A supermassive black hole swallows a star, blasting its remains to Earth
A supermassive black hole swallowed a star, tore it apart and uniquely ejected a beam of light from its center.
IN research report published Wednesday, astronomers say a previously unknown black hole became known to observers when a star passed too close and was swallowed up.
Astronomers then observed a jet of “afterglow” from the crash, which experts call a Tidal Disruption Event (TDE), heading straight for to Earth.
“The event began when an ill-fated star approached the supermassive black hole (SMBH) on a nearly parabolic trajectory and was torn apart in a stream of gaseous debris,” says the science paper published on November 30. “About half of the mass remained bound to the black hole, underwent general relativistic apsidal precession as the gas fell back to the pericenter, and then produced strong shocks at the self-crossing point.”
Scientists said the beam fired – AT2022cmc or “infrared/optical/ultraviolet light curve” – was initially red in color before decaying over four days and changing to a blue hue.
The astronomers added: “Optical and ultraviolet observations revealed a rapidly decaying red ‘flare’ that rapidly transitioned to a slow blue ‘plateau’, allowing the study of two components generated by the tidal disruption: the relativistic jet and the thermal component of bound stellar debris accreting onto the black hole.”
The exploded debris was so intensely bright that astronomers detected a TDE from dwarf galaxy a million light years away.
The paper adds: “Observations of a bright double at other wavelengths, including X-ray, submillimeter and radio, support the interpretation of AT2022cmc as a synchrotron-containing TDE jet.”
TDE was discovered in February 2022, before the journal Science News received the article about it in April 2022, and the study was finally accepted in October 2022.
TDEs have been observed before, such as AT 2020neh in June 2020.
Ryan J. Foley, a co-author and UC Santa Cruz astronomer, said this initial discovery will help astronomers find other TDEs and new dwarf galaxies.
“This discovery created widespread excitement because we can use tidal perturbation events not only to find more intermediate mass black holes in quiescent dwarf galaxies, but also to measure their masses,” Foley said in a Science paper co-published on 10 November.
The discovery followed years of research, as the distant galaxy was first observed in June 2020 and confirmed with data from the Young Supernova Experiment. It was observed again from July 1, 2020 to July 17, 2020; then from August 5, 2020 to September 6, 2020.
“During 24 months of YSE operations, we observed only one AT 2020neh-like event, observing flights for approximately 6 months each. This equates to one event per year within the YSE observing volume,” the scientific paper says.
These unique findings could lead to even more discoveries in distant galaxies that would otherwise be undetectable without visible light from the explosion.