Astronomers Identify First ‘Second-Generation’ Planet Formed from a Dying Star
Researchers have detected a Jupiter-sized world orbiting the white dwarf HS 0209+0832 that appears to be made from material shed by the star as it died, marking the first known “second-generation” planet of this type.
Astronomers studying the white dwarf HS 0209+0832 reported a distinctive chemical fingerprint rich in niobium, a element produced as stars die. Led by Jamie Williams of the University of Warwick, the researchers interpret the signature as material stripped from a massive planet that formed from the star’s own remnants after it became a white dwarf. Supporting evidence comes from NASA’s TESS mission, which detected a faint, repeating signal every 4.4 days that matches a Jupiter-sized planet in a tight orbit.
The planet’s close proximity causes its atmosphere to boil away, with the escaping gas raining onto the white dwarf and generating the observed elemental excess. If confirmed, this would be the first confirmed second-generation planet, offering a new way to locate similar objects by searching for comparable chemical markers around other dead stars. The finding also expands the prospects for studying habitability around white dwarfs, which are relatively easy to observe. The results were published in Nature Astronomy.
Why it matters
It reveals a new class of planet formed from a star’s death, opening a novel method to find and study such worlds.
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