September 15
Center of the Crab Nebula
Observed in 2005
At the center of the Crab Nebula sits a stellar remnant called a neutron star that has about the same mass as the Sun compressed into a sphere only a few miles across. Spinning 30 times a second, the neutron star shoots out beams of energy that make it look like it's pulsating.
Image credit: NASA, ESA, Hubble Space Telescope