Experts see 'youngest' neutron star

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Astronomers have observed the youngest known neutron star - the super-dense core of a stellar explosion - for the first time.

In 1999, they identified the 12.4 mile-wide object as a powerful X-ray source. Now they have identified it as an infant neutron star 11,000 light years from Earth in the middle of the supernova Cassiopeia A.

Having appeared only 330 years ago, it is the youngest object of its kind to have been discovered. All other known neutron stars are much older.

A neutron star is the very dense compact centre left after huge conventional star disintegrates in a violent explosion at the end of its life.

What remains is composed almost entirely of neutrons - sub-atomic particles without an electric charge - compressed tightly by gravity.

Professor Craig Heinke, from the University of Alberta in Canada, who co-led the new research published in the journal Nature, said: "This neutron star was born so hot that nuclear fusion happened on its surface, producing a carbon atmosphere just 10 centimetres thick."

John Flamsteed, Britain's first Astronomer Royal, is thought to have observed the supernova that created it in 1680.

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