totm dec 2023 Artemis Discussion Thread

[Flavio hc16]

1 hour ago, darthgently said:

I could see having something habitable in lunar orbit to serve the same purpose as emergency cabins in the alps.  A small pressurized shelter with emergency consumables perhaps.  Maybe even a dedicated often manned research station just for supporting lunar research.  But the “gateway to mars” thing never rang right.

Gateway is useless even as a shelter, for 2 reason:

1) it gets to randevouz with the lunar polar orbit once every 2 weeks, so there is a high chance that if something happens, Earth might be closer (3 days) than gateway.

2) you are in an orbit that isn't shield half of the time by the moon so you only take half the radiation from the Sun in case of solar flare/storm.

[darthgently]

43 minutes ago, Flavio hc16 said:

Gateway is useless even as a shelter, for 2 reason:

1) it gets to randevouz with the lunar polar orbit once every 2 weeks, so there is a high chance that if something happens, Earth might be closer (3 days) than gateway.

2) you are in an orbit that isn't shield half of the time by the moon so you only take half the radiation from the Sun in case of solar flare/storm.

Yes, definitely not NRHO. We need repeater sats for continuous comms, not NRHO

Edited December 24, 2024 by darthgently

[Exoscientist]

On 12/14/2024 at 10:22 PM, Ultimate Steve said:

Given that the future of SLS's involvement in the Artemis program is up in shambles, I'm gonna muse over some various options for what could be done to replace it. From what I've thought of there's three main families of options.

 

Family 1: Distributed Lift.

This usually comes in the form of Orion getting launched on one rocket and a rocket stage getting launched on another rocket. Orion was at least at some point designed to take the force of engines firing through the docking port as it would have been required to back in the Constellation days. I'm unsure if this capability has been retained. Orion masses around 27 tons on its own, 34 tons with the launch escape system. This is beyond the capacity of Vulcan Centaur, but can fit on New Glenn and Falcon Heavy. Both would require a new adapter but it would likely be easier on New Glenn as it is wider, and you could taper down to Orion's diameter rather than having to taper up or do a Starliner style overhang - though Orion's diameter is smaller than the Falcon Fairing diameter so it shouldn't be too wide). Using Falcon Heavy gives you the advantages of flight heritage and having a crew access arm already at the launch pad (though it will likely need modifications to sit at the right height and have an appropriate interface).

A challenge with this approach is that Orion is designed to be vertically integrated. Both Falcon Heavy and New Glenn are horizontally integrated rockets. Orion can be transported horizontally without propellant and without the LAS attached, but sticking it on a Falcon style transporter erector fully fueled and with abort tower is going to take some effort. I'm not sure how much effort, but not zero effort.

The LEO launcher could also be a custom expendable variant of Starship - Starship of course has the performance to lift Orion's mass in reusable mode but it needs to be mounted on top for the LAS to work and Starship can't re-enter without its top. Starship is vertically integrated so it has that going for it, and it has more flight heritage than New Glenn, but SpaceX likely wouldn't want to make a custom expendable variant and changes to their launch towers especially with how much they are iterating right now. There's no clear winner for the launch vehicle IMO.

Then the question is, which launcher launches the space tug?

Vulcan Centaur can't, even if the structure was massless, 27 tons (VC's max payload) of propellant at an RL-10's isp can only just barely push Orion's mass to TLI. Real rockets aren't massless, real rockets have boiloff, and NASA doesn't like pushing rockets to their maximum (NASA's rocket performance calculator lists a maximum payload for reusable Falcon 9 that is below what they regularly do for Starlink, and Vulcan's numbers are lower on NASA's calculator than ULA's website).

Falcon Heavy fully expendable can do it with at least ten tons of margin. However, the timing would be tight without modifying it for long durations. Currently it can only do a few hours. Once you launch you have to commit fully to the other launch at the next launch window (unless you arrange the orbits at just the right way so you get two valid windows in rapid succession, but the odds that it lines up with the orbit you need to get to the moon are rather low). If you launch Falcon Heavy first and there's a problem with Orion, Falcon dies in orbit and the launch campaign is over. If Orion launches first, well, actually that could work. The crew may have to spend a few days hanging out in LEO, and risk having to come home if a showstopper issue delays Falcon more than a week or two. An amusing solution to this is to perform both launches timed simultaneously and with their launch commit criteria wired up to each other.

Falcon Upper Stage's acceleration at burnout would be very high compared to say, Centaur, but if Orion can still handle the forces it was expected to for Constellation, it can probably handle Falcon. If not, big problem, as at a minimum, peak force would be above 1 G.

New Glenn, I'm much less well versed on. BE3U has an isp of 445s, and at New Glenn's maximum payload (reused even) it should be able to do the job (though early versions of New Glenn are reportedly severely missing payload targets), though boiloff is as always a problem. They do want to create a variant of GS2 for refueling Cislunar Transporter so it may end up being a fairly straightforward modification.

Centaur V would be a really good option here as they really want to do zero boil off long duration, and it has a very low thrust, but unless they stick it on a New Glenn, it is not going to happen.

Starship is an option but largely redundant, same talking points as for Orion.

There's also the consideration that you would want to have this happening on two separate vehicles or deal with turning around your launch pad really quickly for 2 launches with the same vehicle (or building 2 launch pads, or doing zero boiloff forever duration upper stage).

 

Family 2: Single Launch Orion

This is a family inhabited solely by expendable Starship and even then only maybe. It is highly dependent on what the dry mass and payload of an expendable Starship would end up being. At one extreme you have a 120 ton vehicle with 100 tons of payload+prop that won't even get to 1500m/s of Delta-V, and at the other extreme you have a 40 ton vehicle with 200 tons of payload+prop which has 4.5km/s (waaaayyyyy more than needed). If you expend Super Heavy I can almost guarantee that the numbers close but SpaceX won't want to do that. Assuming that it does have the required performance it is an attractive option for its simplicity. Vertical integration, no rendezvous, no force through the docking port, and more flight heritage than any other option on the table besides Falcon Heavy. The catches are that for a reasonable timeframe you have to move Orion integration to Texas, you have to create a custom Starship variant, you have to crew rate Starship (and possibly commit to a design freeze) far ahead of schedule, with SpaceX really doesn't want to do, and you have to make modifications to Starship's launch tower.

 

Family 3: No Orion

There are 3 options in this family that immediately come to my mind as credible.

Option 1: Whatever Blue Origin is cooking up with Cislunar Transporter and their crew vehicle. Can't say much about that as it is still very much a mystery.

Option 2: Lunar Dragon. I don't think this is going to pan out as SpaceX doesn't want to invest in a system they hope to make obsolete in the same timeframe. New service module for Dragon, somehow maintaining abort capability, upgrading the heat shield. Dragon is ~12 tons, it needs ~8 tons of propellant to have as much Delta-V as Orion (though that may be a bit high as that doesn't take into account the propellant Dragon already carries), misc upgrades and service module mass, let's say it comes out to 1 more ton. The stack is 21 tons, and Falcon Heavy Expendable's TLI capacity is, well, unknown. Most estimates place it somewhere in the 21-23 ton range. On paper it fits, and SpaceX may do something funky with propellant utilization and a draco nozzle extension to reduce Lunar Dragon's mass, or not take as much Delta-V as Orion, so it wouldn't surprise me if it could work. But again, NASA does not like pushing its launch vehicles to their limits, so I have a hard time seeing this being selected.

Option 3: Lunar Starship, but not in the way you think

Depending on your chosen performance characteristics, Starship is maybe capable of going from LEO to the Lunar surface and back. Probably not. This requires a lot of optimism and no payload. However, I recently saw another option making its rounds online. The idea of using two Starships. HLS Starship is expended as normal. A crew Starship is refueled in LEO and goes to the Moon, transfers its crew to HLS, HLS lands and ascends, and crew Starship takes them back, and - crucially - propulsively brakes into LEO. It has the performance to do this, this saves the necessity to develop a Lunar rated heat shield if that becomes a significant barrier. Of course then you have to commit to putting crew on Starship through ascent and landing sooner than you otherwise would have, which is probably not the best idea.

Expanding upon this idea, depending on the masses involved, you might also be able to use crew ship to refuel HLS ship and reuse HLS ship, though it would probably require a Lunar rated heat shield if the refilling was to be done all at once, and delivery of heavy cargo to the Lunar surface would require some way to transfer that cargo from crew ship to HLS ship.

 

And then there's doubtless more options of various practicality that I haven't listed here or haven't thought of. The next few years will certainly be interesting. We may see a request for proposals for commercial Lunar crew transportation within the next few months. Reading the source selection statement for that is going to be interesting.

 

 

 Thanks for that discussion but a key option was missed: using a 3rd stage/lander. Robert Zubrin has made this argument numerous times that addition of a 3rd stage results in a more efficient architecture for the Moon or Mars.

 In fact it would result in single launch missions for both the Moon and Mars, no orbital refueling flights required at all. The expendable Starship at 250-ton capability and the reusable Starship V3 at 200-ton capacity have about twice the capacity of the Saturn V so would have about twice the capacity for single flight, round-trip missions to the Moon when using additional stage(s).

 And Zubrin’s Mars Direct approach could do Mars missions using two Saturn V class launches. So expendable Starship or Starship V3 could also do that in single launch format when using additional stage(s)

  Bob Clark

[darthgently]

1 hour ago, Exoscientist said:

 

 

 Thanks for that discussion but a key option was missed: using a 3rd stage/lander. Robert Zubrin has made this argument numerous times that addition of a 3rd stage results in a more efficient architecture for the Moon or Mars.

 In fact it would result in single launch missions for both the Moon and Mars, no orbital refueling flights required at all. The expendable Starship at 250-ton capability and the reusable Starship V3 at 200-ton capacity have about twice the capacity of the Saturn V so would have about twice the capacity for single flight, round-trip missions to the Moon when using additional stage(s).

 And Zubrin’s Mars Direct approach could do Mars missions using two Saturn V class launches. So expendable Starship or Starship V3 could also do that in single launch format when using additional stage(s)

  Bob Clark

Permanent Presence, not merely Boots on the Ground.  It Matters

[tater]

No one is stopping Zubrin from making a mini starship.

[Exoscientist]

14 hours ago, darthgently said:

Permanent Presence, not merely Boots on the Ground.  It Matters

Actually, at least for the reusable Starship V3, using the small 3rd stage/lander is cheaper on that measure as well. The current Artemis plan would make the Starship HLS expendable. But instead with a 3rd stage/lander only the cheaper, smaller lander would be expendable. It might be even the lander can be reusable as well.

Zubrin has made this point in regard to Mars missions as well. By sending the entire Starship to Mars it is out of use for two years. While using the smaller lander as the stage that goes to Mars, Starship can be returned to Earth for its many reuses after launch, and only the smaller lander is out of use for two years.

 There really is no logical reason to do multiple refueling, multiple launches for a single Moon or Mars mission when it can be done in a single launch format.

  Bob Clark

[farmerben]

Staging makes a lot of sense to me.  Reentry on Earth's atmosphere is a difficult and mass intensive.  No need to carry the same mass to the Moon and Mars only to bring it home again.

[darthgently]

I could see leaving a normal SS on the moon as a base with a very mini SS as a lunar ascent vehicle or something

[tater]

3 hours ago, farmerben said:

Staging makes a lot of sense to me.  Reentry on Earth's atmosphere is a difficult and mass intensive.  No need to carry the same mass to the Moon and Mars only to bring it home again.

I think there are loads of possible options for 9m dia bespoke spacecraft based on SS. I'm sure for the right price, SpaceX might entertain building them.

[magnemoe]

On 12/27/2024 at 4:54 PM, Exoscientist said:

 

 

 Thanks for that discussion but a key option was missed: using a 3rd stage/lander. Robert Zubrin has made this argument numerous times that addition of a 3rd stage results in a more efficient architecture for the Moon or Mars.

 In fact it would result in single launch missions for both the Moon and Mars, no orbital refueling flights required at all. The expendable Starship at 250-ton capability and the reusable Starship V3 at 200-ton capacity have about twice the capacity of the Saturn V so would have about twice the capacity for single flight, round-trip missions to the Moon when using additional stage(s).

 And Zubrin’s Mars Direct approach could do Mars missions using two Saturn V class launches. So expendable Starship or Starship V3 could also do that in single launch format when using additional stage(s)

  Bob Clark

Starship main issue is that its heavy, 150 ton dry mass I think, its two space shuttles. Now the cargo capacity is up to 10x heavier than the shuttle. 
I say for higher orbits like GEO having an reusable tug inside SS getting an satellite into GEO and then back to LEO and dock with an second SS makes sense.  
Disposable for cargo missions to moon and mars there the ship is raw materials or makeshift modules for storage or farming. 
For stuff like Europa sample return or Pluto orbiter / lander, 3rd stage with balloon tanks and an single raptor 3rd stage. Put SS in LEO, refuel it and 3rd stage. SS burn to raise Ap, note that 3rd stage is 500 ton now. Release and return SS to base. 3rd stage extend solar sail and wait until capture burn. 

[SunlitZelkova]

Apollo had Jerome Wiesner vs James Webb on whether to do direct ascent or lunar orbit rendezvous, Artemis has Bob vs basically everyone in this part of the forum on whether to do single launch or distributed launch w/ in-orbit refueling.

Never change, KSP forum. 

Edited December 29, 2024 by SunlitZelkova

[darthgently]

2 hours ago, SunlitZelkova said:

Apollo had Jerome Wiesner vs James Webb on whether to do direct ascent or lunar orbit rendezvous, Artemis has Bob vs basically everyone in this part of the forum on whether to do single launch or distributed launch w/ in-orbit refueling.

Never change, KSP forum. 

It depends on the mission.  I could see a direct with a 3rd stage with some comm sats for the moon or to sprinkle some robotic landers at various candidate sites for bases but see no reason to not send the next crewed mission to the moon with a full size lab and hab HLS base that would remain on site.  Just need an ascent vehicle to get back to LKO, which could be a crew rotation craft with fresh crew arriving later.  So HLS base craft interspersed with smaller crew rotation craft?  The HLS craft could be fairly custom depending on goal but the first at any site would be a hab and lab. 

[Ultimate Steve]

There may come a time when Starship is considered small. So maybe in some way the landings will be done with Mini Starship.

[Ultimate Steve]

I had a thought today, inspired by the "Elbonian Military" challenge going around the weaponry side of YouTube. The premise of that challenge is that you have been appointed the defense minister of Elbonia, and your task is to procure (insert some subset of military hardware, be it fighter jets or firearms, etc). However you're actually a spy for an enemy nation, and your goal is to procure the worst possible hardware while making it look to be, on paper, passable.

Since there's been so much discussion about which Lunar architecture is the best one, especially as there is a possibility that we might see an architecture change in the coming year or thereabouts, I thought it would be a fun thought experiment to try to come up with the worst possible Artemis architecture that is still within the realm of possibility (using existing or proposed hardware, or something that is reasonable to make).

You're all welcome to chime in with your own proposals!

 

Here's my attempt at a cursed alternate history Artemis program. I'll put it in a spoiler as it is quite long and it is not directly Artemis related so I'll minimize clutter:

Spoiler

Russia tried to keep Energia alive after the fall of the Soviet Union but it ultimately doesn't accomplish much and gets strung along much like how Angara is strung along today. Very slowly making very little progress but still alive and worked towards.

After Constellation is cancelled, Orion is cancelled with it.

A sole source award is given to Lockheed Martin for a new smaller crew capsule for LEO use only, reusing as much work from Orion as possible, but small enough to fit on existing EELVs. Thus, commercial crew never happens.

Work on the largest possible fundable rocket, a smaller version of SLS, is begun, but not very seriously as there are minimal missions that could use it.

In mid-2011, during a local maximum in US-Russia relations, the Artemis program is born, focused on returning to Cislunar space, fostering international cooperation, and spreading out the financial burden of such a large system to as many partners as possible. The success of using high performing and cost effective engines from Energia on Atlas V is still fresh in everyone's memory, so the new rocket, the LSL (Large Space Launcher) utilizes a shuttle derived core stage with Russian RD-0120 engines instead of RS-25s, as they are much cheaper, and the Energia cores they are supposed to launch are mostly sitting around waiting for other aspects of the program to catch up (In this timeline the engine program is just about the only well run part of Energia). It would also be sacrilege to expend reusable engines!

Boeing would build the core stage. The second stage is a Centaur III.

The rocket is much too small to need shuttle boosters, much to the sadness of the shuttle contractors, and thus, to foster international collaboration, the SRBs from the Ariane 5 are chosen instead. Arianespace would take this opportunity to attempt SRB reuse similar to that of the shuttle.

But what of the capsule, given that Orion died with Constellation last year? The Orel, of course! Or something that more closely resembles the CSTS than modern Orel. At the time, it was a little more highly regarded and in this alternate universe, Russia has a little more credibility as it was still technically the only nation operating (to some extent of the word) a SHLV. This capsule, a Russian-European collaboration, would be capable of entering Low Lunar Orbit.

The LSL would be capable of roughly 18ish tons to TLI.

The destination would initially be an amalgamation of various Lunar station proposals of the time, the modules of which would all be launched on Energia or the LSL. The details of this station are not important. To make room for this, the ISS will be shut down fairly early compared to our timeline, and there is less investment into commercial cargo.

No lander just yet.

Fast forward to 2014. Current geopolitical events (tm) kill any last scraps of Energia as the Zenit boosters are now impossible to procure. Somehow the LSL survives, though relations are very obviously strained.

Fast forward to 2017, and the new administration wants a Moon lander. In this timeline, the SpaceX proposal is not taken seriously (much like how the Boeing one was in our timeline). The chosen proposal is instead:

This thing! Clustering together off the shelf solid rocket motors for Lunar surface access! The ATK LSAM! One of the Lunar landers of all time!

SRB shuttle contractors are back and they are back with a vengeance!

However as you may have noticed, this 27 ton vehicle (or maybe that is just the descent stage?) is wholly incapable of reaching the Moon on existing rockets. Falcon Heavy may one day come about but no shot it fits in the fairing. But its key advantage is that the main propulsion systems already exist and theoretically it can be built quickly.

Another advantage is that due to its solid propellant, it can loiter for many months (possibly a year or two, presumably it would have solar panels in this timeline), which is critically important as it could only launch to LEO (more likely elliptical orbit) on an LSL, which will not have a high flight rate at all, so it will be months at best between the lander launch and the crew launch. It would launch with yet another SRB for Lunar orbit insertion.

It will reach the Moon via several launches of OmegA. Remember OmegA? Giant pile of SRBs with a Centaur on top? All of those shuttle SRB contractors had to do something in this timeline! OmegA (typing that stylization hurts my soul) would launch a Centaur with a docking port and mission extension package to elliptical orbit. The ATK LSAM would (quickly) rendezvous with it before the propellant boiled off, and the Centaur would fire to raise its orbit. This would repeat until the LSAM encountered the Moon and captured into elliptical orbit with its insertion motor.

But the station is in Low Lunar orbit!

A little earlier, asteroid redirect mission was cancelled, and the ion powered space tug for that would be repurposed as a Lunar space tug, which would rendezvous with the ATK LSAM, dock with it, and bring it down to the LLO station, as the LSAM wouldn't have the Delta-V (or precise liquid propellant systems) to enter LLO on its own. Kind of like the Deep Space Transport from our timeline.

Development proceeds.

2021 happens, incoming administration does not change much but looks for ways to kickstart a Mars program with existing technologies.

Fast forward to 2022, and the long awaited and long delayed first flight of the LSL occurs! Despite the delays, it is a glorious success. It delivers a mostly boilerplate Orel capsule on a Lunar flyby, and the European Service module performs beautifully. The Ariane 5 SRBs (which by now actually have been reused on Ariane 5 due to the funding and it turned out to be just as cost effective as you'd expect, as in, not) were successfully recovered.

Shortly later, geopolitics happens. Orel will no longer fly on LSL. Several flights worth of RD-0120s were shipped over (again, one of the few parts that actually worked well in this timeline) so LSL is not in particular danger. Falcon 9 still pops off in this timeline (though a bit slower) so Ariane 5 is still being retired, and ArianeSpace, fed up with the delays, commits to only as many more flights as there are RD-0120s for. LSL now has an expiration date.

Russia intends to pursue the Moon program on their own using (checks notes) A resurrected Energia using... Soyuzes... as boosters? And they're going to replace the European service module with something derived from Briz-M?

This, of course, puts the whole Artemis program in jeopardy as now you suddenly have no capsule.

What options do we have? There's the SpaceX Dragon 1. Remember they never made Dragon 2 in this timeline. But that will not work no matter how confident SpaceX is in their ability to make a crew rated capsule, as Dragon and Falcon Heavy simply cannot make it to Low Lunar Orbit and back even with all of the service module upgrades you can imagine. It wouldn't be reasonable in our timeline let alone this one.

Then there's the miniaturized Orion descendent, which has actually been popping off quite nicely and does need something to do as the ISS was supposed to be retired soon. Unfortunately it is utterly incapable of reaching the Moon without significant modifications.

Falcon Heavy has finally come around, and due to LSL's delays, some Lunar station modules are now launching on it. One of them, due to an administration's preference for Mars, was designed as a prototype long term Mars habitation module and is fairly chunky and designed for surviving in a large variety of orbits. Or at least can be modified to do so.

The advanced Habitation module will launch instead into LEO, where it is docked with the international space station initially and eventually a successor station (though maybe the ISS keeps getting extended in this timeline too). Mini Orion launches the crew to this station, and it remains at this station as a lifeboat (or in a standalone situation it would land as it couldn't loiter that long).

The Deep Space Transport would have moved to this station, it would dock with the Advanced Habitation Module. The crew would transfer into this module, and then embark on a months long ion powered cruise to the Lunar Station. The return trip would be quite similar 

The long trips and radiation exposure would be sold as "getting experience for Mars" and stuff. But that one habitation module is not enough to sustain the crew, and there would need to be an initial kick to get through the Van Allen belts. Thus, another OmegA-Centaur would dock with the AHM + DST, and boost it to an elliptical orbit where it won't cross the radiation belts.

However, one module can't support a crew of four (likely just two in this timeline) for months and also supply the Lunar Station (or what is left of it). Thus, a Lunar rated Cygnus would be launched on a Falcon Heavy halfway through the mission. It lacks the Delta-V to get into LLO, so the DST would dock with it while carrying the AHM down. The cargo would be transferred from the Cygnus into the AHM, and then the Cygnus would crash into the Moon. Then when the AHM+DST finally reached the Lunar Station, the cargo would be transferred.

On the way back to LEO, yet another OmegA-Centaur would bring the AHM+DST back to LEO.

If the program somehow survived to the point where the limited RD-0120s were in danger of being lost, I'd imagine that the program would either cancel the LSL pivot to Mars (As dumb as it is, the AHM+DST being successfully used in such a risky long duration architecture does mean it can fairly be easily made into a Mars flyby or maybe even orbit vehicle), or retrofit RS-25s, and somehow create new boosters from the Ariane 6 or OmegA. SpaceX sticks with carbon fiber for Starship and Starship isn't really taken seriously as progress becomes very slow.

And that's it!

 

To recap, a typical Artemis mission would look like this:

1. The ion powered Deep Space Transport (DST) undocks from the Lunar Station and proceeds to an elliptical Lunar orbit
2. The Advanced Habitation Module (AHM) is resupplied and refurbished at the ISS or its successor
3. A Large Space Launcher (LSL) (American rocket with a limited stock of Russian engines and a limited stock of European boosters) launches the ATK Lunar Surface Access Module (LSAM) (a bunch of STAR SRBs vaguely in the shape of a moon lander) into Elliptical Earth orbit.
4. A series of OmegA-Centaurs modified for extended duration (maybe a small number of tens of hours?) are launched. The LSAM rapidly rendezvouses with each one hours after launched, and each Centaur progressively boosts the ATK LSAM into a more and more elliptical orbit.
5. The ATK LSAM inserts itself into an elliptical Lunar orbit with one solid rocket motor.
6. The DST picks up the LSAM and carries it down to the Lunar Station.
7. It is likely that due to the times involved, this architecture would involve two separate DSTs, but I would like to imagine that the DST then begins a long journey from the Lunar Station down to Low Earth Orbit, where it docks with the International Space Station or whatever its successor ends up being.
8. A logistics vehicle is launched to refuel and refurbish the DST with the help of the space station's crew
9. Crew are launched on board the mini-Orion to the space station where they then board the AHM. The mini-Orion is left at the LEO station to be used as a backup escape ship for the station crew.
10. An OmegA-Centaur is launched to boost the combination AHM-DST into an orbit that takes it up above the Van Allen belts. This would somehow require convincing NASA that not having a return capsule with the crew at all times is a good idea.
11. The AHM-DST makes a slow months long ion powered transfer to Elliptical Lunar Orbit.
12. A Falcon Heavy with a Cygnus is launched carrying additional supplies, and rendezvouses with the AHM-DST in Elliptical Lunar Orbit. The supplies are transferred, and trash is thrown away in the Cygnus, which is de-orbited into the Moon or disposed of in deep space.
13. A The AHM-DST slowly lowers itself into Low Lunar Orbit and docks with the Lunar Station.
14. The crew do a 1 week trip to the Lunar surface in the LSAM
15. Presumably the crew stay on the Lunar Station for some time as there's no point if they don't stay there for a while (perhaps there are multiple AHM-DSTs shuttling crew back and forth? Or perhaps Russia somehow manages to make Energia-Soyuz-Orel work without a European service module and visits the station from time to time?)
16. The AHM-DST departs with the crew on board and returns to an Elliptical Earth Orbit on another months long ion powered journey
17. Yet another OmegA-Centaur is launched to quickly bring the AHM-DST below the Van-Allen belts
18. The AHM-DST docks to the LEO space station
19. The crew returns to Earth on board a mini Orion (presumably the mini Orions are rotated in the same way the Soyuzes are so probably not the exact same mini Orion)

Let me know if you can come up with anything even more cursed than that!

Edit: Parts of this idea were contributed by haida, Stonesmile, and RyanRising on the RO Discord.

Edited December 30, 2024 by Ultimate Steve

[tater]

More cursed?

Use SLS and Orion, with a lander built by Boeing.

And some part built by Arianespace.

[darthgently]

31 minutes ago, Ultimate Steve said:

I had a thought today, inspired by the "Elbonian Military" challenge going around the weaponry side of YouTube. The premise of that challenge is that you have been appointed the defense minister of Elbonia, and your task is to procure (insert some subset of military hardware, be it fighter jets or firearms, etc). However you're actually a spy for an enemy nation, and your goal is to procure the worst possible hardware while making it look to be, on paper, passable.

Since there's been so much discussion about which Lunar architecture is the best one, especially as there is a possibility that we might see an architecture change in the coming year or thereabouts, I thought it would be a fun thought experiment to try to come up with the worst possible Artemis architecture that is still within the realm of possibility (using existing or proposed hardware, or something that is reasonable to make).

You're all welcome to chime in with your own proposals!

 

Here's my attempt at a cursed alternate history Artemis program. I'll put it in a spoiler as it is quite long and it is not directly Artemis related so I'll minimize clutter:

  Hide contents

Russia tried to keep Energia alive after the fall of the Soviet Union but it ultimately doesn't accomplish much and gets strung along much like how Angara is strung along today. Very slowly making very little progress but still alive and worked towards.

After Constellation is cancelled, Orion is cancelled with it.

A sole source award is given to Lockheed Martin for a new smaller crew capsule for LEO use only, reusing as much work from Orion as possible, but small enough to fit on existing EELVs. Thus, commercial crew never happens.

Work on the largest possible fundable rocket, a smaller version of SLS, is begun, but not very seriously as there are minimal missions that could use it.

In mid-2011, during a local maximum in US-Russia relations, the Artemis program is born, focused on returning to Cislunar space, fostering international cooperation, and spreading out the financial burden of such a large system to as many partners as possible. The success of using high performing and cost effective engines from Energia on Atlas V is still fresh in everyone's memory, so the new rocket, the LSL (Large Space Launcher) utilizes a shuttle derived core stage with Russian RD-0120 engines instead of RS-25s, as they are much cheaper, and the Energia cores they are supposed to launch are mostly sitting around waiting for other aspects of the program to catch up (In this timeline the engine program is just about the only well run part of Energia). It would also be sacrilege to expend reusable engines!

Boeing would build the core stage. The second stage is a Centaur III.

The rocket is much too small to need shuttle boosters, much to the sadness of the shuttle contractors, and thus, to foster international collaboration, the SRBs from the Ariane 5 are chosen instead. Arianespace would take this opportunity to attempt SRB reuse similar to that of the shuttle.

But what of the capsule, given that Orion died with Constellation last year? The Orel, of course! Or something that more closely resembles the CSTS than modern Orel. At the time, it was a little more highly regarded and in this alternate universe, Russia has a little more credibility as it was still technically the only nation operating (to some extent of the word) a SHLV. This capsule, a Russian-European collaboration, would be capable of entering Low Lunar Orbit.

The LSL would be capable of roughly 18ish tons to TLI.

The destination would initially be an amalgamation of various Lunar station proposals of the time, the modules of which would all be launched on Energia or the LSL. The details of this station are not important. To make room for this, the ISS will be shut down fairly early compared to our timeline, and there is less investment into commercial cargo.

No lander just yet.

Fast forward to 2014. Current geopolitical events (tm) kill any last scraps of Energia as the Zenit boosters are now impossible to procure. Somehow the LSL survives, though relations are very obviously strained.

Fast forward to 2017, and the new administration wants a Moon lander. In this timeline, the SpaceX proposal is not taken seriously (much like how the Boeing one was in our timeline). The chosen proposal is instead:

This thing! Clustering together off the shelf solid rocket motors for Lunar surface access! The ATK LSAM! One of the Lunar landers of all time!

SRB shuttle contractors are back and they are back with a vengeance!

However as you may have noticed, this 27 ton vehicle (or maybe that is just the descent stage?) is wholly incapable of reaching the Moon on existing rockets. Falcon Heavy may one day come about but no shot it fits in the fairing. But its key advantage is that the main propulsion systems already exist and theoretically it can be built quickly.

Another advantage is that due to its solid propellant, it can loiter for many months (possibly a year or two, presumably it would have solar panels in this timeline), which is critically important as it could only launch to LEO (more likely elliptical orbit) on an LSL, which will not have a high flight rate at all, so it will be months at best between the lander launch and the crew launch. It would launch with yet another SRB for Lunar orbit insertion.

It will reach the Moon via several launches of OmegA. Remember OmegA? Giant pile of SRBs with a Centaur on top? All of those shuttle SRB contractors had to do something in this timeline! OmegA (typing that stylization hurts my soul) would launch a Centaur with a docking port and mission extension package to elliptical orbit. The ATK LSAM would (quickly) rendezvous with it before the propellant boiled off, and the Centaur would fire to raise its orbit. This would repeat until the LSAM encountered the Moon and captured into elliptical orbit with its insertion motor.

But the station is in Low Lunar orbit!

A little earlier, asteroid redirect mission was cancelled, and the ion powered space tug for that would be repurposed as a Lunar space tug, which would rendezvous with the ATK LSAM, dock with it, and bring it down to the LLO station, as the LSAM wouldn't have the Delta-V (or precise liquid propellant systems) to enter LLO on its own. Kind of like the Deep Space Transport from our timeline.

Development proceeds.

2021 happens, incoming administration does not change much but looks for ways to kickstart a Mars program with existing technologies.

Fast forward to 2022, and the long awaited and long delayed first flight of the LSL occurs! Despite the delays, it is a glorious success. It delivers a mostly boilerplate Orel capsule on a Lunar flyby, and the European Service module performs beautifully. The Ariane 5 SRBs (which by now actually have been reused on Ariane 5 due to the funding and it turned out to be just as cost effective as you'd expect, as in, not) were successfully recovered.

Shortly later, geopolitics happens. Orel will no longer fly on LSL. Several flights worth of RD-0120s were shipped over (again, one of the few parts that actually worked well in this timeline) so LSL is not in particular danger. Falcon 9 still pops off in this timeline (though a bit slower) so Ariane 5 is still being retired, and ArianeSpace, fed up with the delays, commits to only as many more flights as there are RD-0120s for. LSL now has an expiration date.

Russia intends to pursue the Moon program on their own using (checks notes) A resurrected Energia using... Soyuzes... as boosters? And they're going to replace the European service module with something derived from Briz-M?

This, of course, puts the whole Artemis program in jeopardy as now you suddenly have no capsule.

What options do we have? There's the SpaceX Dragon 1. Remember they never made Dragon 2 in this timeline. But that will not work no matter how confident SpaceX is in their ability to make a crew rated capsule, as Dragon and Falcon Heavy simply cannot make it to Low Lunar Orbit and back even with all of the service module upgrades you can imagine. It wouldn't be reasonable in our timeline let alone this one.

Then there's the miniaturized Orion descendent, which has actually been popping off quite nicely and does need something to do as the ISS was supposed to be retired soon. Unfortunately it is utterly incapable of reaching the Moon without significant modifications.

Falcon Heavy has finally come around, and due to LSL's delays, some Lunar station modules are now launching on it. One of them, due to an administration's preference for Mars, was designed as a prototype long term Mars habitation module and is fairly chunky and designed for surviving in a large variety of orbits. Or at least can be modified to do so.

The advanced Habitation module will launch instead into LEO, where it is docked with the international space station initially and eventually a successor station (though maybe the ISS keeps getting extended in this timeline too). Mini Orion launches the crew to this station, and it remains at this station as a lifeboat (or in a standalone situation it would land as it couldn't loiter that long).

The Deep Space Transport would have moved to this station, it would dock with the Advanced Habitation Module. The crew would transfer into this module, and then embark on a months long ion powered cruise to the Lunar Station. The return trip would be quite similar 

The long trips and radiation exposure would be sold as "getting experience for Mars" and stuff. But that one habitation module is not enough to sustain the crew, and there would need to be an initial kick to get through the Van Allen belts. Thus, another OmegA-Centaur would dock with the AHM + DST, and boost it to an elliptical orbit where it won't cross the radiation belts.

However, one module can't support a crew of four (likely just two in this timeline) for months and also supply the Lunar Station (or what is left of it). Thus, a Lunar rated Cygnus would be launched on a Falcon Heavy halfway through the mission. It lacks the Delta-V to get into LLO, so the DST would dock with it while carrying the AHM down. The cargo would be transferred from the Cygnus into the AHM, and then the Cygnus would crash into the Moon. Then when the AHM+DST finally reached the Lunar Station, the cargo would be transferred.

On the way back to LEO, yet another OmegA-Centaur would bring the AHM+DST back to LEO.

If the program somehow survived to the point where the limited RD-0120s were in danger of being lost, I'd imagine that the program would either cancel the LSL pivot to Mars (As dumb as it is, the AHM+DST being successfully used in such a risky long duration architecture does mean it can fairly be easily made into a Mars flyby or maybe even orbit vehicle), or retrofit RS-25s, and somehow create new boosters from the Ariane 6 or OmegA. SpaceX sticks with carbon fiber for Starship and Starship isn't really taken seriously as progress becomes very slow.

And that's it!

 

To recap, a typical Artemis mission would look like this:

1. The ion powered Deep Space Transport (DST) undocks from the Lunar Station and proceeds to an elliptical Lunar orbit
2. The Advanced Habitation Module (AHM) is resupplied and refurbished at the ISS or its successor
3. A Large Space Launcher (LSL) (American rocket with a limited stock of Russian engines and a limited stock of European boosters) launches the ATK Lunar Surface Access Module (LSAM) (a bunch of STAR SRBs vaguely in the shape of a moon lander) into Elliptical Earth orbit.
4. A series of OmegA-Centaurs modified for extended duration (maybe a small number of tens of hours?) are launched. The LSAM rapidly rendezvouses with each one hours after launched, and each Centaur progressively boosts the ATK LSAM into a more and more elliptical orbit.
5. The ATK LSAM inserts itself into an elliptical Lunar orbit with one solid rocket motor.
6. The DST picks up the LSAM and carries it down to the Lunar Station.
7. It is likely that due to the times involved, this architecture would involve two separate DSTs, but I would like to imagine that the DST then begins a long journey from the Lunar Station down to Low Earth Orbit, where it docks with the International Space Station or whatever its successor ends up being.
8. A logistics vehicle is launched to refuel and refurbish the DST with the help of the space station's crew
9. Crew are launched on board the mini-Orion to the space station where they then board the AHM. The mini-Orion is left at the LEO station to be used as a backup escape ship for the station crew.
10. An OmegA-Centaur is launched to boost the combination AHM-DST into an orbit that takes it up above the Van Allen belts. This would somehow require convincing NASA that not having a return capsule with the crew at all times is a good idea.
11. The AHM-DST makes a slow months long ion powered transfer to Elliptical Lunar Orbit.
12. A Falcon Heavy with a Cygnus is launched carrying additional supplies, and rendezvouses with the AHM-DST in Elliptical Lunar Orbit. The supplies are transferred, and trash is thrown away in the Cygnus, which is de-orbited into the Moon or disposed of in deep space.
13. A The AHM-DST slowly lowers itself into Low Lunar Orbit and docks with the Lunar Station.
14. The crew do a 1 week trip to the Lunar surface in the LSAM
15. Presumably the crew stay on the Lunar Station for some time as there's no point if they don't stay there for a while (perhaps there are multiple AHM-DSTs shuttling crew back and forth? Or perhaps Russia somehow manages to make Energia-Soyuz-Orel work without a European service module and visits the station from time to time?)
16. The AHM-DST departs with the crew on board and returns to an Elliptical Earth Orbit on another months long ion powered journey
17. Yet another OmegA-Centaur is launched to quickly bring the AHM-DST below the Van-Allen belts
18. The AHM-DST docks to the LEO space station
19. The crew returns to Earth on board a mini Orion (presumably the mini Orions are rotated in the same way the Soyuzes are so probably not the exact same mini Orion)

Let me know if you can come up with anything even more cursed than that!

Edit: Parts of this idea were contributed by haida, Stonesmile, and RyanRising on the RO Discord.

 I don’t see the point of purposely imagining a more depressing space exploration future when the actual one is looking up.  It takes a lot to get a decent vision out there.  Why confound it?

[Ultimate Steve]

22 minutes ago, darthgently said:

I don’t see the point of purposely imagining a more depressing space exploration future when the actual one is looking up.  It takes a lot to get a decent vision out there.  Why confound it?

I thought it would be funny to think up the most absurd architecture possible with the available pieces. An exercise in absurdity and a look at some bullets we may have dodged. Obviously I'm not advocating for that architecture.

Edited December 30, 2024 by Ultimate Steve

[darthgently]

1 hour ago, Ultimate Steve said:

I thought it would be funny to think up the most absurd architecture possible with the available pieces. An exercise in absurdity and a look at some bullets we may have dodged. Obviously I'm not advocating for that architecture.

Idk, just seems more like something for the Lounge or a separate topic, not the official Artemis topic as it is requesting a lot of off topic input.  Am I crazy?

[Exoscientist]

On 12/28/2024 at 10:30 PM, SunlitZelkova said:

Apollo had Jerome Wiesner vs James Webb on whether to do direct ascent or lunar orbit rendezvous, Artemis has Bob vs basically everyone in this part of the forum on whether to do single launch or distributed launch w/ in-orbit refueling.

Never change, KSP forum. 

 

 Robert Zubrin has made this point numerous times:

 

https://x.com/robert_zubrin/status/1374861051490000896?s=61

https://x.com/robert_zubrin/status/1725747455247979000?s=61

https://x.com/robert_zubrin/status/1278300197664120833?s=61

https://x.com/robert_zubrin/status/1256718751619145728?s=61

https://x.com/robert_zubrin/status/1256574624202018819?s=61

https://x.com/robert_zubrin/status/1256571091100725249?s=61

https://x.com/robert_zubrin/status/1192796619894185987?s=61

https://x.com/robert_zubrin/status/1192785320011415552?s=61

https://x.com/robert_zubrin/status/1192444670191624192?s=61

https://x.com/robert_zubrin/status/1178265541342941184?s=61

https://x.com/robert_zubrin/status/1127195497964478464?s=61

https://x.com/robert_zubrin/status/1127283625366568961?s=61

 

 And finally:

  Bob Clark

 

 

[darthgently]

7 hours ago, Exoscientist said:

 

 Robert Zubrin has made this point numerous times:

 

https://x.com/robert_zubrin/status/1374861051490000896?s=61

https://x.com/robert_zubrin/status/1725747455247979000?s=61

https://x.com/robert_zubrin/status/1278300197664120833?s=61

https://x.com/robert_zubrin/status/1256718751619145728?s=61

https://x.com/robert_zubrin/status/1256574624202018819?s=61

https://x.com/robert_zubrin/status/1256571091100725249?s=61

https://x.com/robert_zubrin/status/1192796619894185987?s=61

https://x.com/robert_zubrin/status/1192785320011415552?s=61

https://x.com/robert_zubrin/status/1192444670191624192?s=61

https://x.com/robert_zubrin/status/1178265541342941184?s=61

https://x.com/robert_zubrin/status/1127195497964478464?s=61

https://x.com/robert_zubrin/status/1127283625366568961?s=61

 

 And finally:

  Bob Clark

 

 

Zubrin is, enthusiastic, and seems to downplay the value of pressurized volume permanently delivered to the surfaces of the Moon and Mars.  Merely getting that much scrap steel to these surfaces makes HLS worth it.  Where Zubrin’s ideas can contribute is an integrated smaller surface crew  changeover vehicle to ferry crew to and from the bases

[magnemoe]

1 hour ago, darthgently said:

Zubrin is, enthusiastic, and seems to downplay the value of pressurized volume permanently delivered to the surfaces of the Moon and Mars.  Merely getting that much scrap steel to these surfaces makes HLS worth it.  Where Zubrin’s ideas can contribute is an integrated smaller surface crew  changeover vehicle to ferry crew to and from the bases

For an base SS is very nice. As an lander for an 2-4 man landing its way overkill, don't agree with the aircraft carrier, its more like taking an big rig to buy groceries. 
Now this might make sense if you only have an big rig as its cheaper than an taxi, SpaceX is making an manned version anyway and paying for an version to land on the moon might be faster and cheaper than an dedicated lander even if cheaper to operate in the long run. 

[darthgently]

16 minutes ago, magnemoe said:

For an base SS is very nice. As an lander for an 2-4 man landing its way overkill, don't agree with the aircraft carrier, its more like taking an big rig to buy groceries. 
Now this might make sense if you only have an big rig as its cheaper than an taxi, SpaceX is making an manned version anyway and paying for an version to land on the moon might be faster and cheaper than an dedicated lander even if cheaper to operate in the long run. 

Off the cuff, I’m thinking HLS doesn’t need header tanks.  This frees up the nose section for variations of a detachable “3rd stage”.  

1) Lunar lander/ascent to/from LLO (fairing covered during launch)

2) Earth return capsule

3) MAV on Mars?

The idea being that once a Starship lands on the Moon or Mars, the default is it stays as valuable pressurized space, or refined near-raw materials at worst. Would be nice to get the engines back from the Moon to Earth for reuse somehow also if feasible

 

Edited 58 minutes ago by darthgently