Who said anything about aliens?
Settle down.
Dr. Abraham "Avi" Loeb, Director of Harvard's Institute for Theory and Computation.
Haaaaaaavard, go figure.
Another PhD proving it's
Piled higher & Deeper
Meanwhile, back in the real universe......
Most of the known comets come from the Oort Cloud, on the outskirts of our Solar System.
Anything traveling as fast as comet 3I/Atlas is from outside of our general area. It will travel around the Sun, and head out to the great beyond, and probably be captured gravitationally by another system, someday.