Israeli astrophysicists solved the mystery of an unusual flash of light in the dark sky that was observed since 14 June 2015 and did not fit any usual models.
When astronomers and astrophysicists observe flashes of light in the dark sky, they usually assume it is a supernova (a star that suddenly increases greatly in brightness because of a catastrophic explosion that ejects most of its mass)
However, the flash of light observed on 14 June 2015 did not fit into something researchers have seen before.
Firstly, the intensity of the light was double that of the brightest supernova recorded followed by other anomalies too.
Postdoctoral fellow Giorgos Leloudas and Prof. Avishay Gal-Yam of the Particle Physics and Astrophysics Department of the Weizmann Institute of Science researched the phenomena alongside colleagues at the Institute, Drs. Paul Vreeswijk, Ofer Yaron and Steve Schulze, Joel Johannson, and Ira Bar, and other researchers from around the world all acknowledged that they are witnessing a very rare event.
For such an event to happen two conditions must occur: the star must stray close enough to the black hole to cross its “event horizon” – the point at which it cannot escape the pull of the giant mass – but the light produced in its destruction must somehow escape the black hole’s all-consuming gravity. For these conditions to occur, the galaxy’s central black hole, which is immense, even by black-hole standards, must be rotating at a relativistic speed – close to the speed of light.
Finally, after observing the light over several months, the team concluded that the best explanation for the unusual flash of light was, the destruction of a star caught in the gravitational tides of an exceptionally massive black hole rotating extremely rapidly.
The results of this research were published In Nature Astronomy research journal.
Prof. Avishay Gal Yam’s research is supported by the Benoziyo Endowment Fund for the Advancement of Science; the Yeda-Sela Center for Basic Research; and the Deloro Institute for Advanced Research in Space and Optics. Prof. Gal-Yam is the recipient of the Helen and Martin Kimmel Award for Innovative Investigation.