Another Galaxy found by scientists
According to the study, published in the Astrophysical Journal, the researchers expect that the holes at these galaxies that are smaller average about 4,00,000 times as heavy.
For the findings, Reines and her colleagues used the US National Science Foundation’s Karl G. Jansky Very Large Array (VLA) to make the discovery. They used the VLA to discover the massive black hole in a dwarf starburst galaxy in 2011. That discovery was a surprise to astronomers and spurred a radio look for more.
The scientists began by selecting a sample of galaxies in the Atlas, a catalog of galaxies made with visible-light telescopes.
They picked galaxies totalling less than three billion times the mass of the Sun, roughly equal to the Large Magellanic Cloud, a companion of the Milky Way.
From this sample, they chose candidates that also appeared in the National Radio Astronomy Observatory’s Faint Images of the Radio Sky at Twenty centimetres (FIRST) survey, made between 1993 and 2011.
Then they used the VLA to create new and more sensitiveimages of the galaxies that were selected of 111.
“The new VLA observations revealed that 13 of these galaxies have strong evidence for a massive black hole that is actively consuming surrounding material. We were quite surprised to find that, in approximately half of those 13 galaxies, the black hole isn’t in the centre of the galaxy, unlike the situation in larger galaxies,” Reines said.
The scientists said this indicates that the galaxies and others earlier in their history have united.
This is consistent with computer simulations predicting that approximately half of the massive holes in dwarf galaxies will be found wandering in the outskirts of the galaxies.
“This work has taught us that we must broaden our hunts for massive black holes in dwarf galaxies beyond their centres to get a more complete understanding of the population and learn what mechanisms helped form the first massive black holes in the early Universe,” Reines said.