Home / Science / When NASA tries to land on the moon, it has many rockets to choose from

When NASA tries to land on the moon, it has many rockets to choose from



  If you want to buy a commercial SLS launch, you must also hire NASA's mobile starter.
Enlarge / If you want to buy a commercial SLS launch, you must also rent the mobile launch from NASA.

NASA

Last week, NASA held an "industry day" for companies hoping to win lunar land contracts from the government as part of its Artemis program. During the conference call, industry officials were able to ask questions about NASA's plans for how best to get astronauts from orbit around the moon, down to the surface and safely back.

After Vice President Mike Pence established the goal of landing people on the Moon in 2024, NASA officials have worked overtime for the past six months to put together mission plans and architectures to meet this deadline. The effort culminated with the release last week of a call asking the industry for the design of a human landing system.

There is much to digest in this document, which contains three dozen attachments and several changes. And industry officials must respond quickly with a deadline of November 1

to submit proposals. After reviewing the submissions, NASA will award two or more contracts that allow the companies to enter into the final design and development of Artemis Program lunar landers. The agency would like to have two different designs ahead of completion and believe that competition will result in faster, better hardware. But this may not be possible due to uncertain funding from Congress.

The Lander program asks much of the US aviation industry in terms of technology development and production in a short time. But one of the biggest and most immediate questions that every potential bidder will need to answer is launch. How will they get their lander hardware to the moon's orbit?

This is not an easy question to answer, as choosing a launch vehicle requires balancing political, technical and cost risks. There are also as many as five potential choices – Falcon Heavy, Vulcan-Centaur, New Glenn, Space Launch System (SLS) and Starship Super Heavy.

The task at the moment

Senate appropriation committee chairman, Alabama Republican Richard Shelby, has commissioned NASA to use the agency's SLS rocket to launch the Orion spacecraft crew to the lunar orbit. But for the lunar lander – parts that will be placed in the lunar orbit before the arrival of the crew – NASA has given contractors the flexibility to choose their own launch vehicle.

"We use a commercial design and development, end-to-end solution for this demonstration, and launch vehicles fall in line with that," Lisa Watson-Morgan said during the industry day meeting. She manages the Human Landing System program for NASA. "The commercial suppliers will procure a commercial launch vehicle," she added, noting that this vehicle and its costs would be part of each contractor's proposal to NASA.

  The three-stage moon landing has modules that can fit on commercial launch vehicles. "src =" https://cdn.arstechnica.net/wp-content/uploads/2019/10/HLS1.jpg "width =" 1277 "height =" 711

Three-step moonlander has modules that can fit on commercial launch vehicles .

NASA

Although it has acknowledged the openness of alternative designs for a lander, NASA is primarily looking at a three-stage lander that involves a "transfer vehicle" to take the lander from a high moon path to a lower and then a "provenance module" to bring the lander down to the surface. Along the way, the crew rides in a "ascent module", where they live below the lunar surface and where they launch from the lunar surface back to the waiting transfer vehicle.

NASA has estimated the mass values ​​for each of these land components, as shown in the image above. The total range of the modules is between 9 and 15 tonnes, although every contractor can obviously suggest vehicles of whatever mass they feel the job is done. The important thing to get out of this is that a heavy-lift rocket probably has to be able to throw 10 tonnes into the orbit. A payload capacity of 15 tonnes or more can accommodate most landing components.

Another important element of this is timing. During Industrial Day, Watson-Morgan said that NASA nominally goes for demonstrations of landing vehicles on the moon in August 2024. This means that they must be delivered to the moon's presence before then.

  The human landing system is increasing consideration. "Src =" https://cdn.arstechnica.net/wp-content/uploads/2019/10/HLS3.jpg "width =" 1348 "height =" 749

Human Considerations on the Landing System.

NASA

The rockets must either be certified by NASA's Launch Services program, have three successful launches in the same configuration, or be a commercial version of the SLS rocket. (We'll have more to say about a commercial version of SLS rockets later.) To be viable to launch landing elements, Watson-Morgan said, a proposed rocket must have met one of these criteria three months before "Flight Readiness Review "of a mission. Effectively, this means that a commercial rocket must have moved three missions before the spring of 2024.

With this basic understanding of technical requirements and timing requirements for a rocket to launch part of NASA's moon landing system to the moon, let's move on to the challengers .

Falcon Heavy

There is only one rocket today for NASA's lunar needs – SpaceX's Falcon Heavy booster. Not only is the rocket certified by NASA's Launch Services program, it has also moved three successful missions. Although it has not shown a mission to lunar orbit, the rocket has a capacity of at least 15 tons to lunar orbit per NASA's launch vehicle calculator.

Falcon Heavy also has other benefits. Unless it is flown in fully consumable mode – which it should be for a full 15 tonnes – its side-mounted boosters and possibly its center core can be reused. SpaceX also has the capacity to scale up production if more rockets are needed. And it will be difficult – if not impossible – for competitors to match Falcon Heavy prices starting at $ 90 million per launch.

For all this, however, it is not clear how many other entrepreneurs will use Falcon Heavy. Many of the expected bidders for lunar landers have their own rocket companies. For example, Lockheed Martin owns 50% of the United Launch Alliance and would therefore be unlikely to partner with SpaceX.

SpaceX has also built a successful model based on vertical integration. By not relying on traditional aerospace contractors, the company has been able to reduce costs and move quickly. At the same time, entrepreneurs who are invited to bid on parts of the lunar lander may be less willing to contract with SpaceX as a result.

What seems clear is that if the 2024 schedule remains crucial, the only safe rocket that will be ready to fly by the end of 2023 or early 2024 is Falcon Heavy.


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