Coordinates in the Sky "The purpose is to be able to uniquely specify a location in the sky. It's just like latitude and longitude on Earth," Rick Fienberg, press officer for the American Astronomical Society, explains in an email. "If you tell someone to meet you in Littleton, Colorado, at 39°36'47.9484''N, 105°0'59.9292''W they will not only know which town you're in but also which street corner you're waiting at.... It wouldn't be very useful to someone else to know only which town you're in — you need to be more precise if you have any hope of being found by the other person." … [Read more...] about How Do We Find Things in the Blackness of Space?