How monster black hole ate star and spewed it out
A “monster” black hole gradually eating a helpless star millions of light years from Earth has been tracked by scientists.
The almost decade-long study by a team of international astronomers have captured jets of stellar material spewed from the black hole as it consumed the trapped star for the first time.
The results have been published in the journal Science and could help scientists better understand the formation of galaxies in the early universe.
Astronomers’ interest began in January 2005 when they detected brilliant infrared light from a pair of merging galaxies 150 million light-years from Earth – Arp 299. Further observations recorded bright radio waves from the region.
The signs pointed to a supernova – when a star increases in brightness before a catastrophic explosion – but observations by NASA’s Spitzer Space Telescope showed the source was far too bright to be one.
And the astronomers were also intrigued by radio waves – formed by debris from the trapped star - travelling at nearly light-speed from Arp 299.
This suggested it was a Tidal Disruption Event (TDE) – a star being torn apart by a supermassive black hole.
Years of further observations, data analysis and modelling confirmed this.
“The infrared and radio emissions came from the disruption of a hapless star being devoured by the supermassive black hole when it passed too close to this cosmic monster,” said lead astronomer Seppo Mattila of the University of Turku in Finland.
TDEs are extremely rare events and require a painstaking search of many galaxies to find one.
But now astronomers hope improved radio and infrared observatories may lead to more being found.
“The event we have discovered could thus be just the tip of the iceberg of a hidden population of TDEs that were more common when the universe was much younger than today,” Mattila says.