There is indirect and rather

Forums Comets C/2017 U1 (PANSTARRS). An interstellar comet? There is indirect and rather

#578674
Nick James
Participant

There is indirect and rather weak evidence that some other objects may have interstellar origins but A/2017 U1 (now demoted from cometary status) has direct evidence from its strongly hyperbolic orbit. We’ve never seen anything with this kind of orbit before.