Friday, August 21, 2020

Should NASA Send a SpaceX Dragon Capsule to the Moon?

That's not quite the title of a very worthwhile read from Ars Technica's Eric Berger this week.  His article is, “Could a Dragon spacecraft fly humans to the Moon? It’s complicated” and it's a long piece for Ars Technica but thoroughly worth the time to read.  

Think back three weeks to 8/2 as the Crew Dragon's Demo 2 mission is completing; this is where Berger begins.  

The landing came as NASA, at the direction of Vice President Mike Pence, is working urgently to return humans to the Moon by 2024. This is a herculean task for the agency’s administrator, Jim Bridenstine, who is balancing politics, funding, and technical hurdles to push NASA and its contractors forward.

Immediately after the splashdown and meeting the crew, Bridenstine plugged for the Artemis program, saying, “We have to make sure that another generation doesn’t miss this opportunity. Today was a great victory, but it was just a beginning. The Artemis Program is our sustainable return to the Moon.”  Bridenstine, under the direction of Vice President Pence, is driving toward a hard deadline of returning to the moon “to stay” by 2024 - or the end of the potential second Trump administration.  That's clearly part of the reasons for attacking this as a hard deadline; Moon or Bust.

The short answer to Eric Berger's question is that Crew Dragon could take a crew of three back to the moon with little modification, but it wasn't designed for that mission.  The emphasis appears to come from an op-ed published in the Washington Post on June 22nd, written by Robert Zubrin, founder of the Mars Society and president of Pioneer Astronautics, along with Homer Hickam, author of “Rocket Boys” (became the movie “October Sky,”) a retired NASA astronaut trainer, and spacecraft engineer.  Zubrin and Hickam argue essentially, why wait on the more expensive government vehicles when commercial solutions are already at hand?  They also come across as not being confident the Space Launch System and Orion capsule will be available in time for a 2024 mission.  I have to admit to leaning the same way. 

We recognize the hard work that NASA and its contractors have put forth on Orion/SLS, but they have simply been left behind by more nimble commercial companies. Dragon is not just cheaper than Orion; it is much better, because it is much lighter. The Dragon has a mass of 9.5 tons, compared to Orion’s 26.5 tons. Orion could have been designed lighter, but NASA has received so many conflicting directives from successive administrations — Orion was once required to fly to the asteroid belt! — it ended up with an elephant, not the racehorse it needed.

There are two big advantages to “running with what we got” - probably the biggest two advantages there can be:  money and time.  

The cost comparisons are extraordinary. According to an independent assessment by The Planetary Society, NASA has spent a total of $23.7 billion on development of the Orion spacecraft, which is designed to take up to four astronauts into deep space for 21 days. By comparison, through the Commercial Crew Program, NASA invested just $1.7 billion in Crew Dragon, which has now proven itself.

Then there are the launch vehicles. NASA is approaching a total investment of $20 billion in the Space Launch System rocket, which likely is still 18 months or longer from its first test flight. After this, the rocket is expected to cost at least $2 billion per launch. By contrast, SpaceX paid for the entirety of the Falcon Heavy’s development, and it would likely cost NASA between $150 and $200 million for lunar launch.

The Crew Dragon can carry four astronauts now - the next mission to the ISS will carry a crew of four.  The only issue is that the flight to the moon is longer than the uphill climb to the ISS - and it might be a bit crowded.  Additional storage space for consumables and other necessities (and probably some more elbowroom) are the changes that would have to be made for a version of the Dragon that could go to the moon.  According to an interview in the Ars article, SpaceX actually considered the design of alternate versions of the Dragon spacecraft: Gray Dragon and Red Dragon; both are named for the color of the world they would go to.  The plans might well exist now.

The Falcon Heavy might require tweaks to become man-rated as a booster, but NASA could workaround this by launching the Dragon on a Falcon 9, like they've just done and will do again soon, and rendezvous in space with a much heavier "other half" launched by the Falcon Heavy. 

Certainly, the politics of getting NASA to switch from the SLS/Orion to SpaceX/Dragon is a big deal, too.  Someone referred to the SLS as the Senate Launch System, in reference to Senator Richard Shelby (R) of Alabama and the Huntsville Space Center.  Senator Shelby has pretty much declared that humans must launch to the Moon inside the Orion spacecraft, on top of a Space Launch System rocket.  It's feasible that situations may overwhelm his control. 

Finally, there is the reality that the United States is borrowing heavily to dig itself out of the coronavirus crisis. At some point, belts will have to be tightened. If NASA could have a deep-space exploration program for $4 billion less a year by slashing Orion and the Space Launch System, some politicians may find that appealing.

 

I believe the vehicles they're comparing to here are the SLS Block 1B Crew and Block 2 Crew.

SpaceX does not have a lunar lander, at least not that I know of.  If they had one, they would have every part of a flight to land a couple of men on the moon Right Now.  I believe if they wanted to do it, they could land on the moon before 2024. 



11 comments:

  1. It occurs to me that SpaceX has a good deal of experience at landing rockets on solid surfaces.

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  2. Someone ought to ask Musk if they could land on the moon before 2024.

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  3. Well, by 2024 SpaceX may have a Starship moon rated.

    A dragon capsule could reach lunar orbit. The capsule is designed for long-duration flight. The service module can provide plenty of electricity. All you'd need is a modified Falcon 2nd stage, and some changes to the service module to provide additional life support and by the time they get all that done, well, Starship.


    Which is what the SpaceX website is saying:

    https://www.spacex.com/human-spaceflight/moon/index.html

    Though with the speed SpaceX does modifications, they could easily get Dragon to the moon.

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    1. Right. SpaceX has decided to put their metaphorical eggs in the basket of Starship as a replacement and upgrade to Falcon 9. Maybe that leaves the small sat launching business to Rocket Lab and one or two others; maybe Starship puts everything in orbit, as reusable as they expect it to be. At the rate they're going, they very well could meet that NASA contract to have a Starship to land on the moon.

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  4. How are the outputs of this particular form of man on the moon more valuable than the inputs? How does it make a profit? It doesn't, this is pork.

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  5. SpaceX has the capability. All they need is the green light to make it happen. My sense is that if you want to make it big and new, punch two or three robotic "base camp" missions to the Moon first with the sustainable part of the mission, followed by the people to set it up, or to do what they need to do with Moon Base 1 when they arrive six months later.

    I am not a proponent of a Mars mission at this point in our history because I think that the tech isn't there yet. (we could do it, but should we do it?) However, any Mars mission would require precision landing of the robotic missions necessary for a Mars base. This would be the way to demonstrate one more critical skill along that road.

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    1. I'm pretty much there with you. First off, it's a very dangerous mission and part (most?) of the danger comes from the travel times. A minimum of seven months in zero G can lead to lots of bone loss and even if they carry treadmills and exercise equipment, Gabby Giffords' husband had really tough physical ailments when he got back to Earth after a long stay on the ISS. They're assigned exercise time on the ISS, which clearly didn't prevent it.

      If they have to abandon Mars colony and wait in Mars orbit for the window for a return flight, that's enormously risky. I couldn't say if it's riskier waiting there or flying back with a year or more long flight. Probably about the same.

      What they need is nuclear engines on the ship going to and coming back from Mars. Accelerate half the trip, decelerate the other half. Both going to and coming home from Mars. It turns the trip into weeks instead of months. Living and working on Mars is going to be dangerous enough; let's not add the dangers of long periods in zero G.

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  6. What's needed for moving out is a working infrastructure in place before the people get there, and a durable supply line. We've been working with a Lewis & Clark model. What we need is Yellow Freight of The Skies. If you need a replacement pipe coupling, can you really print one? A good one? Grainger and McMaster will not deliver past low Earth orbit. This whole thing is a life support situation, all the time.

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    1. That appears to be in Musk's vision when he talks about a constant flow of Starships to Mars carrying cargo and back.

      It seems to me that a guy whose "other, other, other, business" is boring tunnels might export some of that to the moon or Mars to create underground habitat.

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    2. Probably all part of his Grand Plan, SiG!

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  7. I can't wait for the runaway debt and predictable hyperinflation of the dollar to sever the logistical tail of American governments at every level, and dismantle the NASA/Strategic Air Command's gun control of rockets.

    Then millions of nerds worldwide will build rockets, explore space, stay there a while, and accomplish actual exploration and colonization.

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