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Astronomers have mapped dark matter on the largest scale ever observed
Good news:
Those tiny distortions in the images of distant galaxies, called cosmic shear.
And here's Dark Matter map and the full moon to scale.
The observations show that dark matter in the Universe is distributed as a network of gigantic dense (light) and empty (dark) regions, where the largest dense regions are about the size of several Earth moons on the sky.
The densest regions of the dark matter host massive clusters of galaxies. To get these accumulated images over five years scientists used the wide field imaging camera MegaCam, a 1 degree by 1 degree field-of-view 340 Megapixel camera on the CFHT in Hawaii.
The scientists are optimistic:
http://www.physorg.com/news/2012-01-astronomers-universe-dark-unprecedented-scale.html
http://www.physorg.com/news/2012-01-clearest-picture-dark-energy.html
The bigger more accurate and better Dark Matter map they get the better we will understand our Universe. It will shed some light on dark energy as well.
I just hope there will be more and more of new tools available to physicists in their study so we could get more info.
Good news:
An international team of researchers lead by Van Waerbeke and Heymans achieved their results by analysing images of about 10 million galaxies in four different regions of the sky. They studied the distortion of the light emitted from these galaxies, which is bent as it passes massive clumps of dark matter during its journey to Earth.
Those tiny distortions in the images of distant galaxies, called cosmic shear.
And here's Dark Matter map and the full moon to scale.
The observations show that dark matter in the Universe is distributed as a network of gigantic dense (light) and empty (dark) regions, where the largest dense regions are about the size of several Earth moons on the sky.
The densest regions of the dark matter host massive clusters of galaxies. To get these accumulated images over five years scientists used the wide field imaging camera MegaCam, a 1 degree by 1 degree field-of-view 340 Megapixel camera on the CFHT in Hawaii.
Galaxies included in the survey are typically six billion light years away. The light captured by the telescope images used in the study was emitted when the Universe was six billion years old – roughly half the age it is today.
The scientists are optimistic:
Professor Ludovic Van Waerbeke, from the University of British Columbia, said: "It is fascinating to be able to 'see' the dark matter using space-time distortion. It gives us privileged access to this mysterious mass in the Universe which cannot be observed otherwise. Knowing how dark matter is distributed is the very first step towards understanding its nature and how it fits within our current knowledge of physics."
Dr Catherine Heymans, a Lecturer in the University of Edinburgh's School of Physics and Astronomy, said: "By analysing light from the distant Universe, we can learn about what it has travelled through on its journey to reach us. We hope that by mapping more dark matter than has been studied before, we are a step closer to understanding this material and its relationship with the galaxies in our Universe."
Professor Lance Miller, from Oxford University said: "This result has been achieved through advances in our analysis techniques which we are now applying to data from the Very Large Telescope's (VLT) Survey Telescope in Chile."
Professor Koen Kuijken, from Leiden University, said: "Over the next three years we will image more than 10 times the area mapped by CFHTLenS, bringing us ever closer to our goal of understanding the mysterious dark side of the Universe."
http://www.physorg.com/news/2012-01-astronomers-universe-dark-unprecedented-scale.html
http://www.physorg.com/news/2012-01-clearest-picture-dark-energy.html
The bigger more accurate and better Dark Matter map they get the better we will understand our Universe. It will shed some light on dark energy as well.
Gravity tends to pull matter together into dense concentrations, but dark energy acts as a repulsive force that slows down the collapse. Thus the clumpiness of the dark matter maps provides a measurement of the amount of dark energy in the universe.
I just hope there will be more and more of new tools available to physicists in their study so we could get more info.
Teams from Fermilab and Berkeley Lab used galaxies from wide-ranging SDSS Stripe 82, a tiny detail of which is shown here, to plot new maps of dark matter based on the largest direct measurements of cosmic shear to date.