Lunar space elevator moon base. Artwork of a future lunar space elevator at its base on the near side of the Moon. The support facilities include a loading machine (yellow, with cargo boxes), and astronauts. The lunar space elevator (around 50 metres long) has a solar-powered climber mechanism (solar panels, blue) that uses caterpillar track treads to pull the spacecraft along a ribbon running from the surface to a Lagrange point. The journey takes over 3 weeks at 100 kilometres per hour over a distance of around 56,500 kilometres. The crew compartment is at lower left. Cargo arrays are either side of the climber mechanism.