected to ensure reusability. Blue Origin seem to be pretty much finished with the design of their second stage.

3. SpaceX tanker should be tested in 2026, based on Starship. BO tanker is based on NG second stage, however it is not needed for flags&footprint mission.

4. SpaceX long loiter depot progress is unknown. BO cislunar transporter progress is unknown.

5. SpaceX HLS progress: component testing, based on Dragon. BO HLS: component testing, MK1 demo moon landing in 2026.

Regarding item 2, while SpaceX is in the middle of a major upgrade of their upper stage, if it doesn't work well, they can fall back on expending it, exactly like BO. 

Regarding item 4, SpaceX does have some experience with cryogenic oxygen in deep space from the Falcon 9 missions that had long wait times between upper stage ignitions, and have done a tank to tank transfer in space.  I would consider a timeline for demonstrating a depot to be lower risk than a timeline for BO to finish building their first ever lander, demonstrate a successful landing, redesign it to be larger and with human transport capability, demonstrate a landing of that, and build the flight model. 

Finally, for item 5, SpaceX has done a lot more than "component testing".  They have flown many manned missions with multiday ECLS capability, done many dockings with the ISS, demonstrated long duration (6+ month) orbital stability of Dragon, have shown hardware for their HLS airlock, elevator, etc. and already done astronaut training with them with NASA.  In addition they have a demonstrated space suit as a backup in case the Axiom one isn't ready.  While BO does seem to have an active ECLS system in their New Shepard capsule, I would be surprised if it has been demonstrated for a full day on the ground, and it certainly hasn't been run for a day in microgravity.  Maybe BO has done other component testing like docking testing that we have not seen and shown it to NASA, but I would think some word would leak out. 

And if you want to give credit to BO for a planned moon landing in 2026, you have to give equal credit to SpaceX for a planned fuel depot demonstration in 2026.  Both have ongoing hardware development going on, they are not just powerpoint presentations. 

While I don't think it will take BO 2-4 years to catch up to where SpaceX is now, I would expect at least a year, and unfortunately for them, SpaceX will not be standing still during that time.  As a general thing I also suspect SpaceX benefits at this point from working very closely with NASA on launcher and human spaceflight issues for years now, so there is probably a lot of trust built up that BO will have to replicate with NASA.

While I generally disagree with JIS on this topic (peace bro), ISTM your analysis on point 4 is unfair.


Falcon9 second stage is aluminum (something)grid. A thick slab of aluminum hogged out to leave a rectangular grid of ribs. This so so different from SS's thin stainless plate that extrapolation isn't much more than guesswork. My guess is the engineers can't wait to get their hands on real data so they refine their models and decide who owes who a beer.


And BO has been landing New Sheppard for years now. IMO earth and lunar landing are more similar than F9 and SS boiloff.

[envy887]

Falcon 9 second stage is aluminum (something)grid. A thick slab of aluminum hogged out to leave a rectangular grid of ribs. This so so different from SS's thin stainless plate that extrapolation isn't much more than guesswork.

Falcon loiter times on direct GEO missions are about 6 to 8 hours. Both stages of Falcon use skin and stringer construction, much like Starship. Orthogrid or isogrid would not be much different in thermal terms anyway. It's a data point for the models, but hardly a prototype. And the models should already be pretty good, thermal modeling for these sorts of problems is quite advanced.

[OTV Booster]

I think the Starship HLS architecture is simpler than the Blue Moon one. Number of launches isn’t architectural complexity but instead number of unique elements.

Architecturally, they're almost identical.  SpaceX uses a tanker, a depot, and an HLS, all based on a common propulsion technology and launcher, with refueling occurring before the crew boards.  Blue uses a tanker (a GS2), a depot (the Cislunar Transporter), and an HLS, all based on a common propulsion technology (BE-7) and launcher, with refueling occurring before the crew boards.

It's fair to argue that ZBO for hydrolox is a lot more complicated than ZBO or near-ZBO for methalox.  But it's equally fair to argue that an architecture that requires 3-5 launches is simpler than one that requires 10-15 launches.

The big difference between SpaceX and Blue is that SpaceX is ahead of Blue by 2-4 years.

Why do you think that SpaceX has 2-4 years lead on Blue Origin? I assume it is in regards to Artemis program. It is hard to see any SpaceX lead at all.

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected.

2. SpaceX launcher upper stage is in the middle of major iteration, lot of work expected to ensure reusability. Blue Origin seem to be pretty much finished with the design of their second stage.

3. SpaceX tanker should be tested in 2026, based on Starship. BO tanker is based on NG second stage, however it is not needed for flags&footprint mission.

4. SpaceX long loiter depot progress is unknown. BO cislunar transporter progress is unknown.

5. SpaceX HLS progress: component testing, based on Dragon. BO HLS: component testing, MK1 demo moon landing in 2026.

Hello,

You answered Within your reply, so question why do you even ask.

Higlighted for you:

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected. + half year

2 first sentence true. Second sentence is not. V3 starship is under development and expected to be ready with the end result in 2026, either in the H1, (no drama) or H2 (with drama). Blue has an upper stage which need to be redesigned, upgraded, developed for the MK1.5, 2, or whatever. It is not even decided what they will do. I understand they can haul a not usable moon lander in 2026, just need to do the next step afterwards so +2 year to settle.

3. As you wrote it will be tested in 2026. Not for Blue. So in the same timeframe which you put in with point 1, this will be rectified on Spacex side. This means it is a task and as a result will cause another point which will take considerable plus effort for Blue to complete too.+ 1 year advantage

4. We can skip, not enough data.
5. BO will have integrated test in 2026. Spacex will have integrated test in 2027 - 1 year

So final calculation is 2,5 year advantage on Spacex side, as you wrote.

I can't really see how anyone can claim SpaceX has any schedule advantage for Artemis 3 at all.

BO just proved their launcher is ready. Their MK1 tug/lander should have the first lunar landing in 2016 and they can upgrade it if needed. I expect BO to team up with LM to provide Orion derived crew cabin. What is missing is the ascend stage but I don't think this needs to be a clean sheet or that any new tech is needed. This will be a decisive factor.

SpaceX schedulewise is in much worse position. Their launcher is not ready. Moreover they seem to insist on rapid reusability as a precondition for the Artemis mission. They also need refueling in mass scale. They can't perform any lunar mission at all without refueling. When this can happen no one knows for sure and it needs loads of new technology.

Obviously, it is questionable whether congress would be willing to relax requirements for BO sustainable architecture (Artemis V) and put more money to speed up BO HLS ascend stage and crew cabin. Me personally I think not and they will just let BO and SpaceX to go with their own internal schedules. It means that BO will be bogged down with LHX refueling. I don't believe they will be able to sort out cislunar transporter and refueling before 2030.   

   

SX aspires to have rapid reusability. We have no evidence that they will allow this aspiration to get in the way of the Artemis mission. We admittedly also have no evidence of the opposite. IMO SX will go with what they have.


It looks as if they will be able get the ship back in mostly one piece but that says nothing about reusability, rapid or not. Worst case the tanker is toast. Next worst, the whole heatshield needs to be replaced and early iterations take a month or more for a recycle. Let's assume the worst and figure the first operational refueling campaign will not be able to reuse any tankers.


Using your figure of 10 tanker flights that means ten tankers and 10 heatshield tests. Maybe half can eventually be reused with better heatshields. Maybe the survivors will be worth hanging onto for future use. Maybe not. Again, staying with a worst case, even the tankers that get scrapped will yield up usable engines.


You're really negative on SX performance on Artemis. They're not perfect and yes, they do stick with the Starship architecture. That's why they were able to submit the lowest bid. Nobody, from SpaceX to NASA, to congress, to us NSF'ers, expected things to stay on schedule. Very few programs in this industry stay within budget or on time. To hit even one is a major accomplishment.


To suddenly start complaining (not you, the dimwits in government) that SX is holding things up is to ignore both the realities of hardware development and traditional aspirational role of timelines in these contracts. It's called 'moving the goalpost'.

[OTV Booster]

Does it make sense for a depot to stay at HEEO and be serviced by transfer tankers coming up from VLEO? Transfer tankers would top off from a VLEO depot before the trip saving the mass of depot kit. A dedicated TT (Transfer Tanker) would stay on orbit and do away with fins and tiles. It'd be half tanker, half depot, and the lightest of the family. Nothing new to design.

Makes sense only if Depot's transfer hardware is very heavy. Otherwise, just use Depot and save the extra two propellant transfers.

Transfer hardware, propellant cooling w/solar panels & radiators, maybe a sunshield. A full set of 6 or 9 engines and maybe CMGs for thrustless attitude control.


Mate with the VLEO depot, transfer propellant and stay hooked up until time to raise orbit. Recirculate propellant through the depot to maintain chill. Big question is how long and how much boiloff getting from VLEO to the HEEO depot.

[OTV Booster]

Falcon 9 second stage is aluminum (something)grid. A thick slab of aluminum hogged out to leave a rectangular grid of ribs. This so so different from SS's thin stainless plate that extrapolation isn't much more than guesswork.

Falcon loiter times on direct GEO missions are about 6 to 8 hours. Both stages of Falcon use skin and stringer construction, much like Starship. Orthogrid or isogrid would not be much different in thermal terms anyway. It's a data point for the models, but hardly a prototype. And the models should already be pretty good, thermal modeling for these sorts of problems is quite advanced.

I could swear I saw an inside tank pic showing what looked kind a hogged out grid. I used to remember thing but can't remember how long ago that was.

[TheRadicalModerate]

Why do you think that SpaceX has 2-4 years lead on Blue Origin? I assume it is in regards to Artemis program. It is hard to see any SpaceX lead at all.

1. SpaceX reused booster of their launcher but is in the middle of major upgrade. BO recovered their booster with no major design changes expected.

You don't think there's going to be a major upgrade with New Glenn sometime in the next couple of years?  Why?

It seems a lot of the upgrades that SpaceX is pursing are performance-based.  Blue hasn't gotten to that point yet, but it's highly unlikely that they're going to hit the 45t to LEO metric without a fair amount of fiddling.

BTW:  They really need the 45t to LEO.  Without it, my guess is that the accelerated plan they're proposing to NASA won't work. 

2. SpaceX launcher upper stage is in the middle of major iteration, lot of work expected to ensure reusability. Blue Origin seem to be pretty much finished with the design of their second stage.

I agree that this is a risk for SpaceX.  However, the advantages of a high-cadence prop aggregation campaign over a lower-cadence one are pretty compelling.  These people aren't idiots; somebody's made the judgment that reusability, then refueling, is a faster path to the Option A demo than the other way around.

3. SpaceX tanker should be tested in 2026, based on Starship. BO tanker is based on NG second stage, however it is not needed for flags&footprint mission.

The tanker isn't the critical path; the Cislunar Transporter is.  I suspect that Blue's accelerated schedule will take the CT's docking, prop transfer, and prop storage hardware from the plan-of-record CT and move it onto a BM1-based set of tankage, which will be launchable inside the fairing, instead of being stacked, as CT was to be.  But both vehicles still need a BE-7-based thrust structure.

FWIW, I think Blue is being very smart pushing BM1 testing to the head of the queue.  It's on the critical path for both the BM1-based CT and the BM1.5 (assuming they go this route).  I expect the thrust structure to be largely common between the two vehicles.

One other thing to keep in mind:  Blue has zero experience with on-orbit RPODs.  Getting experience requires one of the following two milestones:
- High-cadence operations.  SpaceX is way out ahead of Blue on this.
- Orbital hardware with long lifetime.  Neither company has this demonstrated, but my guess is that SpaceX is a couple of years ahead on this.  Blue, after all, needs a vehicle that can service paying customers, and needs to prioritize the testing that gets them there.  SpaceX already has one of those.

4. SpaceX long loiter depot progress is unknown. BO cislunar transporter progress is unknown.

This is a complicated question, but it can be simplified by dividing it into two different environments:  LEO and cislunar.  LEO is much more difficult.  Its difficulty can be reduced by spending as little time there as possible.  That's a function of launch cadence, which is, I suspect, the reason that SpaceX has prioritized reusability over tanking experiments.

Compared to LEO, cislunar boiloff management is a lot easier, because you can point the nose at the Sun and dramatically reduce insolation on the tankage.  However, it's even easier if you're managing methalox instead of hydrolox.

5. SpaceX HLS progress: component testing, based on Dragon. BO HLS: component testing, MK1 demo moon landing in 2026.

What makes you think they're not testing components in the current Starship test campaigns?  Just because some components are coming from D2 (a source that Blue doesn't have available to them) doesn't mean they're not doing integration tests on the missions.

[Paul451]

Falcon 9 second stage is aluminum (something)grid. A thick slab of aluminum hogged out to leave a rectangular grid of ribs.

Both stages of Falcon use skin and stringer construction, much like Starship.

I could swear I saw an inside tank pic showing what looked kind a hogged out grid. I used to remember thing but can't remember how long ago that was.

https://forum.nasaspaceflight.com/index.php?topic=30981.msg1586339#msg1586339

Looks like stringers and skin to me.