A Rare Type of Black Hole Has Been Observed “In Action” Killing a Star.
Medium-mass black holes are the rarest type of black holes. They are significantly heavier than a star but not as massive as the supermassive black holes found at the centers of galaxies. These black holes have only been identified a handful of times.
Now, a medium-mass black hole has been discovered thanks to its terrifying actions: tearing apart a star in a distant dwarf galaxy that was wandering too close, in an event astronomers refer to as a tidal disruption event (TDE), according to Space.com.
Image of a black hole destroying a star – (Photo: ESO).
TDEs become visible as they emit a powerful burst of radiation, so intense that it outshines all the stars in its dwarf galaxy combined. This TDE could help scientists gain a better understanding of the relationship between galaxies and the black holes within them.
The research team has reason to believe that this event – designated AT 2020neh – is the destruction of a star by a black hole.
Modeling the event, they estimate that this black hole has a mass ranging from 50,000 to 800,000 times that of the Sun. For comparison, black holes detected through gravitational waves typically have masses several times that of the Sun. Supermassive black holes at the centers of galaxies can be millions or even billions of times the mass of the Sun.
The lead author who discovered the event, Charlotte Angus from the Niels Bohr Institute (Denmark), stated: “The fact that we captured this medium black hole while it was consuming a star is remarkable.”
Moreover, the researcher can utilize the properties of the flare itself to gain further insights into this elusive population of medium-mass black holes. They may constitute a significant portion of the black holes at the centers of galaxies.
According to IFLScience, supermassive black holes existed very early in the universe – too early for them to fit into many current theories.
One possibility is that the formation of supermassive black holes results from the merger of multiple medium-mass black holes.
Co-author Vivienne Baldassare, a professor of physics and astronomy at Washington State University (USA), remarked: “One of the biggest open questions in astronomy today is how supermassive black holes form.”
Professor Enrico Ramirez-Ruiz, an astronomer and astrophysicist at the University of California, explained: “If we can understand the population of medium-mass black holes – how many there are and where they are located – it could help us determine whether the theory of supermassive black hole formation is correct.”