A star located around 650 million light years away in the direction of the constellation Ursa Major defied what has been previously known about the eating habits of black holes by escaping from one. Black holes have been thought to swallow stars whole but the star evaded full absorption, getting away with just a part of its mass torn off.
Astronomers at the Ohio State University observed the event through the All-Sky Automated Survey for Supernovae (ASAS-SN), a project that searches the sky for bursts of light that signal stellar explosions.
At first they thought they were seeing light from an exploding star but later on realized they were instead observing a light flare that came as a result of the black hole eating a portion of the star.
Their observation was published in the Monthly Notices of the Royal Astronomical Society, specifying the event occurred in a galaxy outside of the Laniakea Supercluster.
Thomas Holoien, a doctoral student, led the observation and analysis of the event when it was first detected on Jan. 25, appearing close to the rear left "foot" of the Ursa Major between the Praecipua and Alula Borealis stars.
Because the event was thought to be a supernova at first, it was labeled as ASASSN-14ae. However, the brightness pattern observed was deemed indicative of something else, prompting the astronomers to identify it as a TDE or tidal disruption event.
To further observe the TDE, Holoien and colleagues used telescopes from the McDonald Observatory and the Apache Point Observatory, as well as the Liverpool Telescope and the Large Binocular Telescope. Other data were added from the Swift UltraViolet and Optical Telescope and the Sloan Digital Sky Survey.
Considering the amount of energy that was released by the TDE, they were able to calculate that only a small chunk of the star was swallowed by the black hole. The chunk was about the size of Jupiter or one thousandth of the size of the Sun.
While black holes are believed to consume stars whole, they don't actually do this often. In fact, astronomers put it at just once every 10,000 to 100,000 years. But just how often black holes "snack" on pieces of stars? No word on that yet.
The study primarily received funding support from the CCAPP and the National Science Foundation. Holoien also received funding from the Department of Energy Computational Science Graduate Fellowship. He is the first from the Ohio State University to receive the fellowship, a four-year program that supports students working on big data and high-performance computing science as well as engineering projects.