"Fake Diamond" Star Discovered

Dubbed LS IV-14 116, the faint, blue star lies about 2,000 light-years from the sun. Detailed new measurements reveal the star to be the most zirconium-rich known to date, with levels more than 10,000 times higher than those in our sun.

While real diamonds are made of carbon, jewellers make false diamonds out of zirconium dioxide crystals, aka cubic zirconia. The mineral zirconium silicate, or zircon, is also widely used as a gemstone. (Related: "'Diamond Planets' Hint at Dazzling Promise of Other Worlds.")

In addition to zirconium, astronomers studying LS IV-14 116 found chemical signatures for high amounts of three other elements rarely seen in stellar atmospheres: strontium, germanium, and yttrium.

"It really is quite an oddball," said team member Simon Jeffery of Armagh Observatory in Northern Ireland.

An In-Between Star

Jeffery and colleagues found the high amount of zirconium while studying the chemistry of LS IV-14 116. Previous measurements had indicated the star is a rare, helium-rich hot subdwarf.

When less massive stars die, they swell up and start shedding their outer layers of gas, becoming red giants. When all the gas is released, the leftover core of the dead star is called a white dwarf.

Hot subdwarfs represent a phase of evolution for some stars that comes between red giants and white dwarfs, so studying them will give scientists greater insight into how stars live and die. (Related: "Red Giant Sun May Not Destroy Earth.")

Using the Anglo-Australian Telescope at Siding Spring Observatory in New South Wales, the team took a closer look at LS IV-14 116's spectral lines, the frequencies of light emitted by the star, as determined by the elements and molecules present.

The spectral line for zirconium was not only strong, it corresponded to a form of the metal that exists only at temperatures above 20,000 degrees Celsius. This form had previously never been seen in any astronomical object


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