A New Ion-Thruster Concept Could Make Space Habitable for Satellites Again

A diagram and proof of concept photos of the ion-thruster that will clear low-earth-orbit of space junk. (Image courtesy of Kazunori Takahashi.)

Engineers from Tohoku University in Japan and the Australian National University have developed a space-based plasma beam cannon that will help remove the wall of satellite debris orbiting Earth.

For the past decade, researchers around the world have become increasingly concerned with the amount of debris cluttering access to space. All told, researchers have identified more than 7,000 man-made objects floating around in space, just above Earth’s atmosphere. Each of these objects—whether spent rocket boosters, decrepit satellites or micro-objects—represent a danger to new satellites being placed in orbit. With space being targeted as a frontier by pioneering nations like the U.S. and Russia, and newcomers to the off-world scene, it’s more important than ever to ensure that expensive satellites are not torn apart by space-junk during their operational life.

To solve this space junk problem, a number of solutions have been developed. This new idea might be the best solution yet.

As reported by Tohoku University, the joint Japanese-Australian solution proposes that a satellite be sent into space carrying an ion-thruster. It could be used to slow down space debris so that the target debris slowly falls towards Earth, eventually burning up in its atmosphere during re-entry.

What’s most interesting about this new space debris eliminator is that it takes into account Newton’s third law: For every action there is an equal and opposite reaction.

Pretty critical, right?

To make their junk destroyer work, the satellite would have two plasma thrusters mounted on opposing sides of its body. Once the satellite locked onto a targeted piece of debris, both ion cannons would fire. One cannon would be fixed on the target object. The other would fire in the opposite direction to hold the ion-cannon satellite in place.

“This discovery is considerably different to existing solutions and will make a substantial contribution to future sustainable human activity in space,” said Associate Professor Kazunori Takahashi of Tohoku University.

Although this new concept could make space more habitable, and useful ground for civilian satellites, it has other potential applications. It hardly takes a wild imagination to think the concept could be used for covert offensive operations meant to critically destabilize off-world communication infrastructure if a conflict between space-faring nations ever escalated to the point of war.

Still, a technology like the ion-thruster space-junk eliminator is becoming more important every year. Whether the technology will be militarized—if it hasn't already been invented and deployed in secret by a black-ops program—shouldn’t stop the deployment of a constellation of satellites of its type. Our path to the moon, Mars and stars beyond our solar system may depend on this critical tech.