Diamond Star.

A while ago, astronomers have discovered a star made of 10 billion trillion trillion carats of diamond!

The huge cosmic diamond – technically known as BPM 37093 – is actually a crystallised white dwarf. A white dwarf is the hot core of a star, left over after the star uses up its nuclear fuel and dies. It is made mostly of carbon.

For more than four decades, astronomers have thought that the interiors of white dwarfs crystallised, but obtaining direct evidence became possible only recently.

The white dwarf is not only radiant but also rings like a gigantic gong, undergoing constant pulsations.

"By measuring those pulsations, we were able to study the hidden interior of the white dwarf, just like seismograph measurements of earthquakes allow geologists to study the interior of the Earth.

"We figured out that the carbon interior of this white dwarf has solidified to form the galaxy’s largest diamond," says Metcalfe.

Link – via reddit