Scientists are considering plans to mount a laser cannon on the International Space Station (ISS) for shooting down debris trapped in orbit. Space junk has been adding up in low-Earth orbit and has become a growing problem for satellites and near-Earth space missions. As the amount of orbiting space junk grows, so increases the likelihood of collisions, which can produce a cascade of other collisions in a chain reaction of debris dispersal.
NASA researchers believe that the low-Earth orbit area of space contains about 3,000 tons of debris. The debris comes from sources like defunct satellites, parts of rockets and pieces of space equipment broken off by collisions. According to Discovery News, even small pieces of debris, like screws, can cause significant damage to satellites due to their travel speeds reaching 22,370 mph.
The smallest of pieces of space debris, measuring less than a centimeter, will not cause damage to most spacecraft with shielding, including the ISS. It is estimated, however, that about 700,000 pieces larger than a centimeter are orbiting Earth right now. Pieces larger than ten centimeters are fairly easy to detect, and therefore can be dodged, but the many chunks of debris in the range of one to ten centimeters are a noteworthy cause for concern.
Some researchers are suggesting that the ISS be equipped with a laser powerful enough to shoot down space debris by disrupting the orbits of the pieces and sending them to burn up in the atmosphere. To help in spotting the debris, scientists would use the Extreme Universe Space Observatory (EUSO), which is scheduled to be installed on the ISS in 2017.
EUSO was designed to detect ultraviolet light produced by cosmic rays, but its powerful optics could also be used to spot small pieces of space debris travelling at high speeds. The pieces could then be shot at with the high-powered beam of a Coherent Amplification Network laser, which is currently under development to produce high-speed particle beams for atom smashers.
“We may finally have a way to stop the headache of rapidly growing space debris that endangers space activities,” Toshikazu Ebisuzaki of RIKEN said in a statement. “There are some technical challenges, of course, but the main issue is getting funding for development and launch.”
Researchers are hoping to install a smaller-scale debris-blasting system on the ISS as a proof of concept, and if successful, later creating a satellite dedicated to removing debris from orbit. Researchers estimate that a large-scale, debris-blasting satellite could shoot down 100,000 pieces of space junk every year.