15 Mind-Blowing Pictures Of Space
15. Cassiopeia A
https://twitter.com/SpacePicsHQ/status/628653142612295681This psychedelic image if Cassiopeia A shows a remnant of a star that exploded 300 years previously.
Its eye-watering coat of many colours is the result of combining exposures taken across the electromagnetic spectrum and colouring them accordingly to make them visible to the naked eye.
Infrared signals are coloured red, optical data from the Hubble Space Telescope are yellow, and X-rays are coloured green and blue, giving the resultant rainbow.
The turquoise speck at the very centre of the cloud is thought to be an ultra-dense neutron star, a remnant of the massive star that created the supernova. A neutron star is one of the densest bodies in the known universe, with the mass of a who star contained in an object just a few miles across.
They're so dense that one teaspoon of material from a neutron star would be 900 times the mass of the Great Pyramid of Giza.