Alles, was man gerne von Borisov (weniger berühmt und weniger zigarrenförmig als der erste interstellare Eindringling, ʻOumuamua), wissen würde, u.a.: kommt er wirklich aus einem anderen Sonnensystem?

„[S]ix suggestions have been made as to how this might be something else. Four of them are quite definitely wrong. The other two would be really unlikely.
So this object almost certainly got sent to us long, long ago, from a star far, far away. (But as stated above, not from a galaxy far, far away.)“