Earth’s orbit is becoming something of a teenager’s bedroom: There’s junk scattered about and no real plan to clean it up any time soon. The critical difference? The consequences of space junk go well beyond pests attracted by crumbs or the odor of unwashed laundry.
For decades, experts have been warning about the rise of space junk in Earth’s orbit. In the Space Age, there have been thousands of rocket and satellite launches, and not everything that goes up into orbit comes back down. (And as the Chinese space program recently reminded us, falling debris can also be concerning if improperly handled.) Now, thousands of dead satellites and thousands more small pieces of junk remain circling Earth—all of which pose a significant threat to space infrastructure and could inadvertently take down satellite arrays if poorly managed.
Recently the problem has been getting worse.
Even objects just centimeters in size pose grave threats given the speed of objects maintaining orbit and the difficulty in tracking smaller pieces of junk. What was likely a speck of paint chipped multiple layers of the ISS’s Cupola window back in 2016. It turns out that pretty much anything can be dangerous if it smacks into you at approximately 17,150 miles per hour.
Efforts to properly dispose of rockets and orbiters—like lowering the perigee (basically the point closest to Earth) of objects’ orbits through propulsion burns to allow for controlled burn-up upon atmospheric re-entry—could help to mitigate the growth of space junk. But very few actors have worked toward cleaning up existing junk. In fact, to date no space organization has successfully captured and disposed of an “uncooperative” object in orbit (that is, one in an unstable rotation). Current methods of orbital capture usually require intense control of both the capturer and the target object.
Thankfully, the European Space Agency is trying to establish a new scientific precedent with its ClearSpace-1 Mission. The mission—formally announced in late 2020 in collaboration with ClearSpace SA—will launch in 2025 in an attempt to use an experimental capture system to remove a Vega Secondary Payload Adapter still in orbit from a 2013 mission. To that end, the ClearSpace start-up has recently founded a U.K. subsidiary to oversee the mission.
This is not the ESA’s first attempt to clean up space junk. It also funded the 2018 RemoveDEBRIS test of a net apparatus, but it didn’t actually clean up real space junk due to property rights under international law that states anything sent into orbit remains the property of the nation who launched it. The new effort is working to clean-up existing space debris, and since the ESA owns some space junk the ClearSpace-1 mission has the legal authority to do so. However, it is a relatively small and easy target to start the ESA’s efforts, as the VSPA is nothing compared with the double-decker bus-sized Envisat which the ESA lost contact with in 2012.
Recently, private industry has undertaken missions to tackle space junk, but in fairly limited ways. In March, the Japanese-U.K aerospace company Astroscale launched ELSA-d, whose mission is to track a dummy satellite and eventually dispose of it. NEO-01, launched by Shenzen startup Origin Space in late April, intends to capture space junk via net and burn it through use of its propulsion system. ELSA-d, while great in theory, uses a magnetic system that could not be deployed on current junk—only to remove future satellites outfitted with the magnetic docking system from orbit. And NEO-01’s net technology would be used predominantly for space mining operations—not orbital cleanup.
Decluttering space will require much more. So, space organizations—both commercial and national—need to join efforts to finally clean up their proverbial room of orbit. At the national level, major contributors to existing space junk like Russia, the United States, and China need to do more work including waste disposal missions of their own. Especially given the millions of dollars these projects will cost, international collaboration is a must. This collaboration must also include new diplomatic agreements banning the intentional detonation of satellites and other objects in orbit—something both China and India have done in the past. These in-orbit explosions only multiply the number of pieces of space junk that existing satellite arrays must contend with.
At the corporate level, governments need to introduce market incentives for companies to clean up and minimize their contributions to space junk as well. This could take the form of financial responsibility for satellite accidents or annual fees for orbital use. Simply put, companies are not concerned with the costs their satellites impose upon space as a common resource. Without these incentives and renewed interest from international leaders in space exploration, space junk will continue to fester.