A Space Age "disaster of the commons" is unfolding right under our nose — or, really, right over our head. For more than half a century, humans have been casting objects into low-Earth orbit in ever growing numbers. And with few meaningful limitations on further launches, the general attitude has been permissive: in orbit, it seems, there is always room for one more.
After so many decades of the build-up of high-speed chaos in the form of spent rocket stages, low-Earth orbit is finally on the edge of becoming too crowded for comfort. And the problem tends to get much worse because of the rise of satellite "mega constellations (大星座)" requiring thousands of aircraft, such as SpaceX's Starlink. Starlink is but one of many similar projects. Another mega constellation from a company called OneWeb is already being stationed. And Amazon's Project Kuiper is seeking to create a mega constellation of up to 3,200 satellites in the near future.
The International Space Station regularly adjusts its orbit to avoid potentially risky debris (碎片). Worse yet, there has been an increase in the threat of full-on collisions. Consider the February 2009 run-in between a dead Russian satellite and a commercial aircraft, which produced a great amount of debris.
Finding ways to remove at least some of all that space rubbish should be a top global priority (优先), says Donald Kessler, a scientist for orbital debris research. In the late 1970s, he foretold the possibility of the Kessler conditions: as the mass of space trash increases, self-protecting runaway cycle of debris-generating collisions can arise, making low-Earth orbit too risky to support most space activities.
"There is now agreement within the community that the debris environment has reached a 'tipping point' where debris would continue to increase even if all launches were stopped," Kessler says. "There are collisions taking place all the time — less noticeable and not in large numbers," Kessler adds.
