Galaxies After the Andromeda and Milky Way galaxies finish merging in a few billion years, what will happen to the other galaxies in the Local Group?
Science What would we see if the solar system were located in a dark nebula like the Coal Sack? Would things look much different from inside a bright nebula such as the Orion?
Stars I’ve read about stellar explosions propagating at “supersonic speed.” On Earth, supersonic means faster than the speed of sound. How does this idea apply to stars?
