Supernova remnant Cassiopeia A. This is the remains of a star that exploded 325 years ago. When a large star dies, gas shells explode outwards and col

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Supernova remnant Cassiopeia A. This is the remains of a star that exploded 325 years ago. When a large star dies, gas shells explode outwards and collide with interstellar material. The energy of the collision ionises the gas, causing it to glow. Cassiopeia A lies around 10,000 light years from Earth in the constellation Cassiopeia.

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Size: 5138px × 3401px
Photo credit: © J-P METSAVAINIO/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: astronomical, astronomy, astrophysical, astrophysics, cas, cassiopeia, colour, death, expansion, explosion, gas, natural, remnant, shell, shells, snr, space, star, stellar, supernova, telescope, young