Astronomers Watch A Young Star Eat Its Own Planet

Astronomers have long theorized that newly formed stars can occasionally consume their planets, but until now, they have never observed such a feeding frenzy. This artist’s concept illustrates the destruction of a young planet around a star, which can knock material directly into the star itself.(Credit: NASA/CXC/M. Weiss) Astronomers generally agree that planets form out of the massive disks of leftover debris that surround most newborn stars. As these disks of gas and dust orbit their stars, small clumps of material coalesce, ultimately growing larger and larger until they eventually reach planetary status. However, not all planets make it that far. Sometimes, two nascent planets catastrophically collide — and stars apparently do not mourn their dead. In a study published July 18 in The Astronomical Journal, a team of researchers announced they may have, for the first time ever, witnessed a star feeding on the leftover remains of one such planetary collision. These novel observations not only show that a star can devour its own planets, but also bring astronomers one step closer to fully understanding how planets form — or in this case, are destroyed. “Computer simulations have long predicted that planets can fall into a young star, but we have never before observed that,” said lead author Hans Moritz Günther, a researcher at MIT’s Kavli Institute for Astrophysics and Space Research, in a press release. “If our interpretation of the data is correct, this would be the first time that we directly observe a young star devouring a planet or planets.”