An empty place in space, where gravity pull is so much that even light itself can not escape is known as a black hole. Black holes can be big or small and to determine their size scientists at the University of Illinois conducted a study and found that consumption of matter in the accretion disk around it is directly related to its mass.
A recent study published in the journal Science has found out that supermassive black holes while feeding emits a noticeable flickering light, whose pattern is directly related to their mass.
Black holes with masses of millions or billions of times that of the sun are known as supermassive black holes and are also the most massive objects in the universe. They are usually found in the center of the galaxies and emit very little light, consequently, scientists have to find them based on their gravitational influence on stars that are near them.
It is believed that in earlier times, supermassive black holes were rapidly growing by consuming material at high rates, thereby emitting massive amounts of radiation which made them glow brighter than the entire galaxy around them.
Colin Burke, an astronomy graduate student and lead author of the recent study, said
“There have been many studies that explored possible relations of the observed flickering and the mass of the SMBH, but the results have been inconclusive and sometimes controversial.”
When they are not much active, supermassive black holes are usually quite dull and don’t emit much light, however, when active and feeding, they produce a pattern of flickering light that can be detected from across the universe, ranging from hours to decades.
After compiling a large set of data of the active, feeding supermassive black holes, it was found out that a shorter duration of flickering indicates a smaller black hole, whereas a longer duration of flickering indicates more massive black holes.
The flickering is described as an equivalent of a burp, by the researchers. It’s these burps that could help us understand the relative sizes of not only supermassive black holes but also the white dwarfs and possibly intermediate-mass black holes or IMBHs, which happen to be much rare and hard to find.
Burke said.
“Now that there is a correlation between the flickering pattern and the mass of the central accreting object, we can use it to predict what the flickering signal from an IMBH might look like.”