The NASA space scientists have come up with a solution to deal with the issue. This will be done by nudging space junk off collision pathways using mid-powered lasers. 20,000 pieces of junk consisting of bits of spacecrafts or fragments from collisions have been tracked in low-Earth orbit by the U.S. military.
A significant part of this junk is pulled down by the atmosphere to Earth every year. In 1978, Don Kessler an astronomer foresaw a doomsday case where debris is likely to increase as a result of collisions. He went further to say that it will reach a point where the junk will be increasing faster than they can fall out of the sky. This will create a permanent junk belt that can pose a dangerous situation and it was named as “Kessler syndrome”.
Such a case was observed in 2009 by the collision of two communication satellites plus other scary smashes and near-misses. The International Space Station was nearly affected by the debris from that collision. Some researches done have confirmed that the Kessler syndrome is underway and likely to happen. Creon Levit, a NASA engineer points out that things are getting worse and it is going to screw up everything unless something is done.
A NASA team led by James Mason also suggested in a paper submitted to Advances in Space Research that the best way to cope with the situation was to stop the collisions. One of the team members, William Marshall, a space scientist at NASA says that if the collisions are stopped, the atmosphere will naturally start to drag things down. This will involve stopping any new debris from forming as said by Levit.
The atmosphere can only drag the flattest and light pieces that have more area first than the smaller ones. When a big rock of debris breaks up into smaller pieces, the smaller pieces harden so much that it is too difficult to remove these pieces. Furthermore, the smaller debris is the most dangerous as they move at an unreasonable relative velocity of 5 miles per second and if they collide with a satellite it will be completely destroyed.
There was a plan to shoot space junk with laser before, but they relied on military-class lasers earlier. Not only are these military-class lasers expensive, they also instigate fear in other space-faring nations because they are not sure who the laser is pointing at, the debris or others’ satellites.
The alternative laser to be used is the type used for welding and cutting, which costs about 0.8 million dollar plus a bit more of tens of millions of dollars for the remaining part of the system. The cost depends on whether they are going to rebuild it or just revamp an already used telescope like the one that is used at Air Force Maui Optical Station in Hawaii. All said, a space security expert points out that this will only be a temporary solution and it will not remove the debris completely or stop the new junk from forming.
Source : Wired Photo by : Science Photo Library