If astronauts are ever going to work on asteroids scientists first have to overcome a major obstacle - very low gravity. The minimal gravitational force of even a large asteroid is not enough to prevent an astronaut from bouncing away from it and into space. Obviously exploratory activities such as excavation and drilling are almost impossible under such conditions. In the movie Armageddon the problem was solved by the astronauts' rocket-assisted space suits, perhaps not the most energy efficient idea.

So two scientists at the Massachusetts Institute of Technology have come up with their design to tackle this problem. Looking like a cross between a weird cable car and a baby bouncer. Two bands of a tough polymer ribbon are wrapped around the asteroid about two metres apart. They are laid by an unscrewed space vehicle controlled from a nearby spacecraft. The ends of the ribbons are held taut by a motorised mechanism.

The astronaut wears a harness attached to a frame from which four arms project. The arms clip onto the ribbons, which exert a downward force to anchor the astronaut but allow movement along the direction of the cable ‘track'.

The design may be trialled sooner than you think as NASA may initiate manned asteroid missions to provide a testbed for any future Mars trip. The technology for the asteroid harness is all available today, including the super strong polymer for the ribbon.