Proto supermassive binary black hole detected in X-rays

April 6, 2006

An international team of astronomers led by D. Hudson from the University of Bonn has detected a proto supermassive binary black hole in images of NASA's Chandra X-ray observatory. They found that these two black holes are gravitationally bound and orbit each other. Their results will be published in an upcoming issue of Astronomy & Astrophysics.

An international team of astrophysicists, led by D. Hudson from the University of Bonn and including the U.S. Naval Research Laboratory and the University of Virginia, presents their X-ray detection of a proto supermassive binary black hole. Their results will be published in an upcoming issue of Astronomy & Astrophysics. The image of this proto binary black hole was obtained with NASA's Chandra X-ray Observatory. The two black holes have already been seen in radio images. The new X-ray images provide unique evidence that these two black holes are in the process of forming a binary system; that is, they are gravitationally bound and orbit each other.

This image shows the central region of the galaxy cluster Abell 400. The colour coding gives the temperature of the X-ray emitting gas trapped in the cluster: black-cold (18 million degrees Celsius) to white-hot (38 million degrees Celsius). The contours show the radio emission from the jets of plasma being expelled by the black holes. As the two black holes stream through the gas at supersonic velocities, the jets are bent toward the top of the image. The gas in front of the black holes is compressed and heated, as seen by the hotspot below them. The inset shows a blow up of the central regions. Each dot represents a position where an X-ray photon has struck Chandra´s X-ray camera. The two black holes are seen as bright regions where as many as 250 X-ray photons struck the camera. The contours again show the radio emission from the black holes and the jets of plasma being ejected from them.

The two black holes are located in the nearby galaxy cluster Abell 400. With high-resolution Chandra data, the team was able to spatially resolve the two supermassive black holes (separated by 15") at the centre of the cluster. Each black hole is located at the centre of its respective host galaxy and the host galaxies appear to be merging. It is not, however, just the two host galaxies that are colliding - the whole cluster in which they live is merging into another neighbouring galaxy cluster.

Using these new data, the team show that the two black holes are moving through the intracluster medium at the supersonic speed of about 1200 km/s. The wind from such a motion would cause the radio plasma emitted from these two black holes to bend backwards. Although this bending had been observed previously, the cause of it was still being debated. Since the bending of the jets due to this motion is in the same direction, it suggests that the two black holes are travelling along the same path within the cluster and are therefore gravitationally bound.

These two black holes became gravitationally bound when their host galaxies collided. In several million years, the two black holes will probably coalesce causing a burst of gravitational waves, as predicted by Einstein's theory of relativity. This event will produce one of the brightest sources of gravitational radiation in the Universe. Although we will not be around to see this particular one, the observations provide additional evidence that such bound systems exist and are currently merging. The gravitational waves produced by these mergers are believed to be the biggest source of gravitational waves to be detected by the future Laser Interferometer Space Antenna (LISA).

Source: Journal Astronomy and Astrophysics

Explore further: Dense star clusters shown to be binary black hole factories

Related Stories

Dense star clusters shown to be binary black hole factories

July 29, 2015

The coalescence of two black holes—a very violent and exotic event—is one of the most sought-after observations of modern astronomy. But, as these mergers emit no light of any kind, finding such elusive events has been ...

Why can't we see the center of the Milky Way?

July 10, 2015

For millennia, human beings have stared up at the night sky and stood in awe of the Milky Way. Today, stargazers and amateur astronomers continue in this tradition, knowing that what they are witnessing is in fact a collection ...

Chandra finds evidence for serial black hole eruptions

June 10, 2015

Astronomers have used NASA's Chandra X-ray Observatory to show that multiple eruptions from a supermassive black hole over 50 million years have rearranged the cosmic landscape at the center of a group of galaxies.

Cosmic ray observatory to expand

June 15, 2015

Physicists plan a $6.4 million expansion of the $25 million Telescope Array observatory in Utah so they can zero in on a "hotspot" that seems to be a source of the most powerful particles in the universe: ultrahigh-energy ...

Recommended for you

Innovations from the wild world of optics and photonics

August 2, 2015

Traditional computers manipulate electrons to turn our keystrokes and Google searches into meaningful actions. But as components of the computer processor shrink to only a few atoms across, those same electrons become unpredictable ...

Shedding light on millipede evolution

August 2, 2015

As an National Science Foundation (NSF)-funded entomologist, Virginia Tech's Paul Marek has to spend much of his time in the field, hunting for rare and scientifically significant species. He's provided NSF with an inside ...

Better together: graphene-nanotube hybrid switches

August 2, 2015

Graphene has been called a wonder material, capable of performing great and unusual material acrobatics. Boron nitride nanotubes are no slackers in the materials realm either, and can be engineered for physical and biological ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.