MIT scientists have developed penny-sized rocket thrusters that could power the world smallest satellites into space. Unlike today’s satellites, which are massive, fuel-tank-toting machines, these flat, compact alternatives look more like a computer chips.

These devices are “covered with 500 microscopic tips that, when stimulated with voltage, emit tiny beams of ions. Together, the array of spiky tips creates a small puff of charged particles that can help propel a shoebox-sized satellite forward,” reports Jennifer Chu for MIT News. This mobility gives them an advantage over other satellites, and might make it possible to quell the rapid accumulation of junk in Earth’s orbit.

Today, there are more than two dozen small satellites, called CubeSats, orbiting the Earth. These nanosatellites are cheap and easy to make. CubeSats have no propulsion system, but typically burn up as they drift toward Earth’s atmosphere. Scientists are worried that if more CubeSats are launched into higher orbits, it could take much longer for them to degrade, creating a dangerous cluster of space junk lingering in orbit.

“These satellites could stay in space forever as trash,” says Paulo Lozano, associate director of the Space Propulsion Laboratory at MIT. “This trash could collide with other satellites.… You could basically stop the Space Age with just a handful of collisions.”

With the newly developed mini-thrusters, researchers could turn these paralyzed CubeSats into nimble satellites that zoom toward this fiery fate in a more timely fashion. The new CubeSats could propel down to lower orbits to burn up, or even act as galactic garbage collectors, pulling other retired satellites down to degrade in Earth’s atmosphere.

The researchers envision a small satellite with several microthrusters, possibly oriented in different directions. When the satellite needs to propel out of orbit, onboard solar panels would temporarily activate the thrusters. In the future, Lozano predicts, microthrusters may even be used to power much larger satellites. Flat panels lined with multiple thrusters could propel a satellite through space, switching directions much like a rudder, or the tail of a fish.

Main photo credit: MIT