Tiny Ion Engines could get Satellites to the Moon


Ion engines are cool. They’re a type of electrical propulsion, using magnetic fields to create engines that are a magnitude more efficient than conventional chemical rockets. A new project has miniaturized the tech so small that the engines could fit in the tiny satellites launched by college programs across the world. That project is called Microthrust.

Microthrust has already succeeded in building tiny ion engines. Their technology is there. Right now they are purely trying to refine it. Using manufacturing techniques originally meant for microprocessor development, the team has managed to make the manufacture of these diminutive engines quick and cheap.

Ion engines don’t provide a ton of force. Their beauty lies in how efficiently they produce that force. that means that an ion engine will never be used to launch from Earth’s surface. They just can’t provide that kind of thrust. But it does mean that an ion engine could accelerate a small satellite towards the moon using only a few drops of fuel.

An ion engine is basically a tube of liquid suspended near strong electrodes. The electrodes attract the liquid and it is basically sheared apart. The ions go flying towards the electrodes, which flip polarity as they go past. You might have noticed that there weren’t really any moving parts in the entire setup except for the fuel. And that is true. The engines are also basically sophisticated 3D electrical circuits, too; they can be manufactured using fairly standard and cheap techniques.

Universities around the world place experiments on small satellites that hitchhike into space with larger commercial cargo. While this is a great way to get an experiment into space for cheap, it does mean that the satellite is stuck in whatever orbit the rocket left it in. These satellites are too small to fit conventional space propulsion technologies into, so they rarely leave that orbit (except to burn up).

Those satellites, however, can suddenly go to the moon or beyond, thanks to these new engines. Using a Hohmann transfer orbit, a small university launched satellite could reach the Moon in 6 months.

Of course, these engines can do more than make science projects more portable. A contemporary of the ion engine, the hall thruster, has been used for satellite positional control in Russia since the 70’s. These tiny engines finally make ion engines, which are more efficient than hall thrusters, feasible for a similar role. And if they take off in the industry that will mean smaller, cheaper satellites which will means smaller, cheaper launches and launchers.