Eliminating Space Debris with Ground-Based Lasers
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Australia’s EOS Space and Japan’s EX-Fusion combat space debris with a laser system, which could be a crucial fix for the increasingly crowded Earth orbit.
Space debris is defunct human-made objects (like old satellites and spent rocket stages) floating in Earth’s orbit that pose collision risks to operational spacecraft and the International Space Station. Even debris the size of a few millimeters can create problems when it hits functioning satellites and spaceships.
As space-related activities spread globally, this issue becomes more and more urgent, and many countries are already working on it. Examples include the Tokyo-based Astroscale Holdings which plans to launch a dedicated satellite to remove large space debris, or Japan’s Sky Perfect JSAT, which is developing a satellite-mounted laser that redirects space debris into the Earth’s atmosphere to burn.
According to Interesting Engineering, EX-Fusion stands out for taking a ground-based approach. The company will collaborate with the Australian EOS Space Systems, which has technology for detecting space debris.
The initial stage of this project will reportedly involve setting up laser technology to track space debris sized under 10 cm, a size that has been traditionally challenging to target from the ground using lasers. For the second phase, the two companies will use laser beams fired from the surface to remove space debris.
It works by intermittently firing the laser in the opposite direction the debris is traveling to slow it down, and the decrease in orbiting speed should cause the debris to enter the Earth’s atmosphere where it will burn up.
The lasers designed to remove space debris are different from weapon-grade lasers- while current laser weapons use fiber lasers to cut, weld metal, and destroy drones through continuous firing heat, EX-Fusion’s method will use diode-pumped solid-state (DPSS) lasers. These lasers are pulsed to apply force to fast-moving debris, essentially stopping it like a brake.
This ambitious plan is currently facing development hurdles regarding precision and power, but it still has the advantage of allowing for improvements and maintenance to be easily handled on Earth. The technology could potentially be used alongside space-based debris removal services.
