Assignment #48
December 13th, 2016
Back in 2015 when astronomers discovered an intense flare in a distant galaxy, they considered it the brightest supernova ever observed.
Now, UC Santa Barbara astrophysicists and a group of international colleagues offer an entirely different interpretation based on new astronomical observation data from the Las Cumbres Observatory (LCO), a global robotic telescope network, and the Hubble Space Telescope.
The new information indicates that the event, called ASASSN-15lh, is actually a tidal disruption event (TDE) -- the destruction of a star by a supermassive black hole.
Using images from the Hubble Space Telescope that were not available when ASASSN-15lh was discovered, the scientists found that the event occurred at the center of the galaxy where the supermassive black hole resides. The black hole inferred to lie in this galaxy is more than 100 million times the mass of the sun.
For a star to be tidally disrupted by such a massive black hole -- rather than swallowed whole -- the black hole must be spinning very rapidly.