How dense is a black hole? Mind blowing space facts about the Universe for astronomy / astrophysics fans! Also make sure to visit www.kidsinorbit.com - Learn how to become an astronaut! 100% dedicated to kids science / astronomy! Image: NASA Earth Observatory images by Robert Simmon, using Suomi NPP VIIRS data from Chris Elvidge (NOAA National Geophysical Data Center).
13 months ago