Current speculation is that it's a novel object type, unlike the conglomerate iceballs we call "comets," with a different origin and history. Unfortunately we

Current speculation is that it's a novel object type, unlike the conglomerate iceballs we call "comets," with a different origin and history. Unfortunately we did not make the heroic effort it would have taken to get a close look, so as with 1I/ʻOUMUAMUA we'll be left with enigmas and uncertainty. Unless of course it brakes hard into a parking orbit. :)