Okay, strange idea.
I've heard all the talk that Oumuamua, the first interstellar object ever recorded passing through our system, was an elongated asteroid or some kind of alien probe, but I had another thought. What if the object is shaped more like a normal asteroid but is passing through some kind of warp in space, making it appear elongated?
Self-contained warp, rift in space, alien spacecraft, or just an oddly-shaped space turd, I don't know. Just thought I'd vomit the idea.