It can get crowded in orbit. New satellites and spacecraft launch every year, while old ones collect around Earth, increasing the chances of unfortunate collisions.
Bigelow Aerospace's Genesis II, an inflatable space habitat test mission that launched in 2007, has a 5.6% chance of colliding with the dead Kosmos 1300 satellite early on Wednesday. That's enough of a chance to cause worry.
"Although this is a relatively low probability, it brings to light that low Earth orbit is becoming increasingly more littered," Bigelow tweeted on Tuesday, saying the US Air Force alerted it to the issue.
Neither Genesis II nor the Russian satellite, which was launched all the way back in 1981, are capable of being moved within their orbital paths to avoid a crash. They are both examples of orbital debris at this point.
Bigelow was able to maintain communication with the test spacecraft for two years, but the test habitat is slowly and quietly working its way back toward Earth, where it's expected to eventually burn up in the atmosphere.
Bigelow followed up its initial tweet by saying, "Future habitable space stations will face this reality and danger. This proliferation, if not controlled in number, could become very dangerous to human life in low Earth orbit."