Returning to the Moon

NASA is working to send astronauts to the Moon in the next decade, not just for short visits but to establish a long-term presence.

This time around, systems will be designed to be as reusable as possible, and NASA will look to use the Moon’s own materials for building and manufacturing.

Central to NASA’s plan is the Gateway, a space station orbiting the Moon. This will provide living quarters for astronauts making trips to the Moon’s surface. Like a highway service station, it will also allow spacecraft to be repaired and refuelled. Beyond 2030, these craft may include ones headed to Mars.

The Gateway will be manoeuvrable, allowing it to be placed in any orbit around the Moon, giving access to the whole surface.

Like the International Space Station, the Gateway will be built in space from materials ferried up in series of launches from Earth.

An artist’s concept of an Orion spacecraft.

An artist’s concept of an Orion spacecraft. Credit: NASA

Space Launch System

The Gateway’s first components will be launched on a private rocket. Later lifts will be done by the Space Launch System (SLS), NASA’s first deep-space rocket since the Saturn V that carried the Apollo astronauts. In development since 2011, the SLS is set to make its first flight in the early 2020s.

The SLS will be the most powerful rocket ever built, generating 15% more thrust than the Saturn V (8.8 million pounds, as against the Saturn V’s nominal 7.5 million pounds). In its initial configuration, the SLS will be powered by four RS-25 Space Shuttle engines and two solid booster rockets.

Boeing is the prime contractor for the SLS.

Orion crew vehicle

For crewed missions, astronauts will be carried atop the SLS in the Orion multipurpose crew vehicle. This has two parts: the crew module, which acts as the astronauts’ living quarters, and the service module, which fuels and propels the craft, and also stores water and oxygen. NASA is responsible for the crew module while the service module is being provided by the European Space Agency, ESA.

Orion is intended for use in exploring not only the Moon but also asteroids and Mars.

The Orion crew vehicle is about 50% larger than the Apollo command module and uses more advanced technology, but it contains some of the same basic design elements. The parachutes used for returning to Earth are based on those used for the Apollo program and the heat shield on the vehicle is Avcoat, first used for Apollo.

The Orion vehicle’s first test flight – uncrewed – was in 2014. The first crewed flight, a trajectory around the Moon, is currently planned for 2022.

A NASA animation showing the Space Launch System (SLS) and an Orion spacecraft. Credit: NASA