SpaceX Dragon XL

[JohnM]

snip

At the end of the surface mission, Lunar Starship returns to NRHO, and the crew can transfer return cargo into Cargo Starship, which then returns to Earth. Lunar Starship has much more upmass potential than NASA expected from HLS, and using Cargo Starship instead of Dragon XL would allow NASA to deliver all that fascinating lunar upmass to laboratories here on Earth.

snip

That's a great idea. I'd add that when you transfer the lunar cargo from LSS to Cargo Starship you could refuel LSS enough for it to land again on the moon in addition to resupplying consumables. That way you get a lunar base almost for free from your previously used LSS while getting tons of lunar material to study on Earth.

[Paul451]

The 100-day boiloff endurance is going to constrain the whole Artemis architecture, so there's very little value in having a logistics vehicle that can stick around longer. Lunar Starship will be limited to less than 100 days on the surface, and the initial design will be more limited than that. It may also require multiple refuelings to keep it alive between annual SLS/Orion missions.

The 100 day limit is just for the initial version which is only required to perform one landing (and return).

Just as reusability will only come from later contracts (NASA just wanted offerers to show that future "sustainability" was possible for each design,) presumably the loiter requirements will evolve based around developing mission goals and real experience. Longer duration might be preferred, or it might be rendered unnecessary by top-up fuelling from a cheap tanker sent from LEO every other month, or surface duration might become more important, or NASA might want an orbiting depot with a recondenser, or maybe polar ice is really common and accessible and ISRU LOx refuelling on the surface becomes quickly viable, or the whole thing might be cancelled or changed beyond recognition because of Congressional/Presidential changes.

[jarmumd]

So it seems NASA are not worried about the stress on the docking ports.  And of course, as an HLS lander, Starship needs to dock to Gateway anyway, and there has been no indication from NASA that that docking would be problematic.

I guess I'm just not sure NASA's really been looking at it much, beyond calling docking the black box in the powerpoint (the "then magic happens" box).

[sdsds]

It is a given in discussions these days that Starship can do any mission envisioned for any other spacecraft or launch system, and can do it better.

Still, it doesn't hurt for NASA to continue to fund missions flown by that old, obsolete Falcon Heavy. And if funding those launches, plus funding development of a bigger spacecraft than Dragon 2 makes NASA feel like they aren't putting all their eggs in the Starship basket — fine, let them.

At least, can we let that be the plan of record in this thread, until NASA says it isn't?

[docmordrid]

The 100-day boiloff endurance is going to constrain the whole Artemis architecture, so there's very little value in having a logistics vehicle that can stick around longer. Lunar Starship will be limited to less than 100 days on the surface, and the initial design will be more limited than that. It may also require multiple refuelings to keep it alive between annual SLS/Orion missions.

The 100 day limit is just for the initial version which is only required to perform one landing (and return).

Just as reusability will only come from later contracts (NASA just wanted offerers to show that future "sustainability" was possible for each design,) presumably the loiter requirements will evolve based around developing mission goals and real experience. Longer duration might be preferred,
>

In the Source Selection Statement Kathy Leuders made a big deal about NASA's loiter requirement only being 90 days and Starship HLS being capable of 100 days.

[Robotbeat]

Kathy Leuders is great.

[DreamyPickle]

The first crewed lander will be a Starship, this is guaranteed at this point. There's obviously no risk that Starship won't be available in time to support the gateway for a Starship landing on the Moon. Do we really care about support crew in lunar orbit without a mission?

Docking stresses and interfacing with Gateway is something that Starship will have to solve anyway. I don't know what this involved, can't they just overbuild the docking port on the starship to absorb any stress?

Only thrusters are required for undocking and eventual disposal and long-duration fuel storage is also something that SpaceX needs to solve anyway. The source-selection-statement mentioned 100 days loiter time which is already quite a lot and it's for liquid propellants. Storing propellants for thrusters over long durations should be easier, correct?

[klod]

As a reminder NASA hasn't selected yet 2nd provider for resupply mission. It could be NG or SNC. Then there should be also suppliers from ESA and JAXA. So when we are using Starship as lander we don't need Dragon XL. In other cases and I belive NASA, will push to get 2nd alternative lander,  they should have choice out of 3 regular ships.

[yg1968]

As a reminder NASA hasn't selected yet 2nd provider for resupply mission. It could be NG or SNC. Then there should be also suppliers from ESA and JAXA. So when we are using Starship as lander we don't need Dragon XL. In other cases and I belive NASA, will push to get 2nd alternative lander,  they should have choice out of 3 regular ships.

Fair point about JAXA's HTV-X but there is no plans for a second commercial Gateway logistics provider as of now. There is an on-ramp clause in the RFP but it hasn't been exercised as of now (it requires a new solicitation).

[yg1968]

This table from NASA's Management of the Gateway Program for Artemis Missions (IG-21-004) seems to show Dragon XL funding wouldn't ramp up until 2024.

If you look at Dragon XL's budget, it isn't that high, it's $264.6M through FY25, maybe NASA should keep Dragon XL given that it isn't that expensive.

[su27k]

It seems that NASA may realign Artemis-3 to happen along with unmanned Lunar Starship demo, and use Artemis-4 for manned landing. Assuming new Lunar Starship is used for both cases, then LSS can bring the supplies to Gateway instead of Dragon XL, this would obliviate the need for the first two Dragon XL missions and postpone Dragon XL to be later than 2025, by then it can be replaced by a version of Starship (Could still be LSS if they launch new one for each landing, or a crew version of Starship).

[yg1968]

It seems that NASA may realign Artemis-3 to happen along with unmanned Lunar Starship demo, and use Artemis-4 for manned landing. Assuming new Lunar Starship is used for both cases, then LSS can bring the supplies to Gateway instead of Dragon XL, this would obliviate the need for the first two Dragon XL missions and postpone Dragon XL to be later than 2025, by then it can be replaced by a version of Starship (Could still be LSS if they launch new one for each landing, or a crew version of Starship).

That first crewed Moon landing on Artemis IV rumor was prior to lunar Starship being awarded. I think that, as of now, Artemis III and crewed lunar Starship both align for the 2024 date. It's possible that either Orion/SLS or lunar Starship might slip from that date but it's not clear to me which one is more likely. Chances are that both will slip for roughly the same amount of time. At least, that's the impression that I get from reading the IG Report on the Artemis program.

[su27k]

New GLS contract modification on 4/1 for $121,814:

GATEWAY LOGISTICS SERVICES (GLS) SPACE EXPLORATION TECHNOLOGIES (SPACEX). THE PURPOSE OF THIS CONTRACT MODIFICATION IS TO ORDER SPECIAL TASK AND STUDY SX-307-21 PRIVATE CREW COMPARTMENT (PCC) AND WASTE MANAGEMENT SYSTEM (WMS) FEASIBILITY STUDY.

I wonder what is "Private Crew Compartment", is it something like the sleep station on ISS?

[cuddihy]

I would bet it's the reported crew quarters in the LSS mockup + a bathroom. Could be trialed first in a Dragon XL or in a starship performing a GLS service.

[gongora]

I would bet it's the reported crew quarters in the LSS mockup + a bathroom. Could be trialed first in a Dragon XL or in a starship performing a GLS service.

It's for Dragon XL specifically, for use when docked at Gateway.

[Robotbeat]

I would bet it's the reported crew quarters in the LSS mockup + a bathroom. Could be trialed first in a Dragon XL or in a starship performing a GLS service.

It's for Dragon XL specifically, for use when docked at Gateway.

Oh shoot, yeah, that’s gotta be what it’s for. I was thinking it had something to do with crewed Dragon on ISS. Dragon XL makes more sense.

[Tomness]

I would bet it's the reported crew quarters in the LSS mockup + a bathroom. Could be trialed first in a Dragon XL or in a starship performing a GLS service.

It's for Dragon XL specifically, for use when docked at Gateway.

Seems like a really good candidate for ISS before gateway

[Robotbeat]

I would bet it's the reported crew quarters in the LSS mockup + a bathroom. Could be trialed first in a Dragon XL or in a starship performing a GLS service.

It's for Dragon XL specifically, for use when docked at Gateway.

Seems like a really good candidate for ISS before gateway

Why would that be required?

[Tomness]

I would bet it's the reported crew quarters in the LSS mockup + a bathroom. Could be trialed first in a Dragon XL or in a starship performing a GLS service.

It's for Dragon XL specifically, for use when docked at Gateway.

Seems like a really good candidate for ISS before gateway

Why would that be required?

Be able to put up as much mass as ATV, station keeping, unpressurized cargo, sleep quaters & a bathroom. Good dry run before gateway. One off for ISS would be fine and Axiom can charter what ever they need for their station

[Norm38]

Seems like a really good candidate for ISS before gateway

Why would that be required?

Not required. But if commercial space is to accelerate, it’s a great idea. And get someone else to pay for it.
If they have that capability, use it. On ISS or another station.
Build more than one.