Astronomers have discovered a planet that is literally falling apart as it orbits its star. Located about 140 light-years from Earth, BD+05 4868 Ab is a tiny world with low mass, which makes it easy to lose massive amounts of material into space. With every blistering 30-hour orbit, the planet sheds as much mass of molten rock as an entire Mount Everest. This process leaves behind a blazing trail of molten lava, creating a comet-like tail that stretches up to 9 million kilometers long.
The discovery was made using NASA’s Transiting Exoplanet Survey Satellite (TESS) observatory and reveals that the planet is experiencing a runaway process of evaporation due to its close proximity to its star. The team predicts that it will take around 1 to 2 million years for the entire planet to fully disintegrate.
This is not the first time a disintegrating world has been discovered, but BD+05 4868 Ab stands out with its exceptionally long comet-like tail. Only three other disintegrating worlds have been identified among the over 6,000 discovered exoplanets, and this one’s evaporation process is considered the most catastrophic.
The planet’s transit appears every 30.5 hours, making it an ideal target for NASA’s James Webb Space Telescope to study the composition of the vaporized rock trailing behind the planet. The discovery offers a rare opportunity to watch a planet disintegrate in real time and provides valuable insights into the diversity and potential habitability of terrestrial planets outside our solar system.
The team plans to carry out follow-up observations this summer using the JWST, which will directly measure the interior composition of a rocky planet, shedding light on the characteristics that make certain worlds susceptible to disintegration.
Source: https://www.space.com/the-universe/exoplanets/astronomers-discover-doomed-planet-shedding-a-mount-everests-worth-of-material-every-orbit-leaving-behind-a-comet-like-tail