jadebenn

Found a recent report on the development of the Z-2, and decided to make this thread to discuss it. Right now, they're working on a demonstration prototype they're calling the Z-2.5, which, for budgetary reasons, utilizes the existing EMU bottoms and arms. This demonstration article is supposed to fly to the ISS in 2023 for testing, and the data would be used in the final, full version of the suit. However, with Artemis wanting a Moon landing in 2024, this schedule will likely need to be accelerated. Especially because I'm fairly certain that old shuttle EMU leggings will not be up to the task of walking on the lunar surface. I seriously recommend skimming through the linked report. It's an interesting read; lots of neat technical data and engineering stuff.

Just comes from the person I talk to at MSFC.

Bit of both? The old EUS was only delayed because NASA getting appropriations for ML-2 placed it outside of the critical path, so resources were redirected to more pressing needs, such as the core stage. They've been using the extra time to optimize the EUS's design for maximum mass to TLI, so there's been some design changes.

Artemis 3 confirmed to be on SLS Block 1B.

Ah, okay. Yeah, that's reasonable. There's more margin than you think, though. Even if a failure were to happen in 2021, you could "steal" the SLS for Europa Clipper, or perhaps even order a new one if there's enough slack in the production line. The biggest difficulty would be getting an Orion ready in-time for Artemis 4 (which would be the new Moon landing mission instead of Artemis 3 if such a failure were to occur). I don't know enough about the timeline for procurement and production of Orion spacecraft to say for-certain whether or not you'd be able to get one put together in-time in such a scenario, though.

It counts for a lot of the manufacturing, transportation, and ground support infrastructure. Allowed some of it to be carried over from the STS program, such as the Pegasus barge (which, admittedly, still had to undergo some pretty major refurbishment). I doubt this, but, well, I tend to disagree with a lot of people's predictions about the trajectory of spaceflight in the future anyway, even disregarding stuff like Starship. IMO, the real test of the longevity of the commercial launch providers will be the next recession. I'm certain they'll stick around (as I'm fairly certain the US government would intervene if it looked like they had a chance of failing), but that could spell an end to much of their higher aspirations beyond their currently-existing systems. Probably off-topic to discuss this any further, though. Ah, the ESAS report. You know, this is the report that spawned Constellation, and all the good and bad that came out of that. Real-talk: One of the things that frustrates me most is how few people seem to remember that whole deal. I wasn't even into spaceflight when all that was going down, but I've at least done my homework on it! To me, the biggest lessons of Constellation are twofold: Consistency is the most important thing in HSF A bad part of a decent plan can bring the whole thing down. I have to roll my eyes when some people try and act like Ares I had a smoother development history than SLS. It didn't. It really, really, didn't. I guess I should be happy those people cared enough to look into Constellation at all, but they invariably only know enough to be dangerous. Ares I, as flawed as it was, would almost certainly be flying people to the ISS right now, yet Ares I's flaws are precisely the reason the whole program fell apart. It's a balancing act, I guess.

Not nothing, but yeah, I get your sentiment. There is very little shared apart from some of the guts in the MPS, the RS-25 engines, and the tank diameter. The core stage is closer to being an entirely new rocket than it is to the old Shuttle ET. I would say that the engines are basically unchanged though. The SSMEs were always capable of those thrust levels, they just weren't used because testing revealed they wore out the engines really fast, and NASA really didn't want to take any risks with things on the orbiter post-Challenger. Since these RS-25s will not be recovered and the SLS has an LES, neither of those things are an issue. Cross your fingers!

Artemis 2 was originally going to reuse the avionics and some parts from the capsule flown on Artemis 1, but to avoid schedule impacts, the two have now been completely decoupled. Artemis 2 will now use all-original parts to avoid any potential delays caused by Artemis 1. Also: Green run confirmed to be happening. I believe that to be the right decision, but it's one that almost certainly puts the final nail in the coffin for a 2020 launch. This is probably why Bridenstine was saying 2021 in that one hearing.

Sorry, I misread. To play devil's advocate regarding the "complete" Orion remark: for whatever reason they've actually removed parts that were previously outfitted to it. The Orion undergoing acoustic testing had all its tiles, for example, and the ESM had its solar panels until a few days ago. Maybe some problems came up, or maybe the parts are undergoing seperate testing, but they did used to be attached.

I was talking about the core stage.

It is not. I wish it was, but it is not. They're aiming to have it complete by December.

No. They're still working on it. I don't really understand what you mean with the last part, but as for the first part, well... it's a long story. Ready for the abbreviated version? Okay. Ares 1 rocket. Upper stage SSME. This won't work. Change design. Upper stage J-2X. Now Ares 1 too weak. Orion needs less mass. Take from capsule. Ares 1 still too weak. Orion needs less mass. Take from service module. Ares 1 cancelled. Orion moved to SLS. Design stays same. President doesn't like Moon. NASA doesn't change service module. Election. New president likes Moon. Too late to change service module. Work around it. That's the really compressed version of it.

Found a great picture of the SLS core stage in this article.

Cygnus, actually. Antares is the rocket. It's called the Minimal Habitation Module, which I believe is simply the new name for the US utilization module. It's essentially an over-glorified docking node with life support capability. Sole-sourcing the module was justified by NASA on the basis of schedule (NASA said bidding it out would add 12-18 months of delay). NGIS got the win because they had already done a lot of work on this concept, and had drawn-up detailed plans on how they could build it with existing parts and tooling.

It's something that's theoretically possible, but would require a lot of design work to be made viable. So it almost certainly won't be done.

It can't do it in one launch, but that's not really required, is it? What is required is getting people to cislunar space to begin with, which is something only a rocket as powerful as the SLS can do.

Block 1 SLS core has to do a lot of maneuvering to avoid going into orbit, actually. SLS could easily be a two-stage to orbit design, which should be unsurprising when you consider what it's derived from. The RS-25s, however, cannot be relit once they're extinguished. That was a major hangup during the design of Ares I, and was what ultimately caused the ill-fated switch to J-2X.

This discussion is outside the scope of this thread.

I don't understand your argument. The Saturn V didn't bring people directly to the lunar surface either. It brought the equipment and people to TLI, whereupon the CSM brought the LM and itself into LLO, and the LM brought people to the surface. The only difference from SLS is that the lander didn't launch separately. Neither the Saturn V or SLS have brought or will bring people to the lunar surface by themselves, but each performs the vitally important task of getting a crewed spacecraft near the Moon in the first place. Can't have a human landing without the humans, after all. I don't get your last statement. Block 2 isn't useless from a planning standpoint, it's just not relevant to the near-term. Just to clarify: It's not an option now, but it is an option for the future, one that's built into the spec. The SLS is actually meant to have a fairly minimal on-pad presence. In fact, it can only sit on the pad for 7 days before some of the batteries in it go dead, and a rollback is required. Problem is that you'd need to "stockpile" them (i.e. hold one until the other's complete), and the VAB and ML aren't currently configured for that. It would only really come into play with a Mars campaign, not a lunar one, and without the second ML, it's just not possible to stack SLSes simultaneously. So, yeah, limited to a 6-month launch cadence until ~2024, when ML-2 comes online.

By being the vehicle that can get humans to cislunar space. The Apollo CSM didn't get humans to the surface all by itself, but it was an integral part of the Apollo missions. The only difference is that with the SLS the CSM and LM equivalents will launch separately. There are only two other vehicles in-development that claim to be able to do what SLS+Orion can do. One is the Russian's Federation spacecraft, which has been delayed constantly for lack of funding. The other is SpaceX's Starship, which is in a preliminary design phase, and is insanely technically ambitious. You are also incorrect about what Block 2 is. Block 2 is not a name for a cargo version of SLS - any Block of SLS can be used in a cargo configuration, even Block 1 (as-is the plan for Europa Clipper). Block 2 is simply the name for the SLS variant after the Block 1B SRBs are replaced with the Advanced Boosters - something not likely to happen until a hypothetical Mars campaign. If an extra cargo SLS is needed for a lander, there are actually four SLSes currently in the pipeline. Three are for Artemis. One is for Europa Clipper. You could just bump it off to a commercial launcher and use that extra cargo SLS if necessary.

Some very interesting news here: NASA outlines plans for lunar lander development through commercial partnerships. In particular, I think this quote is quite telling: I am very confident that said "unidentified company" was Blue Origin. They're the only ones I know of who have plans to offer lunar landing craft commercially. There's also some clarification involving design requirements. For one, the lander for the "demonstration mission" must be able to support a surface stay of six-and-a-half days. For reference, the longest Apollo stay was only a little over three. It's also stated that NASA considers an initial expendable design A-okay for the 2024 "demonstration mission," but that landers for later missions must be at least partially reusable. IMO, as someone who's not a Blue Origin fanboy: this contract is theirs to lose. They have a significant head-start over the competition, something that will serve them well in a program with such a time-oriented goal.

Technically its name is 'the Moon' (with a capital 'm') as it's the original one we knew about. 'Luna' is just an alternative name, just like 'Earth' can also be called 'Terra,' or 'the Sun' (with a capital 's') can also be called 'Sol.' I often forget to capitalize it though, as it's easy to forget when when you're talking about our specific Moon versus moons in general.

He must be having a fun time with the surprise inclusion of funding for an NTR prototype in the latest NASA budget bill! IMO, the obsession with moving away from words like 'manned' is silly and unnecessary, but I don't really care all that much, and it's not worth starting fights over. I typically just use whatever term I heard last or is more common. So I usually call them 'man-rated' rockets, but I often alternate between using 'crewed' and 'manned.'

I chat with someone who works at MSFC on another website, and he's said that in the wake of Gerst's reassignment, all of the HEOMD projects are getting their schedules re-baselined. So I don't find a slip to 2021 all that unbelievable, as I'd imagine you'd want a schedule estimate you don't constantly have to preface with, "Well, if everything goes perfectly..." Now, I haven't heard anything to this effect yet, but I wouldn't be surprised. It's the late 2021 estimate that doesn't gel with me. As far as I can tell, that's entirely of Berger's creation.

You've stated that you believe it's late 2021 at best, though, which is something that I feel is wholy unsupported by anything he's been saying.