astroengine writes "It was once the core of a star, but now has the mass of a planet. It is composed of dense carbon with a crystal-like structure. Yes, it's a bona fide planet made from diamond.
The object, called J1719-1438, circles a pulsing companion star (pulsar) about 4,000 light years from Earth in the constellation Serpens (The Snake), which lies about one-eighth of the way toward the center of the Milky Way."
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