These small cube-shaped objects are rocket thrusters that can be used to allow a small satellite to roll or adjust its orbit. That might not sound like a big deal but for nanosatellites, it’s huge.
The microthruster, which was developed by MIT’s Paulo Lozano, is about the same size as a penny and weighs about as much as a typical computer chip. It’s useless on Earth, but is perfectly capable of repositioning a shoebox-sized nanosatellite in the zero-gravity environment of space. The microthruster is covered with an array of 500 microscopic tips that emit tiny beams of ions when they’re stimulated by voltage.
When directed appropriately, this “small puff of charged particles” is enough to maneuver the satellite. Their tiny size makes it possible to mount several thrusters strategically around a nanosatellite to achieve a good deal of maneuverability without sacrificing valuable space.
Traditional thrusters have tended to be heavy and bulky, and thus completely unsuited to nanosatellites. Microthrusters, on the other hand, weigh next to nothing and take up a negligible amount of room. This benefits the satellite industry in two clear ways: It cuts launch weights, and allows a good deal more equipment to be packed into a nanosatellite.
While the lower launch weight translates into cheaper satellite launches, it’s the capability boost for smaller satellites that makes the technology so attractive: It allows engineers to do a lot more with a relatively tiny package.