Space Junk, debris left over by dead satellites, is a problem that space experts have been discussing for decades but have not yet managed to implement a solution to. Junk ranging from tiny particles to intact satellites hurtled about as fast as 22,000 an hour, creating a hazard to space navigation and placing functioning space assets at risk.

One solution that keeps coming up is using lasers to zap space junk, causing it to slow down and fall out of orbit, burning up harmlessly in the Earth’s atmosphere. A group of Chinese researchers has proposed just such a system in the journal Optik.

However, the idea of setting up laser battle stations in orbit makes military experts nervous. The same lasers that can deorbit space junk can do the same to functioning satellites.

How lasers in orbit can be a potent weapon.

The idea of space-based lasers has been around at least since President Reagan’s SDI proposal. In the Strategic Defense Initiative proposal, lasers could be used to shoot down enemy missiles as they fly from enemy silos to destroy cities and military targets with nuclear weapons. Lasers could also be used to remove military satellites that provide communications, navigation, and reconnaissance services to the military. The result of a “space Pearl Harbor” could be catastrophic.

Warfighting would be back to the technology of World War II.

How to remove space debris without risk of war.

The deployment of space-based lasers, even if said for benign purposes, would likely not be looked upon with favor by an opposing nation. The United States, Russia, and China are all working on space-based weapons designed to take out the orbiting assets of a potential enemy.

The Chinese have tested rudimentary weapons to destroy their own satellites, causing nervousness at the Pentagon. If China or Russia were to actually deploy laser battle stations, that agitation would escalate to full-scale panic. Both of those countries would be triggered by an American deployment of lasers in space as well.

Clearly, if lasers are to be used to start cleaning up space junk, the effort had to be a joint one, with every side in control of the process so that confidence could be built that the lasers will not become warfighting assets. The laser satellites would have to have a fail-safe mechanism to prevent them from being used for anything but debris removal.

The United States has been reluctant to cooperate with China in space because of that country’s imperialist drive on Earth and suspicions that the Chinese are bent on stealing American technology. However, the growing necessity to remove space junk may give both countries no choice.