White Dwarf ‘Diamond’ as Big as the Earth Found
Can you imagine how colossally you’d have to screw up in a relationship to need to buy your way out of it with an earth-sized diamond? Maybe Tiger Woods could do it.
The ‘diamond’ is actually what might be the coldest, faintest white dwarf star ever discovered. It’s so cool that its carbon has crystalized, making it in effect a big diamond.
David Kaplan, a professor at the University of Wisconsin-Milwaukee, and colleagues found the white dwarf using the National Radio Astronomy Observatory’s (NRAO) Green Bank Telescope (GBT) and Very Long Baseline Array (VLBA). If that sounds like a lot of telescopes, keep in mind that because it gives off so little energy the object was very difficult to find.
Kaplan speculates that there should be many more of these cool white dwarfs, but they just aren’t being detected because they are so dim.
White dwarfs represent the end stage of a star, when the material that’s left within them, mostly carbon and oxygen, collapses to a super-dense state. The faint white dwarf is speculated to be 11 billion years old, as old as the Milky Way Galaxy itself.
The researchers found the white dwarf by observing irregularities in its companion star, a pulsar called PSR J2222-0137. A pulsar is a post-supernova neutron star that rapidly spins and sends out a lighthouse like beam of radio waves. The white dwarf warps space around it, causing a delay in the radio waves that helped astronomers eventually pinpoint its location.
However, astronomers have failed to see it with telescopes, perhaps because it is too cold.
[Source: National Radio Astronomy Observatory]
Image: Artist’s conception of the star by B. Saxton, from National Radio Astronomy Observatory