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Could a Dragon spacecraft fly humans to the Moon? Its complicated

Enlarge / Crew Dragon splashes down into the ocean on August 2.Bill Inglalls/NASA

On a recent Sunday afternoon, a black-and-white spacecraft raced through the atmosphere, ionizing molecules, and creating a plasma inferno. Amidst this fireball, two astronauts sheltered within the small haven of Dragonship Endeavour, as its carbon-based heat shield crisped and flaked away.

After a few torrid minutes, Endeavour shed most of its orbital velocity. Falling into the lower atmosphere, its parachutes deployed in a careful sequence, and the spacecraft floated down from blue skies into blue seas. Astronauts Doug Hurley and Bob Behnken were safe. They were home. For the first time in 4.5 decades, astronauts returned from space and splashed down into the ocean, like the Apollo-era heroes who walked across the Moon.

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 agencys administrator, Jim Bridenstine, who is balancing politics, funding, and technical hurdles to push NASA and its contractors forward.

Immediately after the landing, Bridenstine renewed his pitch for this Artemis Moon program during a splashdown news conference. Wearing a polo shirt emblazoned with the Artemis logo, he said, “We have to make sure that another generation doesnt miss this opportunity. Today was a great victory, but it was just a beginning. The Artemis Program is our sustainable return to the Moon.”

Then, Bridenstine added this comment: “If we do things right, we will get the strong bipartisan support that we need.” This was clearly a nod to funding needed to carry out Artemis. But what, exactly, does “do things right” mean, anyway? On the technical side, it means using space hardware that can get the job done. On the political side, it means making choices that satisfy those in Congress who pay the bills.

When it comes to spacecraft, rockets, and the Moon, these two things may not be the same.

This divide could not be more clear when Endeavour splashed down. The success of Crew Dragon, a relatively lightweight, modestly priced, and reusable spacecraft has led some aerospace engineers to suggest the space agency should scrap its plan to use larger, much more expensive vehicles—those championed by Congress for more than a decade—to perform the Moon landing.

  • Crew Dragon is brought on board the SpaceX recovery ship. NASA
  • Support teams arrive at the SpaceX Crew Dragon Endeavour spacecraft shortly after it landed. NASA
  • The spacecraft is hoisted onto the recovery ship. NASA
  • NASA astronauts Robert Behnken, left, and Douglas Hurley are seen inside the SpaceX Crew Dragon Endeavour spacecraft onboard the SpaceX GO Navigator recovery ship shortly after having landed. NASA
  • How was your ride home, Doug Hurley? NASA
  • Bob Behnken was in good spirits, too. NASA
  • NASA astronauts Douglas Hurley, left, and Robert Behnken prepare to depart their helicopter at Naval Air Station Pensacola after the duo landed in their SpaceX Crew Dragon Endeavour spacecraft. NASA
  • Crew Dragon nears splashdown in the Gulf of Mexico on Sunday. Bill Inglalls/NASA
  • An image of the parachutes falling into the water. NASA

After its successful landing in early August, Crew Dragon has proven itself, these advocates say. Its been to space and back with humans inside. With some modifications, it could be beefed up to support longer-duration missions to carry astronauts to lunar orbit and safely back to Earth. Why wait on the more expensive government vehicles when commercial solutions are already at hand?

“Do we really want to go to the Moon, or dont we?” asked Robert Zubrin, a US aerospace engineer who founded the Mars Society. “The question for Mike Pence is pretty simple: Do you really want to get to the Moon by 2024 or not? Because we have the tools to go.”

The current plan

Over the last 18 months, Bridenstine has crafted a plan that seeks to balance technical and political concerns in order to reach the Moon.

The administrator understands that commercial space, led by SpaceX, has stepped up and delivered for NASA. He has sought to include these new companies—which tend to work more quickly and for less guaranteed money than traditional aerospace firms such as Boeing—where possible in the Artemis Program. Theyve been allowed in the bidding for projects to build a lander to take humans from lunar orbit down to the Moons surface, as well as delivering cargo to the Moon.

Already, some in Congress have kvetched about this approach. Some House Democrats, including Kendra Horn of Oklahoma and Eddie Bernice Johnson of Texas, have argued that commercial companies should not be allowed to build the Human Landing System. Rather, they say, NASA should design, own, and operate the lander. So far, Bridenstine has been able to push back against this.

But there is a red line he dare not cross. In the Senate, the influential chairman of the Senate Appropriations Committee, Alabama Republican Richard Shelby, has said humans must launch to the Moon inside the Orion spacecraft, on top of a Space Launch System rocket. This may, generally, be considered the position of Congress. And if Bridenstine has any hope of winning Congressional funds for a lunar lander, he has to play by these rules.

Under the current plan, then, Bridenstine has shared contracts across a number of different contractors, both traditional and commercial space. “I think weve got a good balance,” he told Ars in an interview.

Politically, his strategy seems to be working, at least for the moment. While Artemis has not gotten all of the funding it needs, it is getting some. But what about technically? Is there any hope of making 2024?

A Gray Dragon alternative

More than a month before Endeavour returned to Earth, Zubrin and another rocket scientist, Homer Hickam, co-authored a provocative op-ed in The Washington Post titled “Send the SpaceX Dragon to the Moon.”

They cited several concerns about Orion, but the principal one is mass. At 26.5 tons, Orion and its Service Module are very heavy. Because of this girth, NASAs Space Launch System rocket cannot even get Orion all the way into low lunar orbit with enough maneuvering capability to get back to Earth.

“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,” Zubrin and Hickam wrote. “Dragon is not just cheaper than Orion; it is much better, because it is much lighter.”

Crew Dragon has a dry mass of less than 10 tons and 50 percent more internal space than the Apollo capsule that carried three astronauts to the Moon. SpaceXs Falcon Heavy rocket has the capacity to lift Crew Dragon and a “return stage” into lunar orbit. There, the vehicle would dock with a lunar lander that would carry the crew to the surface while the Crew Dragon capsule remains in low lunar orbit. After sciencing on the Moon, the astronauts would use the lander to return to the Crew Dragon, fire the return stage, and come home to Earth.

An interior shot of Crew Dragon during the Demo-2 mission.
An interior shot of Crew Dragon during the Demo-2 mission.SpaceX

It would be a tight fit for four people, traveling for three days to the Moon and three days back. But a “Gray” Dragon (like the color of the Moon) probably would be roomy enough.

When asked about the habitable volume inside Dragon, NASA astronaut Bob Behnken said, “Around the interior of the vehicle, there are some spaces folks can get out of their seats and kind of have their own small area to be in.” He added, “I wouldn't say its a phone booth, in terms of densely packed, but it definitely is cozy if you were to get up to four people.”

Advantages

The two primary advantages of this scenario are cost and, potentially, speed.

NASA now spends in excess of $3.5 billion a year on “development” costs for Orion and the Space Launch System, which are unlikely to fly crews into space before 2023. For this amount of money, NASA could procure several Crew Dragon spacecraft and Falcon Heavy rockets to launch them.

In their op-ed, Zubrin and Hickam make the argument that although NASA has taken commendable steps toward working with SpaceX and other more purely commercial space companies in spaceflight, they can and should go much further.

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 Heavys development, and it would likely cost NASA between $150 and $200 million for lunar launch.

Using SpaceXs capsule and rocket could also get NASA to the Moon by 2024, because they are now flight tested. There are no guarantees that Orion—a stripped-down version of which made a test flight in 2014—and the SLS rocket will pass their upcoming flight tests.

But, but, but

NASA Administrator Bridenstine was dismissive when asked about using Dragons instead of Orions for the Artemis Program. “I think its important to note that Crew Dragon was specifically designed for low Earth orbit and, in order to send it to the Moon, would require a ton of modifications,” he said. “Im not saying you couldnt modify it, but if you modified it, it would look a lot like Orion.”

To get a sense of how difficult it would be to modify Dragon for lunar operations, Ars spoke with Garrett Reismann, a former NASA astronaut who joined SpaceX in 2011 to direct crew operations. He left SpaceX about two years ago but remains a consultant. For this article, he made it clear he was not speaking on behalf of the company.

Although Crew Dragon was designed for low Earth orbit, the company did look beyond that, Reismann said. He cited the short-lived Red Dragon program, which at one time the company considered as a means of delivering cargo to Mars, before deciding to focus on Starship. Starship was deemed a better use of internal research and development funds than development of a Gray orRead More – Source

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