Although the Hubble Telescope is set to go into retirement, NASA is still releasing stunning images from it. Recently, NASA released images of NGC 4889 (included in the picture above) -- a galaxy more than 300 million light years away. Deep within that galaxy, scientists have been able to identify a black hole that is 21 billion times the mass of our sun. To put it in perspective, the black hole in our galaxy is 4 million times the mass of our sun. Whoa.
