Instant landing pad

Landing on a new planet can be unsettling, but Masten Space Systems aims to put things on a firmer footing

At the start of Apollo there was huge concern and uncertainty about what kind of surface awaited. While some expected barren rock, others suggested a lunar lander might sink deeply into Moon dust. NASA sent the Surveyor probes ahead in the 1960s to characterise the surface, determining, as seen in the famous lunar landing footage, that it was somewhere between the two.

Moon dust was found to be a problem: it is fine and abrasive, a harsh glass mix that brought a burnt smell with it back into the Lunar Module. Now NASA is actively working on Project Artemis, and is closer to returning to the Moon than at any time since the end of Apollo. Along with SpaceX and Blue Origin’s commercial ventures and China’s plans for future lunar landings, we are at last likely to see the start of a moonbase in the next decade.

Such a base will need ongoing launches and landings. Longer term hard concrete landing pads will likely be cast from Moon dust, but there will be a pioneer phase when multiple craft could be scouring away dust and blasting it around the base. Large Artemis mission landers may even launch dust into lunar orbit with their rocket exhaust. The ideal situation would be for landers to bring their own pad with them, and US aerospace company Masten Space Systems is working on a concept to do just that.

Masten Space Systems was founded in 2004 and has become well known in the aerospace industry, if not to the broader public, for innovative rocket-powered landing test vehicles. In 2009 it won the $1 million (£730,000) prize at the Lunar Lander Challenge X Prize with its Xoie lander, and participated in DARPA’s XS-1 project to develop a rapidly responsive orbital launch. More recently its Xombie lander was used by the Jet Propulsion Laboratory to develop the Lander Vision System, used to fly the Perseverance rover’s skycrane as it set the rover down on Mars.

Masten has received a NASA Institute of Advanced Concepts (NIAC) grant to develop the Masten in-Flight Alumina Spray Technique (FAST) pad. In this project, Masten is studying the potential of introducing alumina, a type of aluminium oxide, into the rocket engine of a descending lander. Fired in just after the throat of the engine, the particles would partially melt, splattering over the landing site as the lander approached. As the alumina deposit cools it bonds the planetary dust together, building up a landing pad to prevent dust being blown away.

Long-standing specialists in vertical landings, Masten may be the first to put this technology into practice on the Moon with its XL-1 lander in 2022. As part of the effort to return to the Moon, NASA has established the Commercial Lunar Payload Services initiative, with a number of US aerospace companies building landers for lunar science on a commercial basis. Masten’s XL-1 lander is targeted for landing at the lunar south pole no later than December 2022.

“The ideal situation would be for landers to bring their own pad with them”

1 Rocket engine Masten has developed a range of rocket engines, and even its own self-lighting propellant, MXP-351, for use in its lunar lander. 2 Rocket nozzle The classic diverging shape of a rocket nozzle converts the stored energy of highpressure gas into kinetic energy in the exhaust stream, improving thrust. 3 Alumina particles Alumina, or aluminium oxide, is stored as pellets and injected into the hot rocket exhaust gases just after the throat of the engine. 4 Molten pellets The alumina rapidly melts in the hot gas stream and is ejected from the engine towards the landing area. 5 Alumina spray The droplets of molten aluminium oxide spray over the landing area as the lander descends. 6 Landing pad The alumina droplets join together as they cool, bonding the planetary dust before it can be blown away. 7 Masten XL-1 Masten’s lunar lander is scheduled to arrive at the Moon no later than December 2022, carrying both NASA and commercial payloads. 2 6 1 4 8 Masten engines Four of Masten’s own engines will lower the XL-1 to the surface, hopefully laying a landing pad as they do so. 5 3 9 Lunar south pole The lunar south pole is of great interest as it offers the potential of a lunar water supply and near constant solar power.

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