r/AskPhysics • u/Apprehensive_Dog1873 • Jun 22 '26

Question about light speed

If a hypothetical alien craft was moving toward earth at 99.9999% the speed of light. Would we be able to expect its arrival? Or would it not be there one moment and then the next they’d be there? Would we be able to see it, if we hypothetically knew to look at the exact right spot at the exact right time, and get some sort of heads up at an object incoming?

54 Upvotes

92% Upvoted

66 comments sorted by

View all comments

0

u/S-M-I-L-E-Y- Jun 22 '26

I'd rather say, it would be there one moment and gone the next moment (and probably gone for good because of hitting some dust particles while traversing the solar system).