The Moon is covered with regolith, a layer of crushed, sharp rock that could pose a threat to future landing missions by damaging spacecraft and putting astronauts in danger. While major industry players are hard at work with designing more durable and efficient wheeled rovers, MIT engineers propose a solution that doesn’t even imply touching the Moon surface.
MIT is working on designing a vehicle that can levitate above the rugged lunar terrain. How? The engineers say that it can be done by using the Moon’s “natural charge.” This natural charge refers to an electric shell that forms on celestial bodies that lack an atmosphere, like our Moon or asteroids, for example. Since they don’t have an atmosphere, the sunlight hits their surface without being held back by any other additional gases. On our Moon, this causes the dust to get electrostatically charged by the Sun and actually lift-off for more than 1 meter (3,2 ft) above the ground. The effect is similar to when you rub a balloon to your hair then slowly move it away. The vehicle proposed by MIT makes use of this positively charged surface. More specifically, it uses ion thrusters to generate a repulsive force that should be just enough to make an almost 1-kg (2-lbs) vehicle levitate on the Moon. The thrusters would serve the purpose of charging it as well. To put their concept into practice, scientists first created a small saucer-like vehicle with thrusters that beamed negative ions out, giving the vehicle itself a positive charge and directing its force against the lunar surface. However, that wasn’t enough to make it go up. Then they added some thrusters that generated positive ions to boost the natural charge. Using a 50-kilovolt source and this second model, the engineers calculated that a small vehicle could lift off 1 centimeter (0,39 in) above the ground. Of course, the higher the voltage, the more force produced. “In principle, with better modeling, we could levitate to much higher heights,” aerospace engineer Paulo Lozano says.
This is just the foundation for a more complex design. However, if successful, future missions to the Moon and asteroids could use rovers with ion thrusters to safely navigate across the rugged terrain.
Keyword: Forget About Wheeled Rovers, MIT Is Working on Vehicles That Use the Moon to Levitate