As NASA tries to land on the Moon, it has plenty of rockets to choose from

[Karlston]

As NASA tries to land on the Moon, it has plenty of rockets to choose from

One of them is even something the agency is calling a "commercial" SLS.

Enlarge / If you want to buy a commercial SLS launch, you also need to rent the mobile launcher from NASA.

NASA

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

 

After Vice President Mike Pence established the goal of landing humans on the Moon by 2024, NASA officials have been working overtime throughout the last six months to put together mission plans and architectures to meet this deadline. The effort culminated in the release last week of a solicitation that asks industry for designs of a human landing system.

 

There is a lot to digest in this document, which contains three-dozen attachments and several amendments. And industry officials must respond quickly, with a Nov. 1 deadline to return proposals. After reviewing the submissions, NASA will award two or more contracts that will allow firms to move into the final design and development of Artemis Program lunar landers. The agency would like to have two different designs move forward toward completion, believing that competition will result in faster, better hardware. But this may not be possible due to uncertain funding from Congress.

 

The lander program asks a lot of the US aerospace industry in terms of technology development and production in a short period of time. Yet one of the biggest and most immediate questions each potential bidder will have to answer involves launch. How will they get their lander hardware to lunar orbit?

 

This is not an easy question to answer, because the choice of 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 hand

The chairman of the Senate Appropriations Committee, Alabama Republican Richard Shelby, has mandated that NASA use the agency's SLS rocket to launch the crewed Orion spacecraft to lunar orbit. But for the lunar lander—elements of which will be pre-positioned in lunar orbit prior to the crew's arrival—NASA has given contractors the flexibility to choose their own launch vehicle.

 

"We are employing a commercial design and development, end-to-end solution for this demonstration, and launch vehicles fall in line with that," said Lisa Watson-Morgan during the industry day meeting. She is managing the Human Landing System program for NASA. "The commercial providers shall 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 lunar lander has modules that could fit on commercial launch vehicles.

NASA

Although it has professed an openness to 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 lunar orbit to a lower one and then a "descent module" to carry the lander down to the surface. Along the way, the crew rides in an "ascent module," where they live during the lunar surface stay and in which they launch from the Moon's surface back to the waiting transfer vehicle.

 

NASA has estimated the mass values for each of these lander components, as shown in the image above. The overall range of the modules is between 9 and 15 metric tons, although obviously each contractor may propose vehicles of whatever mass they feel gets the job done. The important thing to glean from this is that, at a minimum, a heavy-lift rocket probably needs to be able to throw 10 tons into lunar orbit. A payload capacity of 15 tons or more could accommodate most lander components.

 

Another key element of this is timing. During industry day, Watson-Morgan said NASA is nominally moving toward demonstrations of lunar landing vehicles in the August 2024 time frame. This means they would have to be delivered to the vicinity of the Moon before then.

Human Landing System booster considerations.

NASA

 

The rockets themselves 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 the SLS rocket later.) To be viable for launching lander elements, Watson-Morgan said, a proposed rocket must have met one of these criteria three months before the "Flight Readiness Review" of a mission. Effectively, this means a commercial rocket must have flown three missions before the spring of 2024 at the very latest.

 

With this basic understanding of technical and timing requirements for a rocket to launch part of NASA's lunar lander system to the Moon, let's move on to the contenders.

Falcon Heavy

There is just one rocket available 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 flown three successful missions. Although it has not demonstrated a mission to lunar orbit, the rocket has a capacity of at least 15 tons to lunar orbit, per NASA's launch vehicle calculator.

 

The Falcon Heavy has other advantages as well. Unless it is flown in fully expendable mode—which it would need to be for a full 15 tons—its side-mounted boosters and potentially its center core could 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 pricing that begins at $90 million per launch.

 

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

 

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SpaceX has also built a successful model based on vertical integration. By not relying on traditional aerospace contractors, the company has been able to slash costs as well as move quickly. At the same time, contractors involved in bidding for elements of the lunar lander may be less willing to contract with SpaceX as a result.

 

What does seem clear is that if the 2024 schedule remains paramount, then the only sure-thing rocket that will be ready to fly by late 2023 or early 2024 is the Falcon Heavy.

Vulcan-Centaur

It's a good bet that the Vulcan-Centaur rocket built by United Launch Alliance (ULA) will play a role in the lunar program. This rocket remains on track to make a debut in 2021, according to the company, and if co-owners Lockheed and Boeing win contracts for pieces of the lunar lander, they probably will have the Vulcan as their booster of choice.

 

In a configuration with six side-mounted boosters, and a Centaur upper stage with two engines instead of one, the company plans an initial capacity of 13 metric tons to lunar orbit, a spokesperson told Ars. Additionally, there will be a "growth path" to support higher future requirements, ULA's Jessica Rye said. The company plans to have this more powerful configuration of Vulcan certified for Artemis missions by 2024.

 

There are some key advantages to using the Vulcan rocket. Politically, it is considered "safe." A lunar program using a traditional aerospace contractor such as ULA is less likely to raise the ire of someone like Shelby or others, who have made no secret of their dislike for SpaceX or their mistrust of its founder, Elon Musk. ULA also has a tradition of building safe, reliable rockets.

 

But there are some potential pitfalls as well. Although ULA is relying largely on flight-proven technology for its Vulcan rocket, including the booster's second stage and much of its avionics, the rocket's first stage will use an entirely new engine built by Blue Origin. Additionally, ULA has not published prices for the Vulcan rocket, but it seems likely that the "heavy" version of the rocket with six boosters will be quite expensive, perhaps twice as much as an expendable Falcon Heavy.

New Glenn

Blue Origin, which has its own concept for the descent module portion of the lunar lander, is also building its own heavy-lift rocket. Although there has been some slippage in the schedule, this powerful booster is currently targeted for a 2021 debut. Further delays are certainly possible, as Blue Origin is attempting to scale from a New Shepard booster with about 110,000 pounds of thrust to a rocket with nearly 4 million pounds of thrust. That is a big leap.

 

In terms of capacity, the rocket's payload user's guide advertises 13.6 tons to geostationary transfer orbit. The company declined to provide an exact number for capacity to lunar orbit—understandable because without a finished rocket, such numbers are only estimates—but a capacity of 10 to 11 tons seems reasonable for New Glenn.

 

Unlike SpaceX, Blue Origin has acted more like a traditional aerospace company by forging partnerships with companies such as United Launch Alliance. It is therefore more likely that other aerospace companies would be willing to partner with Blue Origin for a ride to lunar orbit. However, it is not clear that New Glenn will have enough lift capacity to get larger lander modules to the Moon.

 

In terms of cost, Blue Origin has not published a price for New Glenn, which is designed with a fully reusable first stage. However, we would expect it to slot in somewhere higher than Falcon Heavy but lower than the heavy version of the Vulcan rocket.

Commercial SLS rocket

One option offered to contractors by NASA is a "commercial" version of the Space Launch System rocket. A fully functional SLS rocket would be more than capable for lander modules, with an estimated lift capacity of 26 tons to lunar orbit. But this option comes with some very large caveats.

 

The first caveat is scheduling. The prime contractor for the SLS rocket's core stage, Boeing, is struggling to complete production of the first core stage by the end of this year, and it will undergo a lengthy test procedure at Stennis Space Center in 2020. If those tests proceed reasonably well, the rocket will be moved to Kennedy Space Center in Florida for a launch sometime in 2021. This is probably the best-case schedule for the SLS rocket, which was originally supposed to launch two years ago.

 

NASA has booked the first three SLS launches for the Artemis program—the first mission, an uncrewed test flight; Artemis II as a crewed mission around the Moon; and Artemis III as the flight that will carry the astronauts that will land on the Moon. Based upon past performance, it is not at all clear that Boeing is up to the task of building more than three SLS core stage rockets between now and early 2024.

 

All the same, NASA says lunar lander contractors may seek an SLS rocket if they can convince the agency it won't delay their own procurement of the booster. "Any proposal that includes launching the human landing system on a commercial SLS rocket would need to demonstrate this approach does not interfere with current agency plans for SLS development, production, and operations required for the early Artemis test flights," NASA spokesperson Gina Anderson told Ars.

 

Lunar lander contractors are also on their own in terms of negotiation with SLS contractors. If a company wants to buy a commercial SLS rocket, it needs to go to Boeing, Northrop Grumman, and other large aerospace contractors involved in building the rocket to negotiate their own price. Then they need to pay someone to integrate the rocket and negotiate with NASA for use of its facilities in Louisiana, Mississippi, and Florida for a launch.

 

If all this seems like a bit of a stretch, that's because it probably is. However, it does seem possible that Boeing might pursue such an approach, with the ultimate aim of launching a fully integrated lander on a more advanced version of the SLS rocket. In any case, if NASA is truly serious about a 2024 landing on the Moon, a "commercial" SLS rocket seems like a risky and expensive choice for a lunar lander contractor.

Starship

There is one final option that theoretically could be available by 2024: the Starship vehicle under development by SpaceX. It is not clear whether NASA would even consider a Starship bid for its Artemis Program at this stage, and it's not clear whether SpaceX will bid the vehicle. (SpaceX engineers working on the Starship program were notably on the "industry day" teleconference, however).

 

If fully realized, Starship would offer NASA a revolutionary capability to not only get multiple tons of cargo to the lunar surface, but to also eventually ferry astronauts there and back. SpaceX still has a lot of development work to do to get from the prototype revealed at the end of September to an orbital version of Starship, let alone one that could land on the Moon. And the company must also complete development of its Super Heavy launch vehicle.

 

Privately, however, NASA officials are keenly aware of Starship's potential capability. If Starship is successful, it would obviate all of the other rockets above, as well as the complex two- and three-stage lunar landers NASA is seeking to develop. Starship would offer one-stop shopping for development of a lunar colony.

 

The politics of all this are messy. Certainly, mission managers at NASA would love to have such a capability. For political reasons, the agency is unlikely to be able to support the Starship program directly with more than a few small contracts. However, if Musk can find a way to get the funding needed to bring a fully functional Starship online in the next five years—a big if, to be sure—it seems likely that the above discussion will be moot as there would be one Starship to rule them all.

 

 

Source: As NASA tries to land on the Moon, it has plenty of rockets to choose from (Ars Technica)

 

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