Feeling like you are being watched? It could be from a lot farther away than you think.

Astronomers took a technique used to look for life on other planets and flipped it around — so instead of looking to see what's out there, they tried to see what places could see us.

There's a lot.

Astronomers calculated that 1,715 stars in our galactic neighborhood — and hundreds of probable Earth-like planets circling those stars — have had an unobstructed view of Earth during human civilization, according to a study Wednesday in the journal Nature.

"When I look up at the sky, it looks a little bit friend...