Space

Unknown galaxies discovered lurking behind the Milky Way

Hundreds of new galaxies previously hidden from view on the other side of the Milky Way have recently been discovered
Hundreds of new galaxies previously hidden from view on the other side of the Milky Way have recently been discovered
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Hundreds of new galaxies previously hidden from view on the other side of the Milky Way have recently been discovered
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Hundreds of new galaxies previously hidden from view on the other side of the Milky Way have recently been discovered
An artist’s impression of the galaxies found in the "Zone of Avoidance" behind the Milky Way
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An artist’s impression of the galaxies found in the "Zone of Avoidance" behind the Milky Way
The Milky Way as observed from the International Space station
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The Milky Way as observed from the International Space station

In recent radio telescope studies, many hundreds of previously undiscovered galaxies have been found to exist in an area in which an enormous magnetic abnormality known as the "Great Attractor" is located. The new research may help shed light on why our galaxy, along with hundreds of thousands of others, is being inextricably pulled in that direction.

Using an advanced multibeam receiver on the CSIRO Parkes radio telescope in Australia (the instrument recently used as part of the search for extraterrestrial intelligence), researchers from Australia, South Africa, the US and the Netherlands were able to penetrate the stars and dust of the Milky Way that blocked the direct view of the other side of the galaxy, and peer into a region of which very little is known. In so doing, the team identified some 883 galaxies, where around one third had never been previously identified.

"The Milky Way is very beautiful of course and it's very interesting to study our own galaxy, but it completely blocks out the view of the more distant galaxies behind it," said Professor Lister Staveley-Smith, from The University of Western Australia node of the International Centre for Radio Astronomy Research (ICRAR).

The discovery may help to explain the Great Attractor region, which appears to be drawing the Milky Way and other galaxies towards it with a gravitational force equivalent to a million billion Suns. Sited at a relatively close distance to Earth in astronomical terms, and known as "The Zone of Avoidance" due to its hidden nature, the area is around 250 million light years away. According to Professor Staveley-Smith, the Great Attractor has been a constant source of speculation and research from the time when extreme aberrations in expected universal expansion were discovered in the area almost 50 years ago.

An artist’s impression of the galaxies found in the "Zone of Avoidance" behind the Milky Way
An artist’s impression of the galaxies found in the "Zone of Avoidance" behind the Milky Way

"We don't actually understand what's causing this gravitational acceleration on the Milky Way or where it's coming from," he said. "We know that in this region there are a few very large collections of galaxies we call clusters or superclusters, and our whole Milky Way is moving towards them at more than two million kilometres per hour."

Another astronomer participating in the study, Prof. Renée Kraan-Korteweg of the University of Cape Town concurred that researchers have been attempting to chart the galaxies suspected of being obscured behind the Milky Way for many years now.

"We've used a range of techniques but only radio observations have really succeeded in allowing us to see through the thickest foreground layer of dust and stars," said Professor Kraan-Korteweg. "An average galaxy contains 100 billion stars, so finding hundreds of new galaxies hidden behind the Milky Way points to a lot of mass we didn't know about until now."

The Milky Way as observed from the International Space station
The Milky Way as observed from the International Space station

The Great Attractor – also known as theNorma Cluster – has a mass equivalent to that of thousands of galaxies and, whilst it ishuge, its size still doesn't fully account for the enormous pull beingmeasured. It seems that the Great Attractor and galaxies surrounding it(including our own) are hurtling toward something even bigger. Dubbed theShapley Supercluster, this conglomeration of more than 8,000 galaxies has anincredible mass of more than ten million billion of our suns, and every galaxyin our region of the Universe is heading toward it.

Of the many newly-identified structures revealed by the research, three new galaxy concentrations (NW1, NW2, and NW3) and two new clusters (CW1 and CW2, one of which forms part of the striking 180° long filament that dominates the southern sky), may be key in helping explain the movement of the Milky Way and other galaxies towards the Great Attractor region.

Much of this research has been made possible with the use of new technology being fitted to radio astronomical devices such as the Parkes Radio Telescope that, according to researchers, is enabling much faster surveying and recording of large swathes of the heavens. As a result, more details of areas such as that of the Zone of Avoidance may be more quickly gleaned, and further light shed on the reasons so many galaxies are being attracted to it.

"With the 21-cm multibeam receiver on Parkes we're able to map the sky 13 times faster than we could before and make new discoveries at a much greater rate," said Dr. Bärbel Koribalski of CSIRO Astronomy and Space Science.

The findings were recently published in the Astronomical Journal.

Source: International Centre for Radio Astronomy Research

5 comments
GregSmith5a5d6b514f8a4f66
Great article. This is amazing news which possibly adds one more nail in the coffin of the Big Bang Theory. That idea never seemed to make sense to me for various reasons. The Zone of Avoidance and the Shapely Supercluster offer intriguing ideas that will take us far beyond our current theories! We are still at the very beginning of understanding the universe.
artmez
The article states the Milky Way is accelerating in this direction, but it only states a velocity of two million kilometres per hour. So what is (the estimate of) the acceleration? In the last 50 years, we have only shifted about 0.25 seconds of arc (assuming our sun takes 250 million year to rotate about our galaxy), so that alone should have exposed more space (not to mention the great strides we have done in space observation).
Douglas Bennett Rogers
Will the eventual collapse produce a new Big Bang?
Don Duncan
Isn't the expression "unknown galaxies discovered" redundant? Know galaxies can't be discovered, so all discoveries must logically be of unknown origin. Is the 'verse expanding or not? Isn't the expansion rate increasing? Doesn't that mean every galaxy is moving away from each other? Or every galaxy cluster is moving apart? So how can our galaxy and all those in our part of the 'verse (100s of thousands of galaxies) be moving toward the Zone of Avoidance? Doesn't that contradict the expanding 'verse model? And why is there three names for this phenomena, Z. o. A., The Great Attractor, and The Norma Cluster? How much bigger is the Shapley Supercluster? How is the speed of convergence calculated? Doesn't that require a common point of reference? What point? Where? How is the point chosen? What is the difference between a galaxy concentration, cluster, and supercluster? Could these recent discoveries of so much mass mean we don't need the "dark energy" theory because we can suppose all the missing mass will be discovered?
2_OK
Well, it looks like it is start of the big change, with the respect of the things we have heard yesterday. However, might be potential for a dark matter, you know some of the galaxies are not visible because they are hiding and that might add up some missing things. However if we look at the things from some other perspective it is like when you compare planets of the sun as a system and you compare that with the galaxy they spin differently because they might be way different, and not even comparable after all. Now, about those waves. For God sake, why they don't make formula for force like> quntum_influence * weight + Newton_influence * weight + Einstain_influence * weight And then make one formula from those ones that are not connected and you solve problem once for all the time about that, it is way more compact like that. However those parts are from Ainstein good years, when his wife was some Milena Maric... I just don't understand why no body talks about her, she is a woman and ... one more thing that is obvious and I just don't get it... That might also be reason why Albert had no success after he had found some other girls more interesting. There are so many things ...