As far as I can tell its 2 or 3 stage only. 3 stage is the reference but a 2 stage system is allowable, with abort to orbit capabilities being the driving requirement.
I do not see anything in the contract language precluding a 1 stage offering - as you are permitted to have other elements (that do not dock or interact with gateway) supporting your bid in near orbits.
a single-stage lander is unlikely for technical reasons anyway.
Quote from: Proponent on 08/16/2019 01:46 pma single-stage lander is unlikely for technical reasons anyway.Why would you say that? The total delta v for a round trip from LLO to surface and back is <4 km/sec. Plus, to keep things sustainable--i.e., affordable--don't we want the landers to be fully reusable? (Also, from an environmental ethics viewpoint, leaving crashed stages scattered all over the Moon isn't the best idea and arguably a violation of OST--"Leave no trace" should be the guiding principle tbqh.)
Quote from: Proponent on 08/16/2019 01:46 pma single-stage lander is unlikely for technical reasons anyway.Why would you say that? The total delta v for a round trip from LLO to surface and back is <4 km/sec. Plus, to keep things sustainable--i.e., affordable--don't we want the landers to be fully reusable?
Quote from: Warren Platts on 08/16/2019 02:22 pmQuote from: Proponent on 08/16/2019 01:46 pma single-stage lander is unlikely for technical reasons anyway.Why would you say that? The total delta v for a round trip from LLO to surface and back is <4 km/sec. Plus, to keep things sustainable--i.e., affordable--don't we want the landers to be fully reusable? (Also, from an environmental ethics viewpoint, leaving crashed stages scattered all over the Moon isn't the best idea and arguably a violation of OST--"Leave no trace" should be the guiding principle tbqh.)NASA would have to get the lander to LLO and resupply it will propellant. Each refuelling may require more than one launch. This is doable but will probably take more than 5 years.
Why not just dust off the old DC-X design?
Just for the record, this happened exactly like Eric Berger predicted: Marshall selected to lead NASA human lunar lander program
However, several members of Congress from Texas, in an Aug. 15 letter to Bridenstine, objected to those plans, first reported Aug. 13 by Ars Technica. They argued that, given its history in managing human spaceflight programs, Johnson, and not Marshall, should lead lander development.“We are deeply concerned that NASA is not only disregarding this history but that splitting up the work on the lander between two different geographic locations is an unnecessary and a counterproductive departure from the unquestionable success of the previous lunar lander program,” stated the letter, signed by Sens. Ted Cruz (R-Texas) and John Cornyn (R-Texas) and Rep. Brian Babin (R-Texas).The three members asked that NASA “hold off on any formal announcements until we receive a briefing on this matter that includes the timeline, projected cost, and rationale for this decision.” Babin, who was previously scheduled to be at the event, did not attend.
NASA did not changed by an inch since 1972. I felt I was reading a NASA history series document about the early Shuttle days, when JSC and Marshall fought bitterly over which would build what. Or 1984 with Freedom (disastrous) "work packages" worked out against any logic (except NASA centers logic !) that doomed the project for the next decade....
Out of curiosity how will this affect Mission Control? I’ve read that JSC will be keeping the crew cabin so I assume that Houston will still be the ones in contact with the crew, but/or will this be like the ISS Soyuz situation where during docking parts of it are (or maybe were, I’m not totally up to date in that regard) handed over to the Russian Mission Control in Korolyov?
Quote from: MaestroDavros on 08/19/2019 03:39 amOut of curiosity how will this affect Mission Control? I’ve read that JSC will be keeping the crew cabin so I assume that Houston will still be the ones in contact with the crew, but/or will this be like the ISS Soyuz situation where during docking parts of it are (or maybe were, I’m not totally up to date in that regard) handed over to the Russian Mission Control in Korolyov?Welcome to the forum!
One of the reasons why MSFC got the lander lead is because JSC is going to be busy handling ISS, Orion, Commercial Crew and the Gateway.
Quote from: GWH on 08/15/2019 05:01 pmLooks like things are proceeding swimmingly already: https://www.cruz.senate.gov/?p=press_release&id=4627This is Bridenstine's second run-in with Congress, the first being when he suggested flying EM-1 without SLS. At least the first battle was over something significant. I thought working with Congress was supposed to be Mr. B's forte.EDIT: Added link to GWH's post to provide context.
Looks like things are proceeding swimmingly already: https://www.cruz.senate.gov/?p=press_release&id=4627
Quote from: Proponent on 08/16/2019 02:17 amQuote from: GWH on 08/15/2019 05:01 pmLooks like things are proceeding swimmingly already: https://www.cruz.senate.gov/?p=press_release&id=4627This is Bridenstine's second run-in with Congress, the first being when he suggested flying EM-1 without SLS. At least the first battle was over something significant. I thought working with Congress was supposed to be Mr. B's forte.EDIT: Added link to GWH's post to provide context.This is working with congress. By giving the lander to Marshall, he has gained the support of Senator that decides whether or not funding for Artemis will even get voted on in the Senate. He may have annoyed the Texas delegation in the process, but it's probably just bark. There is a lot of Texas that isn't Houston, and most Texans care abut 300 new jobs not being created in Houston about as much as they would care about 300 new jobs not being created in Alabama. I suspect that at least the Senators from Texas will still vote pro-Artemis.... hopefully that wasn't too political. Apologies if it was.