Ants were originally of extraterrestrial origin.

Only three of the characters are involved in a plot that can lead to various endings, involving a supernatural object of extraterrestrial origin.

On further exploration, the team discovers a mysterious spherical artifact, clearly of extraterrestrial origin, which quickly becomes the focus of their attention.

Historically, observed falls were the most compelling evidence supporting the extraterrestrial origin of meteorites.

Extraterrestrial origin was first proposed in 1979, but not until 1993 was the impact structure finally confirmed.