Russian cosmonaut spots 'space guests'.

Russian cosmonaut Ivan Vagner has captured some astonishing glimpses of Earth from above as seen from the International Space Station, but his latest video of auroras included a surprise: five bright lights on the horizon that he entitled 'space guests.'

They're plausible satellites, not aliens, but still amazing to see for sure. The most likely culprit is the Starlink broadband satellites SpaceX launched on Tuesday (Aug. 18), a day before Vagner shared his video, although that has not yet been verified.

"In the video, you will see something else, not only the aurora," Vagner said on Twitter. Indeed, at the 9- to the 12-second mark, a group of lights quickly shows in the video before disappearing.