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.