Oct. 5 (UPI) — Scientists said in a study published Monday that they have found an apparent first: a planet that seems to have formed from the ashes of its dead star.
The authors of the study, published in the journal Nature Astronomy, said the planet is likely a gas giant orbiting a white dwarf about 270 light-years from Earth.
A study of chemical evidence showed that the new planet may have come together from the material created when a sunlike star, dying, turned into first a red giant and then collapsed into a white dwarf.
They said that many white dwarfs accrete, or gradually build up, the debris from “disrupted planetary bodies,” but that this one is accreting “material that is unlike any solar system object” and is “chemically distinct” from the first-generation planets formed when the original star did.
This could make it the first recorded “second-generation” planet, one made from “the stellar material ejected during the giant phase,” the study said.
There are “unusual” traces of some heavy elements on the white dwarf’s surface that suggest it might have created a new planet, the scientists said.
“This planetary material is very rich in an element called niobium,” Jamie Williams, lead study author and a doctoral student in the department of physics at the University of Warwick in England, said to CNN. “It’s the first time that this element is found in a white dwarf, and this implies that the planetary material is made from the ashes of the star as it died.”
The researchers analyzed observations from NASA’s Hubble Space Telescope and other instruments to find this evidence. Analysis of observations from NASA’s Transiting Exoplanet Survey Satellite also showed that the planet could be orbiting a white dwarf.
“What’s interesting about planets orbiting close to white dwarfs is that because white dwarfs cool over time, their habitable zone is very stable,” Williams said. “A second-generation planet could form and then be in the habitable zone for tens of billions of years.”