Space isn't always so spacious. Russian cosmonaut Oleg Artemyev gave us a reminder of the existence of space traffic with a video tweeted Wednesday showing a satellite flying by the ISS.
The satellite shows up well against the background of Earth's blue water and white clouds. Artemyev zooms in to give a better look at the blocky machine. You even make out details of its solar panels. It looks like a mini version of a Borg cube spaceship from Star Trek.
Artemyev doesn't say which satellite it is, but it appears to be the RemoveDebris spacecraft, which was just launched into orbit from the ISS Wednesday. That's why Artemyev was able to track it so cleanly and closely on video.
RemoveDebris is set to demonstrate technology related to clearing up space debris in orbit, including a net and a harpoon designed to capture debris.
NASA estimates there are more than 500,000 pieces of space junk clogging up orbital paths around Earth. The International Space Station is heavily shielded, but can also maneuver to avoid collisions with space debris.
The ISS can't always get out of the way. ESA astronaut Tim Peake shared a photo of a space station window in 2016 showing a small chip caused by debris impact, but it posed no threat to the ISS.