The National Aeronautics and Space Administration (NASA) warns about the potential of orbital debris, or unusable man-made objects orbiting the Earth. Since orbital debris travels around the Earth at 17,500 miles an hour or many times the speed of a bullet, even pieces of orbital debris that are only a few centimeters in diameter can critically damage satellites and the International Space Station.
As of the present day, orbital debris has destroyed relatively few satellites. However, because orbital debris is created every time a rocket is launched into orbit (as rockets release their parts in orbit to reduce their weight) and because a satellite’s remains become orbital debris every time a satellite is destroyed by orbital debris, the amount of damage orbital debris can do to humanity’s satellite infrastructure is an ever-growing problem.
In a worst-case scenario, there may be so much orbital debris in orbit that Earth’s orbit will no longer be suitable for satellite and rocket launches. This, in turn, will mean that we will lose the many benefits satellites provide to our society including our smartphones’ telecommunications systems, GPS in airplanes, live international news, and real-time stock updates. Ultimately, in the long-term, this may result in a loss of daily luxuries people currently take for granted and billions of dollars of economic damage.
Tracking and Evading Orbital Debris
Tracking and evading pieces of orbital debris is currently NASA’s method of choice in dealing with the issue. Currently, NASA is capable of tracking and then cataloging pieces of orbital debris that are 5cm or larger in diameter in Low Earth Orbit (LEO) and 1m or larger in diameter in geosynchronous orbit. If NASA determines that there is a 1 in 10,000 chance of an orbital debris collision, it will maneuver spacecraft to avoid the debris unless this maneuver will cause additional risk to the crew.
However, this method is not sufficient to fully protect satellites and spacecraft because pieces of orbital debris that are larger than 1cm but smaller than 5cm can still damage and potentially destroy satellites, as satellites’ debris shields are only effective against pieces of orbital debris that are 1cm or smaller.
Active Removal of Debris
Although it is currently not in widespread use, active removal of debris may be the path to truly solving the issue of orbital debris in the future. Currently, only one satellite has successfully demonstrated debris-removal capabilities. In September 2018, the RemoveDEBRIS satellite successfully removed a simulated orbital debris target with a net. Likewise, in February 2019, the satellite successfully tested a harpoon-based orbital debris-removal method without creating additional debris in the harpooning process.
Other proposed methods include capturing pieces of orbital debris with magnets and even vaporizing pieces of orbital debris with space-based lasers. However, unlike the net and harpoon methods, none of these methods have been tested as of the moment.
Because orbital debris tracking technology is not sophisticated enough to truly protect satellites, our society’s best bet in saving itself from an orbital debris crisis is to have various governments and corporations collaborate in developing and deploying active removal satellites. This, in turn, will allow us to sustainably enjoy the benefits satellites provide our society for centuries to come.