Startup Building Huge Laser to Shoot Down Space Junk From the Ground

Target acquired.

Fusion Cuisine

A Japanese startup called EX-Fusion has announced a bold new plan to take out space junk: shooting the stuff down with laser beams, Nikkei Asia reports. The experimental technology could be one of many potential methods to tackle the daunting task of cleaning up our planet's cluttered orbit.

Rest assured, this approach doesn't involve blowing stuff up in space. Instead, the startup will use a type of beam known as diode-pumped solid-state laser to nudge debris out of orbit and into a safe area of the Earth's atmosphere, where the debris will burn up upon re-entry.

It's not the only company pursuing a laser-based approach, but unlike some of its competitors, EX-Fusion says its method will be ground-based, rather than relying on lasers mounted on satellites. The startup also has a curious potential edge: a background in exploring nuclear fusion, for which its lasers were originally designed.

"The power of a laser for destroying space junk is an order of magnitude lower than for nuclear fusion, but they share technical challenges such as controlling them via special mirrors," EX-Fusion CEO Kazuki Matsuo told Nikkei.

Laser Focus

The first phase of the EX-Fusion's plan will involve installing its laser at an observatory in Canberra operated by the Australian firm EOS Space. Things are already moving along, with the two companies signing a memorandum of understanding in October last year, Nikkei reported. The goal is to set up a less powerful iteration of the laser that will track space junk that's smaller than four inches, a size that has proved difficult for other ground-based lasers to keep tabs on.

The second phase is when the laser will be powered up to take down a selected target. It will be shot intermittently so that the beam pushes against the direction a piece of space debris is traveling in. Once slowed down, the reasoning goes, the debris should fall into the atmosphere.

It may sound a little far-fetched — and indeed, the timeline for EX-Fusion's plans is unclear — but NASA has already acknowledged the broader technology's potential in a report last year, noting both the usefulness of a ground-based approach and a space-based one, though not favoring one over the other.

Garbage Man

Whatever ends up being the best method — and it will likely end up being several used together — NASA as well as the European Space Agency have been clear that space junk is already a serious issue.

Astronauts face the most immediate threat. The International Space Station has been forced to dodge debris on numerous occasions. In the future, the junk could crowd out new satellites from being stationed, block space travel, and uncontrollably fall to Earth.

For now, clean-up efforts are rocky and difficult. A ground-based approach could potentially be less messy than sending junk-hunting space probes to handle the task — that is, if the idea ever gets off the ground.

More on space junk: FAA Warns That Falling Satellites Are Going to Start Killing People