Burping and crash diets – black holes reveal New Year’s resolutions

6 Jan 2016

An illustration of a baby black hole. Image via NASA/CXC/M.Weiss

With the new year upon us, astronomers have discovered two bizarre black holes in different locations with one showing itself to be burping and another to be undergoing a slimming regime.

When it comes to our understanding of black holes, we as a species have yet to fully grasp what exactly is going on within the cosmic bar that the gravity vacuum is so strong that not even light can escape its pull.

However, in the past few days, there have been two rather interesting discoveries made by two separate teams of astronomers that appear to show phenomena we have yet to see them undergo.

The first, discovered by astrophysicist Julie Comerford from the University of Colorado Boulder, has found what is being described as a ‘skinny’ black hole due to the apparent lack of stars that surround it.

With nearly 500-times fewer stars surrounding it compared to another relatively close black hole, its appearance at the edge of the galaxy dubbed SDSS J1126+2944 is that of what is known as an intermediate, or medium-sized, black hole.

Slimming galaxy

The arrow indicates galaxy SDSS J1126+2944, or the ‘slimming’ galaxy. Image via Julie Comerford

This is pretty significant given that, until now, there have been no observable examples of a black hole of this size, with this black hole adjacent to what is being described as a ‘cosmic beauty mark’ of stars.

With the likelihood that Comerford is witnessing the gradual merging of two galaxies, there exists the possibility this medium-sized black hole was once a supermassive black hole that was ripped apart by gravitational forces.

“In other words, Comerford says, “it went on a major crash diet.”

Too much cosmic turkey

Meanwhile, in an altogether different part of the universe, a black hole in galaxy NGC 5194, 26m light years away from Earth, is feeling a little overfed to the point that is now ‘burping’ huge quantities of gas into the universe.

Using NASA’s Chandra space telescope, Eric Schlegel and his team from the University of Texas compiled X-ray images of the black hole showing the hotter gas sweeping the cooler hydrogen gas ahead of it.

It is likely that the black hole emitting this burp, much like many of us did at Christmas, gorged on gas emitted by a neighbouring, larger galaxy with energy levels reaching such heights that the only way for it to go was out.

Burping galaxy

The two waves of ‘burps’ outlined with the black hole in the centre. Image via NASA/CXC/Univ of Texas/E Schlegel et al

Schlegel and the team have been quick to point out this instance as an example whereby our perception of black holes as solely forces of destruction in the universe is misguided, with these burping events potentially leading to the birth of stars.

The two burps are understood to be ancient when compared with the black hole, with the inner burp believed to be approximately 3m-years-old, while the outer burp is twice as old.

“This activity is likely to have had a big effect on the galactic landscape,” Schlegel said.

Colm Gorey was a senior journalist with Silicon Republic