system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: If I was safely floating through space in a spacesuit, and a Star Destroyer closely passed by me going 99% the speed of light, would I even notice it?
gpt
It depends. If we consider it to be a perfect vacuum and the ship was just cruising through space, then probably not. However there are some other issues to consider.

If it isn't a perfect vacuum then the ship will need to push oncoming particulate out of the way or smash into it. Either way is likely to result in a sudden burst of high energy particles blasting at and likely through you. This might be noticeable as a flash in your retina, or depending on dosage maybe even heat. The suit radiation sensors would probably have a fit.