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The best map of dark matter EVER

The largest single high-definition map of mysterious dark matter has been produced.

It is the first in a series of maps of the cosmos that will eventually allow a 3D view of dark matter across one eighth of the night sky.

And the map should allow astronomers to study how galaxies formed in the universe.

University of Manchester researchers have revealed an HD dark matter map (shown). It shows clumps of mystery particles across 0.4 per cent of the sky. The goal is to eventually map 12.5 per cent over five years. Red here shows more dark matter, and blue shows less. The moon is shown top left for scale

A team from the University of Manchester, led by Dr Sarah Bridle, has spent the past two years measuring the shapes of galaxies used to construct the map.

And the map was released today at the April meeting of the American Physical Society in Baltimore, Maryland.

It was created using data captured by the Dark Energy Camera, a 570-megapixel imaging device that is the primary instrument for the Dark Energy Survey (DES) led by Fermilab in the US.

WHAT IS DARK MATTER? 

When physicists study the dynamics of galaxies and the movement of stars, they are confronted with a mystery.

If they only take visible matter into account, their equations simply don't add up; the elements that can be observed are not sufficient to explain the rotation of objects and the existing gravitational forces. There is something missing.

From this they deduced that there must be an invisible kind of matter that does not interact with light but does, as a whole, interact by means of the gravitational force.

Called 'dark matter', this substance appears to make up at least 80 per cent of the matter in the known universe. 

And the project is run overall as part of the five-year Dark Energy Survey (DES), and is the largest map of this detail.

Of course, we can’t actually directly observe dark matter yet - so the survey instead looks for its noticeable effect on galaxies.

Studying this enables the predicted amounts of dark matter in a given area to be mapped, based on its gravitational effects. 

‘Dark matter could equally be called “transparent matter”, because we see things behind it that gets distorted by gravity,’ Dr Bridle told MailOnline.

In the map she explained we’re seeing about 150 times the area of the full moon, which is about 0.4 per cent of the whole sky.

The goal of the DES is to map 12.5 per cent of the entire sky, creating a 3D map of dark matter - and dark energy.

‘It is amazing to see a map of the dark matter over such a large region of the sky, and the full Dark Energy Survey mass map will be more than 30 times bigger still,’ Dr Bridle said in a separate statement.

'Analysis of the clumpiness of the dark matter in the maps will also allow us to probe the nature of the mysterious dark energy, believed to be causing the expansion of the universe to speed up.' 

This mosaic image shows the different telescope shots that were combined to make the dark matter map. The survey has just completed its second year. As scientists expand their search they’ll be able to better test current cosmological theories by comparing the amounts of dark and visible matter

The survey has just completed its second year. As scientists expand their search, they’ll be able to better test current cosmological theories by comparing the amounts of dark and visible matter.

Those theories suggest that, since there is much more dark matter in the universe than visible matter, galaxies will form where there are large concentrations of dark matter (and hence stronger gravity) present.

So far, the DES analysis backs this up. The maps show large filaments of matter along which visible galaxies and galaxy clusters lie and cosmic voids where very few galaxies reside.

Follow-up studies of some of the enormous filaments and voids, and the enormous volume of data, collected throughout the survey will reveal more about this interplay of mass and light.

These maps show how the amount of dark matter corresponds to the formation rate of galaxies. On the left, galaxies can be seen near dark matter clumps (in red), and further away from sparse regions (blue). The image on the right shows some of the regions of sky that were studied

The team at Manchester analysed 130 million separate telescope images of galaxies to make the map.

The process of measuring the galaxies is so complex and time consuming that some of the world's largest supercomputers are needed to do it.

Each time a new catalogue is made it takes about as much computing power as running 500 ordinary desktop computers for two weeks.

'We have to measure the shape of each galaxy - how distorted it is - with extremely high precision, about one part in 1000,' said Dr Joe Zuntz, also of the University of Manchester, who has been making the measurements.

The survey uses the 13ft (four metres) Victor M. Blanco Telescope (middle) located at the Cerro Tololo Inter-American Observatory (CTIO) in Chile, outfitted with a newly designed, state-of-the-art Dark Energy Camera (DECam). It will be completed by 2018, mapping dark matter of an eighth of the sky in the process

Dark matter, the mysterious substance that makes up 85 per cent of all matter in the universe, is invisible to even the most sensitive astronomical instruments because it does not emit or block light.

But its effects can be seen using a technique called gravitational lensing - studying the distortion that occurs when the gravitational pull of dark matter bends light around distant galaxies.

Understanding how the clumpiness of dark matter changes with time will reveal the nature of the enigmatic dark energy, which is the ultimate goal of the survey.

The dark matter map released makes use of early DES observations and covers only about three percent of the area of sky DES will document over its five-year mission.

Read more: http://www.dailymail.co.uk/sciencetech/article-3037244/The-best-map-dark-matter-High-definition-diagram-reveals-clumps-mystery-particles-explain-galaxies-form.html#ixzz3YEXLSgmM 
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