jadebenn

I've actually seen the pictures: He is overblowing it. Damage is worse than expected but not structural and not expected to be a major hurdle. There will need to be some fact-finding and mitigation to understand why certain things didn't work as they should, but unless something currently unknown pops up during repairs, it's not a big deal. I'd especially disagree with it being "multiples of Ares I-X," unless that multiple is one. It's about in the same ballpark.

Those are programmatic minimums. In that same thread on NSF, someone dug up the ESD requirements, which, while incomplete, paint a much different picture. https://ntrs.nasa.gov/api/citations/20200001592/downloads/20200001592.pdf

Uh, no? ML-2's entered fabrication. Congress put EUS language in their funding bill for the third time (over the administration's objections), which also directs NASA to prioritize EUS for the 2024 period. EUS CDR will happen sometime soon, and pre-production activities have already started. I know it's old, but that's for Block 1B. The LVSA (the Block 1 equivalent) has been done for a while.

Uh, you could fit a lander in the CPL available on SLS. It just wouldn't be one capable of meeting the much higher requirements for Artemis. NASA isn't interested in doing Lunar surface stays of less than a week. They've requested a design that can get them 2 crew for 7 days (more than 2x the longest Apollo stay) out of the box, and can go to 4 crew for 30 days with a small surface hab to take strain off the lander ECLSS. That means mass. Lots of it.

They're not afraid of hypergols, there's just not a whole lot of good hypergol engines currently available for a lander, and it makes it harder to do an eventual transition to ISRU.

More like a few days. As long as you can get the timing below ~90 days (possible with SLS), there are some pretty high TRL technologies (especially with methane) you can use to mitigate this. From what I'm hearing from my friends on the other side, the two-stage SLS-launched design is actually the best shot at getting at a non-storable lander. The three-stage alternative uses long ballistic transfers for each element due to the mass constraints, which means passive boiloff mitigation (the high TRL stuff) is not gonna cut it. So then you're talking about putting active in-space cryocoolers (low TRL, high power consumption) in an already extremely mass-constrained environment, and suddenly, just using some hypergols seems a lot more practical.

You guys do realize what this news implies about the selection of the HLS lander, right?

The PPE could almost certainly handle moving HALO to TLI, assuming there's no issues with the really long burns required.

Well, it doesn't look like we're getting Lunar Cygnus after all. Spaceflight Now's article has some more deets on the contract award, and it looks like SpaceX is slated to be the only provider.

Indeed, and I very much expect they will. That looks like a heck of a lot more than "a few tweaks."

In other news: Study recommends minimizing elements for Artemis lunar lander The study in question was actually posted on /r/SpaceLaunchSystem a few months back. Very hard to link directly, though. The site it's on doesn't like you doing that. Aerojet's top pick was a bit different from Boeing's current proposal in that it farms out the ascent module to a CLV and uses the SLS Block 1B solely for the descent module. In other words, it's even more gigantic than the modern Boeing proposal - essentially on-par with Altair in scale. Fairly similar to a 2018 Boeing lander proposal, though, which is unfortunately paywalled. The 2018 design proposal had a crew capacity of 4 and a surface stay of 14 days (so essentially 9 Apollo 17s worth of exploration per-mission). From what I've heard, the modern design has a crew capacity of 3 and a surface stay of 7 days (so only about 3 Apollo 17s worth by comparison), likely due to the downgrade required to fit within the payload limits of early Block 1B instead of late Block 1B/Block 2. The modern proposal definitely seems to come from the same design lineage as the 2018 proposal, however. There's quite a bit of visual resemblance between them. Render of the 2018 proposal:

I'll take you on. Not that I think there's any way we can verify it with how secretive SpaceX is with their financials, though.

NASA has decided to use the LH2 and LOX tanks that were originally fabricated for the first core stage (and subsequently sidelined due to welding issues) in the construction of the third core stage. NASA believes they can repair the welds to make the tanks safe for flight (likely aided by the data gleaned from the testing of the LH2 and LOX STAs). Image source If you want some speculation from yours truly: This is probably being done in order to cram another SLS flight into the manifest prior to 2024. That way they can move straight on to fabricating the tanks for CS-4. If NASA ends up going with an integrated SLS-launched lander after all, they'll probably launch it off the CS-3 core that uses these tanks.

Let me kick up some salt:

10 tons is significant. It's toughly equivalent to the capacity of an expendable FH launch when you factor in that Orion means you don't need to budget mass for a tug in the CPL. I wouldn't bet on this. Remember, Doug Loverro is reviewing the Artemis architecture, and is projected to release the results of his deep dive in mid-March. We might be seeing some changes...