Nebulae
Full Image: Mosaic of WFPC2 Pointings
July 3, 2002 · ESA/Hubble · Cassiopeia A , SNR 111.7-02.1
Glowing gaseous streamers of red, white, and blue - as well as green and pink - illuminate the heavens like Fourth of July fireworks. The colorful streamers that float across the sky in this photo taken by the NASA / ESA Hubble Space Telescope were created by the universe's biggest firecracker, the titanic supernova explosion of a massive star.
The light from the exploding star reached Earth 320 years ago. The dead star's shredded remains are called Cassiopeia A, or 'Cas A' for short. Cas A is the youngest known supernova remnant in our Milky Way Galaxy and resides 10, 000 light-years away in the constellation Cassiopeia, so the star actually blew up 10, 000 years before the light reached Earth in the late 1600s.