The moon and many similar or smaller bodies lack atmosphere. The incident solar radiation, in cooperation with the surrounding plasma, generates an electric field on such bodies. For example, on the Moon, the surface electric charge is so strong that the moon’s dust can levitate more than one meter above the surface itself. It’s like static electricity running through your hair.
Recently, American engineers have been trying to use this natural electric charge of the Moon and other bodies to power remarkable machines that would hover above their surface. These machines should be made of Mylar, a polyester film that tends to have the same electric charge as the surfaces of these bodies.
On smaller bodies, such as smaller asteroids, repulsion of electrical forces alone should be enough to hover. However, larger bodies complicate such a movement with too much gravitational attraction.
The Massachusetts Institute of Technology (MIT) team creates a flying “retro” rover in the form of a “flying saucer”. Their machine not only floats, but also uses small currents of ions, which amplify the electric charge of the rover itself and locally the charge of the body surface above which such a rover should levitate. The result is a relatively large repulsive force with only a very small amount of energy.
The first feasibility studies show that a rover of this type with the mentioned ion “propulsion” should be able to move on the Moon and large asteroids, such as Psyche in the main belt of asteroids.
As Oliver Jia-Richards, head of “flying saucer” development, mentions, similar flying rovers should be used on missions such as the Japanese Hajabusa spacecraft expedition to Itokawa. Future probes could launch flying rovers that are more likely to be able to explore a larger area of the body than if they were traveling on its surface.
The big advantage is that with a levitating rover, operators and technicians don’t have to worry about wheels and other moving parts, which are a common source of problems. Another thing is that the surface of the studied asteroid can be very complicated, but the flying rover should not surprise it.