There are sightings all the time but this most recent event has skeptics thinking there might be aliens.

This video taken in July but only uploaded to YouTube yesterday shows a three lights outside of an airplane.

The lights just sit there for a while outside of the window but then seemingly start to fly out of view pretty quickly.

One YouTube comment said "Those are ducks. Ducks take on a spherical shape, and glow brightly when flying at high altitudes." That's not right, right? I've never heard anything like that before.

What do you think? Is that a UFO? Something else?