Japanese researchers have proposed building artificial gravity buildings on the Moon and Mars that could help reduce health risks to humans in space. Their proposals follow a study published earlier this month that found astronauts suffered significant bone loss in low-gravity environments. Japanese researchers have proposed building unveil artificial-gravity buildings on the Moon and Mars that could help reduce health risks to humans in space.

Their proposals follow a study published earlier this month that found astronauts suffered significant bone loss in low-gravity environments. Only about half of this bone loss was recovered a year after the astronauts returned to Earth, raising concerns about future missions to Mars and the Moon. Now, researchers from Kyoto University and the Kajima Corporation have proposed huge rotating structures that would create the effect of gravity similar to that of Earth through centripetal force.

They propose to build a living facility on the Moon called Lunar Glass, which will be about 400 meters tall and will complete a full rotation every 20 seconds. A similar facility called Mars Glass is proposed for Mars. Renderings of these buildings shared by the SIX Human Spaceology Center at Kyoto University are similar to the space station in the 2013 science fiction film Elysium, albeit on a much smaller scale.
The multi-story surfaces of the rotating buildings are surrounded by liquid water and tree-lined land, creating a mini-biome with water and carbohydrate cycles to support human populations.

Alongside these facilities, the researchers proposed an interplanetary transportation system that maintains Earth-like gravity along the way called the Hexatrack system. Cars of the ground-based Hexatrack train would be separated at injector stations and then inserted into a rotating hexagonal capsule that also generates centripetal force as it travels through space. Simulated rotational unveil artificial-gravity is already used in high-g centrifuges to train astronauts and aviators.

Science fiction films including Elysium, Interstellar, and 2001: A Space Odyssey feature spacecraft that rotate to create artificial gravity, although no existing spacecraft have been designed to simulate it.