According to NASA, the most intriguing and distinctive features are boulders that dot the surface of the comet. Despite NASA’s explanation that the most UFO-like objects are just boulders, this object doesn’t really look like a rock.
Besides, there are some other strange objects found on the comet (see video) which cannot be characterized as just boulders, suggest that comet 67P may hold alien life.
However, scientists have dismissed claims that the Rosetta comet could harbour alien life.
If the comet is not an ancient alien spacecraft and it is too inhospitable for life then explain the strange unnatural objects and a UFO on the surface of the comet.