If you saw the blockbuster Gravity, then you probably had the dangers of orbiting space debris impressed upon you by a 90-minute emotional Hollywood roller coaster. While such catastrophic events haven’t ever happened, the risks of in-space collisions are certainly very real. In 2009, two satellites collided and rapidly produced thousands of smaller orbiting objects. It is this high production of smaller material from a single collision that can precipitate a snowball effect of increased collision rates and exponential debris production that would endanger both current and future space missions. While preventing encounters with the thousands of already orbiting small debris objects may be a relatively intractable problem, preventing the high production of debris from larger objects certainly isn’t.
To this end, a UK-led effort to remove these large, dead satellites has begun a series of proof-of-concept tests this month. A consortium of 10 companies and the European Commission have funded RemoveDEBRIS, a harpoon-wielding, garbage-net-throwing prototype satellite. The first test was successfully executed this past weekend by launching a net around a 1-meter-wide balloon to simulate grabbing debris. The second method for grabbing the space junk will involve firing a harpoon at a target. After tethering the junk to the RemoveDEBRIS satellite, the final step will use an expandable sail to bring the space trash and RemoveDEBRIS back into the Earth’s atmosphere. The heat from re-entering the earth’s atmosphere will burn up the trash, preventing it from impacting with Earth’s surface.
Assuming these tests succeed, the prototype’s main accomplishment is its demonstration of these methods at a relatively low cost of about $17-million – 1 ten thousandth of the cost of the International Space Station (ISS) alone. “There will always be a tension between letting debris stay as it is or [the cost] of going to clean up some of it,” says Aglietti, the principal investigator of the project. Proving that removing space junk is an affordable enterprise was the first barrier to overcome before we can reach the ultimate goal of preventing debris-caused collisions.
Managing Correspondent: Matthew Rispoli