Animation showing the expected and measured trajectory of `Oumuamua

This animation shows the path of the interstellar object `Oumuamua through the Solar System. Recent measurements of `Oumuamuas flight path show that it is not moving as the laws of celestial mechanics predict — its course is slightly off.

Researchers assume that venting material from its surface due to solar heating is responsible for this behaviour. As outgassing is a behaviour typical for comets, the team thinks that `Oumuamua’s has to be classified as interstellar comet.