If you've got a telescope looking at some distant star (I'm talking one of the millions you can't see with the naked eye) and suddenly it goes dim like something's in the way, it might be because something's in the way. Then you just track the occlusion of other cosmological objects around it to see if there's actually an object there.
Occlusion.
If you've got a telescope looking at some distant star (I'm talking one of the millions you can't see with the naked eye) and suddenly it goes dim like something's in the way, it might be because something's in the way. Then you just track the occlusion of other cosmological objects around it to see if there's actually an object there.
blink comparator, yes?