Mysterious phenomena in a gigantic galaxy-cluster collision

Mysterious phenomena in a gigantic galaxy-cluster collision
Abell 2256, in a "true color" radio image made with the VLA. Credit: Owen et al., NRAO/AUI/NSF

Researchers using the Karl G. Jansky Very Large Array (VLA) have produced the most detailed image yet of a fascinating region where clusters of hundreds of galaxies are colliding, creating a rich variety of mysterious phenomena visible only to radio telescopes.

The scientists took advantage of new VLA capabilities to make a "true color" radio image. This image shows the region as it would appear if human eyes were sensitive to radio waves instead of . In this image, red shows where longer radio waves predominate, and blue shows where shorter predominate, following the pattern we see in visible light.

The image shows a number of strange features the astronomers think are related to an ongoing collision of . The region is called Abell 2256, and is about 800 million light-years from Earth and some 4 million light-years across. The image covers an area in the sky almost as large as the full moon. Studied by astronomers for more than half a century with telescopes ranging from radio to X-ray, Abell 2256 contains a fascinating variety of objects, many of whose exact origins remain unclear.

With monikers such as "Large Relic," "Halo," and "Long Tail," the features in this region are seen in greater fidelity than ever before, said Frazer Owen, of the National Radio Astronomy Observatory (NRAO). "The image reveals details of the interactions between the two merging clusters and suggests that previously unexpected physical processes are at work in such encounters," he said.

The researchers presented their results in the Astrophysical Journal.


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Journal information: Astrophysical Journal

Citation: Mysterious phenomena in a gigantic galaxy-cluster collision (2015, March 10) retrieved 27 May 2019 from https://phys.org/news/2015-03-mysterious-phenomena-gigantic-galaxy-cluster-collision.html
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Mar 10, 2015
That is some strange stuff. What could leave a trail of radio waves like the line in the middle? Has anything like that been seen by a radio telescope before?

yyz
Mar 10, 2015
@Moebius

"What could leave a trail of radio waves like the line in the middle? Has anything like that been seen by a radio telescope before?"

That's a head-tail or (narrow-angle tailed) radio galaxy, representing a galaxy with a long, narrow one sided radio jet. The feature is even named 'The Long Tail' and extends over 540 kpc from a 15th magnitude(optical) galaxy in the cluster. There are other known, though less extreme, examples of this type of radio galaxy (one being visible to the right of The Long Tail in the picture above).

Further details about these VLA observations and images of this cluster (esp. Fig 13) may be found in this paper: http://arxiv.org/abs/1408.5931

Mar 10, 2015
Further details about these VLA observations and images of this cluster (esp. Fig 13) may be found in this paper: http://arxiv.org/abs/1408.5931
@yyz
thanks for that link!

Mar 10, 2015
If it's a jet why isn't it spreading out at the end like every other jet I've seen? Looks more like a laser beam. Is it also normal for the frequency to change from one end to the other?

Mar 10, 2015
What could leave a trail of radio waves like the line in the middle?
IMO it's a pair of jet from ultramassive black hole, produced with merger. You can clearly see the Doppler effect there..
Looks more like a laser beam
Many galactic jets are actually quite narrow.

Mar 11, 2015
If one watches the 6 part series called "The Primer Fields' this would be readily understandable. The work plasma physicists are doing with magnetic fields and electric current are providing solid data that corresponds nicely with recent radio telescope images.
This and other radio telescope data is providing further support for theories of galaxy and star formation put forth by the electric universe paradigm.
It should be soon that radio astronomers and astrophysicists notice these "other forces" are electrical (electromagnetic) in nature and explain many of the problems that confound them.

Mar 11, 2015
4 million light years across,means that the colored jet shown in the middle must be about 2 million light years long?

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