NASA has selected three companies to develop Human Landing Systems (HLS) to support future crewed moon landings. Blue Origin, Dynetics, and SpaceX will develop their designs over a ten month period, before a down-selection to one or two vehicles that will fly uncrewed demonstration missions. The Artemis III mission will then utilize one of these vehicles to land humans on the moon, as soon as 2024.
The three awarded designs are drastically different from each other, utilizing different numbers of stages and offering different balances between performance and schedule risk. Blue Origin was awarded $579 million for its design, which was associated with the least schedule risk of the three offerings. Dynetics was awarded $253 million, and SpaceX was awarded $135 million, noting that significant schedule risk was associated with the Starship system. The Starship and Dynetics designs, however, more closely resembled the sustainable, reusable capabilities NASA wishes to utilize in the long term.
Additional submissions by Boeing and Vivace Corp. were removed from consideration early in the source selection process.
Blue Origin’s National Team
Blue Origin’s proposal leverages experience from Lockheed Martin, Northrop Grumman, and Draper to produce a three stage lander. Each stage, or element, is launched separately aboard the New Glenn and Vulcan launch vehicles. The “National Team” has strong ties to both launch vehicles; New Glenn is operated by Blue Origin, and Vulcan utilizes Blue Origin’s BE-4 engine and Northrop Grumman’s GEM-63XL solid rocket boosters. Lockheed Martin is also a parent company of Vulcan’s operator, United Launch Alliance.
The Blue Origin vehicle can also be launched fully integrated aboard the Space Launch System (SLS), but there are currently no plans to make an SLS rocket available to launch HLS elements.
The lander is capable of docking either to the Lunar Gateway station or directly to the Orion spacecraft in lunar orbit. NASA Administrator Jim Bridenstine said Thursday that it is “unlikely” NASA will utilize the Gateway for initial landings.
Once the Artemis III crew transfers to the lander, the Cygnus-based Northrop Grumman Transfer Element delivers the lander to Low Lunar Orbit. From there, the Blue Origin-developed Descent Element completes the final descent to the lunar surface.
The Descent Element is powered by two Blue Origin BE-7 engines and is an adaptation of their Blue Moon lander design. Once the surface mission is complete, the Lockheed Martin Ascent Element, based on Orion spacecraft hardware, returns to either the Lunar Gateway or Orion for the crew’s return to Earth. The Ascent Element can be refueled to perform multiple ascents from the lunar surface, utilizing new transfer and descent elements.
The HLS source selection statement released by NASA outlines the methodology behind the selections of all three awardees. In selecting the Blue Origin vehicle, NASA cited a “highly effective, human-centric approach for its rendezvous, proximity operations, docking and undocking system,” resulting in reduced crew workload and improved safety. The spaceflight experience of Lockheed Martin and Northrop Grumman was also identified as a strength of the Blue Origin proposal.
Blue Origin’s proposal also meets or exceeds every single performance requirement set by NASA, including the long term goal values for future evolved, sustainable operations. Other strengths outlined in the Blue Origin proposal were a “comprehensive, detailed plan for training and certification of launch and mission operations personnel” and they plan to demonstrate the Descent Element in 2023. The uncrewed demonstration mission would land at the same landing site as selected for the 2024 crewed landing.
The only technical weakness identified by NASA is the power and propulsion system, which “has numerous attributes that introduce appreciable risk into its proposal.” However, the concern with the system was not attributed to a flawed design, but rather the reliance on an aggressive development timeline. The report concludes that this weakness does not outweigh the many strengths of the Blue Origin design.
Dynetics Human Landing System
The Dynetics HLS is a two stage design that utilizes horizontal drop tanks during descent. Dynetics plans to launch aboard a United Launch Alliance Vulcan rocket, although the design is capable of launching on multiple launch vehicles.
Like the Blue Origin proposal, the Dynetics HLS is capable of docking either to the Lunar Gateway or to Orion. The capability to abort a landing at any time during descent and the low-sitting crew cabin were highlighted as positive capabilities of the Dynetics vehicle. Dynetics also plans to conduct an uncrewed demonstration landing prior to any crewed missions.
Also, like the Blue Origin proposal, Dynetics meets or exceeds all performance requirements and goal values. But Dynetics also had a similar weakness with their power and propulsion system, demanding an “unprecedented” pace of development. The report does state, though, that Dynetics’ system is “exactly the kind of innovative solution that NASA sought through the HLS solicitation,” counterbalancing the risk associated with the system.
The Dynetics HLS is easily adapted into a large cargo delivery system, and meets or exceeds all sustainability requirements for the HLS program, and the primary element of the lander is reusable. Of the three HLS proposals selected, Dynetics earned the highest technical and management ratings.
Dynetics is partnering with several other companies to complete HLS development. Notably, the Sierra Nevada Corporation (SNC) will lead development of the crew module. SNC is leveraging lessons learned from the Commercial Resupply Services program, where they are planning to debut the Dream Chaser spacecraft next year, and their experience developing a prototype for the Lunar Gateway habitat module.
SpaceX Starship
The third vehicle selected by NASA is SpaceX’s Starship spacecraft. Starship is the only HLS selected that is fully reusable, and the only single stage design. While the Starship vehicle is not a new proposal, there appear to be new changes and details for the variant of Starship which would serve the HLS role.
A flight profile to the lunar surface would see a fuel tanker variant of Starship launched to Low Earth Orbit first, utilizing the Super Heavy booster. The crew-rated Starship would launch second, rendezvous with the tanker in order to refuel, and then perform a trans-lunar injection to lunar orbit. Like the other HLS proposals, Starship is capable of docking either to Orion or the Lunar Gateway.
While the Starship’s primary propulsion is still the Raptor engine, it would likely use a different engine to perform the final descent to the lunar surface, according to renders SpaceX shared on social media. These thrusters appear higher up on the vehicle and are likely to mitigate the potential hazards with powerful engine plumes near the lunar surface.
The renders also show a lack of aerodynamic control surfaces, meaning that the Starship would never return to land on Earth. Instead, the spacecraft would travel to and from the lunar surface many times. The vehicle offers a payload capability of up to 100 tons to the lunar surface.
Starship meets or exceeds all performance requirements, and features a significant strength in extravehicular activity (EVA) support capabilities. According to NASA’s source selection statement, Starship thoroughly addressed these requirements with an effective dust mitigation strategy and two fully redundant airlocks.
Other strengths of the Starship proposal include the immediate capability to support sustainable operations through full reusability and plans to conduct numerous ground and flight demonstrations. The Starhopper and Starship flight test campaign is already underway at SpaceX’s facility in Boca Chica, Texas, and the Raptor engine has been tested extensively on test stands in McGregor, Texas.
SpaceX plans to conduct a Low Earth Orbit demonstration of Starship and the Super Heavy booster, a reflight of a Starship vehicle, a long duration orbital Starship mission, and a flight beyond Low Earth Orbit, all prior to an uncrewed lunar landing demonstration mission in 2022. Through these flights, in-space propellant transfer between Starship vehicles would also be demonstrated.
NASA did highlight two weaknesses with SpaceX’s proposal. Starship’s propulsion systems were described as “notably complex,” and the report referred to prior delays under the Commercial Crew program and Falcon Heavy launch vehicle development as evidence for potential threats to their development schedule. However, the report also commends the rigorous testing and demonstration plans as a potential mitigation to these concerns.
NASA will monitor and review the development process of all three vehicles leading up to a down-selection in February 2021. Following the down-selection and the completion of uncrewed demonstration missions, one HLS will be chosen to land crew on the moon. This landing, no earlier than 2024, would be the Artemis III mission, following the Artemis I mission to lunar orbit with an uncrewed Orion spacecraft in 2021 and a crewed free return Artemis II mission in 2022.
The Orion spacecraft for Artemis I is undergoing launch preparations at the Kennedy Space Center, and the core stage of the SLS rocket is at the Stennis Space Center awaiting the crucial Green Run test.
