That Interstellar Asteroid is Pretty Strange. Could It Be...?

It isn't aliens. It's never aliens. That's the only sensible answer whenever astronomers spot something truly weird in space. That unusual radio blip from the planet Ross 128b? Not aliens. Potential SETI signal SHGb02+14a? Not aliens. The mysterious 'alien megastructure' star? Probably not aliens, either. There are so many unexplored natural explanations for unusual phenomena, and so many ways to make errors, that the starting assumption has to be no, no, a thousand times no, it is not al