The NASA/ESA Hubble Space Telescope has unveiled a stunning image of the Abell 209 galaxy cluster, located 2.8 billion ...

Imagine waking up one morning to the news: a black hole is drifting close to our solar system. It sounds like the plot of a .

Quasar 0957+561, the first known gravitationally lensed quasar, lies near NGC 3079 in Ursa Major. Here's how to find and ...