EARTH SIZED DIAMOND..

 

Astronomers discover coldest ever white dwarf - an ancient diamond the size of the Earth

Astronomers have identified what might be one of the strangest stars in our galaxy: an incredibly cold, ancient and faint white dwarf that has crystallized into a diamond the size of Earth.

White dwarfs are stars at the end of their life span when the fusion reaction that has pumped out heat and energy during has all but stopped, leaving the remaining carbon and oxygen to compact into an incredibly dense and cold state.

In the case of this recently discovered white dwarf, astronomers believe that it has cooled and crystallized all the way to diamond, estimating that the once-fiery star is 11 billion years old – making it the same age as the Milky Way.

Stars like this aren’t rare (around 97 per cent of stars are thought to turn into white dwarfs and they've even discovered planets made of diamond) but they are incredibly difficult to find – simply because their light is too faint to make its way through the cosmos to telescopes on Earth.

Thankfully, this particular white dwarf had a partner that gave away its presence to astronomers on Earth: a companion pulsar star dubbed PSR J2222-0137.

Pulsars are super dense neutron stars that spin incredibly quickly, shooting beams of radio waves into the cosmos like supercharged lighthouses. However, with PSR J2222-0137 astronomers noticed that the radio beams were regularly obstructed by an unknown object.

The team from the National Radio Astronomy Observatory in the US suspected it was a white dwarf, but were still unable to see the object after further observation. They explained that this is one of the coldest white dwarf ever discovered.

Carolina graduate student Bart Dunlap. “If there's a white dwarf there, and there almost certainly is, it must be extremely cold."And despite being 5,000 times cooler than the center of the Sun, the diamond white dwarf is still thought to be 2,700 degrees Celsius or 4,892 degrees Fahrenheit.