A whole new world just rose from the ashes of a dead star

Astronomers have found the first-ever planet that may have been born from the remains of a star that already died. The host is a white dwarf — the small, dense core left behind after a sunlike star burns through its fuel and collapses — called HS 0209+0832, about 270 light-years away. A team at the University of Warwick in England studied it with NASA's Hubble Space Telescope and other instruments, and found unusual traces of heavy elements — especially the rare element niobium, seen in a white dwarf for the first time — raining down onto the dead star. That's the chemical fingerprint of a brand-new planet condensing out of the debris the star threw off as it died. Then came the clincher: NASA's TESS satellite caught a faint brightness signal repeating every 4.4 days, matching a giant planet circling the stellar remnant. Planets had been seen surviving their star's death before, but never one built from scratch out of the ashes afterward. The study was published Monday in the journal Nature Astronomy.