An infant neutron star, the super-dense core of a stellar explosion, has been observed for the first time. The 12.4 mile-wide object is the youngest object of its kind ever discovered, having appeared just 330 years ago.
It has been cloaked in mystery since it was identified as a powerful X-ray source in 1999. Astronomers now know the source is a neutron star 11,000 light years from Earth at the centre of the supernova Cassiopeia A.
The newly identified neutron star has a unique carbon atmosphere just four inches thick.
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