Astronomers have spotted a red giant star, some 11 times the mass of our own sun, swallowing up a planet. A similar fate awaits Earth, about five billion years from now.
How’s this for a depressing look into Earth’s potential future: astronomers have witnessed the first evidence of a planet’s destruction by its aging star as it expands into a red giant.
“A similar fate may await the inner planets in our solar system, when the Sun becomes a red giant and expands all the way out to Earth’s orbit some five-billion years from now,” said Alex Wolszczan, from Penn State, University, who led a team which found evidence of a missing planet having been devoured by its parent star. Wolszczan also is the discoverer of the first planet ever found outside our solar system.
The planet-eating culprit, a red-giant star named BD+48 740 is older than the Sun and now has a radius about eleven times bigger than our Sun.
The evidence the astronomers found was a massive planet in a surprising highly elliptical orbit around the star – indicating a missing planet — plus the star’s wacky chemical composition.
“Our detailed spectroscopic analysis reveals that this red-giant star, BD+48 740, contains an abnormally high amount of lithium, a rare element created primarily during the Big Bang 14 billion years ago,” said team member Monika Adamow from the Nicolaus Copernicus University in Torun, Poland. “Lithium is easily destroyed in stars, which is why its abnormally high abundance in this older star is so unusual.