Proven: Black Holes and Gravitational Waves!

This is fantastic news. Just think: if we could come to an understanding of dark matter, there's no telling what we could accomplish and create.

Gravitational waves from black holes detected
By Pallab Ghosh
Science correspondent, BBC News

Scientists are claiming a stunning discovery in their quest to fully understand gravity.

They have observed the warping of space-time generated by the collision of two black holes more than a billion light-years from Earth.

The international team says the first detection of these gravitational waves will usher in a new era for astronomy.

It is the culmination of decades of searching and could ultimately offer a window on the Big Bang.

Being able to detect gravitational waves enables astronomers finally to probe what they call "dark Universe" - the majority part of the cosmos that is invisible to the light telescopes in use today.

Not only will they be able to investigate black holes and strange objects known as neutron stars (giant suns that have collapsed to the size of cities), they should also be able to "look" much deeper into the Universe - and thus farther back in time. It may even be possible eventually to sense the moment of the Big Bang.


Read the full article here:
http://www.bbc.com/news/science-environment-35524440

The Universal Web

I was very excited to see this story in the news today about how astronomers have, for the first time ever, obtained actual photographic proof of dark matter and have presented their findings in Nature.com, an international weekly journal of science. They have seen, thanks to the intense glow of a quasar, the underlying structure of the universe itself! And that structure is, of course, a web. The photographic evidence looks like neurons in the human brain. We are all part of a web, a net. This could end up explaining a lot, and perhaps proving some ideas that are considered "metaphysical." They even have proof of "dark galaxies!" Th implications are staggering.

Cosmic 'web' seen for first time
By Simon Redfern Reporter, BBC News

The hidden tendrils of dark matter that underlie the visible Universe may have been traced out for the first time.

Cosmology theory predicts that galaxies are embedded in a cosmic web of "stuff", most of which is dark matter.

Astronomers obtained the first direct images of a part of this network, by exploiting the fact that a luminous object called a quasar can act as a natural "cosmic flashlight".

Details of the work appear in the journal Nature.

The quasar illuminates a nearby gas cloud measuring two million light-years across.

And the glowing gas appears to trace out filaments of underlying dark matter.

The quasar, which lies 10 billion light-years away, shines light in just the right direction to reveal the cold gas cloud.

For some years, cosmologists have been running computer simulations of the structure of the universe to build the "standard model of cosmology".

They use the cosmic microwave background, corresponding to observations of the very earliest Universe that can be seen, and recorded by instruments such as the Planck space observatory, as a starting point.

Their calculations suggest that as the Universe grows and forms, matter becomes clustered in filaments and nodes under the force of gravity, like a giant cosmic web.

The new results from the 10-metre Keck telescope in Hawaii, are reported by scientists from the University of California, Santa Cruz and the Max Planck Institute for Astronomy in Heidelberg.

They are the first direct observations of cold gas decorating such cosmic web filaments.

The cosmic web suggested by the standard model is mainly made up of mysterious "dark matter". Invisible in itself, dark matter still exerts gravitational forces on visible light and ordinary matter nearby.

Massive clumps of dark matter bend light that passes close by through a process called gravitational lensing, and this had allowed previous measurements of its distribution.

But it is difficult to use this method to see very distant dark matter, and cold ordinary matter remains tricky to detect as well.

The glowing hydrogen illuminated by the distant quasar in these new observations traces out an underlying filament of dark matter that it is attracted to it by gravity, according to the researchers' analysis.

BBC News/ Science article:
http://www.bbc.co.uk/news/science-environment-25809967

Original article:
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12898.html

Older and Slower! Now With More Dark Matter!

(CNN) -- How cute was our universe as a baby? We now know better than ever: The picture of our early universe just got sharper and tells scientists with greater precision many important facts about how the universe evolved.

This new photogenic moment, released Thursday, comes courtesy of the European Space Agency's Planck space telescope, which detects cosmic microwave background radiation -- the light left over from the Big Bang. Scientists used data from Planck to create an artificially colored map of temperature variations across the sky in the early universe, in more detail than ever before.

"It's a big deal," said Charles Lawrence, Planck project scientist at NASA's Jet Propulsion Laboratory, in a news briefing. He added, "We can tie together a whole range of phenomena that couldn't be tied together so well before, and the sum total of that, the impact, is felt in many, many ways."

The light is technically from 380,000 years after the Big Bang, but that's still infancy when you consider that, according to the new data, the age of the universe is about 13.8 billion years.

"By the matching observations from Planck to predictions from models, we can assemble a surprisingly detailed picture of the universe as it was one nano-nano-nano-nanosecond after the Big Bang," said Marc Kamionkowski, professor of physics and astronomy at John Hopkins University.

Kamionkowski compared the Planck map to the Human Genome Project in terms of its importance for cosmology.

After analyzing the new data, scientists now believe that the universe is about 100 million years older than they thought.

The universe's light started out as a white hot glow and would have been blindingly bright if anyone had been around to see it, Lawrence said.

But since the Big Bang, that hot light has cooled significantly, and the universe itself has expanded by a factor of 1,100. The light has cooled so much that we can't see it, but Planck can detect subtle variations in temperature, which give scientists a wealth of information. By subtle, we mean about one-hundred-millionth of a degree.

The colors in the temperature map image that scientists released Thursday were arbitrarily chosen to show these intensity variations, Lawrence said. Red means a little bit warmer than average, blue means cooler than average, and white is average.

Planck data also suggest that our universe has more dark matter than previously thought. A full 26.8% appears to be dark matter, an invisible phenomenon that scientists have only been able to detect indirectly; experiments both in space and at the Large Hadron Collider are hoping to pin it down.

It appears that ordinary matter -- all of the stuff that we can see, such as planets and stars -- makes up only 4.9% of all the universe.

The rest of the universe is an even more mysterious phenomenon called dark energy, which has also never been detected and appears to be in less abundance than researchers thought.

Scientists said the rate at which the universe is expanding, based on these observations, is 67.15 kilometers per second per megaparsec, a unit of vast distance in space (1 megaparsec = 3.3 million light years). That's significantly less than what had been calculated previously (73.8 km/sec/Mpc). This number, known as the Hubble constant, describes the acceleration of the stretching of spacetime.

The discrepancy between these Hubble constants will likely attract a lot of attention in the scientific community and is one of the most exciting parts of the new data, said Martin White, a scientist with the Planck mission based at the University of California, Berkeley.

"The hope would be that this is actually pointing toward some deficiency in the models, or some extra physics that we're not aware of, and maybe spark a whole new research direction," White said.

One theory that could be explored is that the nature of dark energy, which scientists think is causing the accelerated expansion of the universe, is different from the simplest human-calculated models. Is dark energy increasing with time over some volume of space? That's a radical theory, though, White said, and there are other possibilities.

Another anomaly of these results is that temperature fluctuations are not uniform across the sky map. There are more variations in one direction than in another.

"Perhaps we could say that our universe has thrown us a curve ball, and it rarely fails to surprise us," said Krzysztof Gorski, Planck scientist at NASA's Jet Propulsion Laboratory.

Scientists ran 10 million computer simulations and chose from among them the best match to the new data, White said. Out of those, they found a good match describing important statistics about the universe.

The Planck telescope is aboard a spacecraft that launched in May 2009. It is not circling the Earth but orbits a point in the Sun-Earth system called the second Lagrange point.

The Planck mission helps to nail down many of the parameters that other experiments must know to explore aspects of the universe, such as its expansion history, White said.

New analyses are based on the first 15.5 months of data from this mission, which is run principally by the European Space Agency. NASA is a partner of the project.

Planck represents the third generation of attempts to map the cosmic microwave background. The first was COBE, launched in 1989, followed by WMAP, launched in 2001. Comparing the resulting maps shows just how much better the maps have gotten with each successive satellite.

"This is a beautiful illustration of how science works," Lawrence said. "Make a measurement, learn from it, make a better measurement, learn from it."

By Elizabeth Landau
http://www.cnn.com/2013/03/21/tech/innovation/universe-planck-map/index.html?hpt=hp_c3

Proof Of Dark Matter!

This has been an amazing week for science! A new particle was announced, and now we have proof of dark matter!

Reported by Rachel Bayliss at COSMOS on-line:

LONDON: The fundamental ‘cosmic web’ of dark matter throughout the universe has finally been observed from Earth, confirming theories of how the universe was shaped.

“This result is a resounding confirmation of a key prediction of structure formation in the universe,” said Jörg Dietrich from University Observatory Munich, Germany, and lead author of the study published in Nature today.

“Not only did we for the first time see a dark matter filament directly, we also confirmed that it’s total mass [dark matter plus normal matter] and the amount of hot gas are in agreement with predictions.”

Galaxy clusters Abell 222 and Abell 223 connected by dark matter filament.

Yellow contours and blue shading are indicative of matter density.

Credit: Jörg Dietrich, University of Michigan/University Observatory Munich

DARK MATTER
Large cosmic structures, such as galaxies, exhibit gravitational affects that cannot be justified by the amount of normal matter present in the universe. A principle exists to describe this behavior and is known as the cold-dark-matter model, and it is the foundation of modern cosmology.

Within the model, vast quantities of dark matter, moving much slower than the speed of light (cold), must exist to explain the gravitational affects seen on normal matter.

As the name implies, dark matter cannot be observed in the traditional sense as it does not emit or absorb light at any significant level. However, its presence can be detected.

GRAVITATIONAL LENSING
“The technique we used is gravitational lensing,” said Dietrich. This is where light from, for example, a distant galaxy, is deflected and bent by huge gravitational fields generated by other similarly large objects. “It was widely believed that with current telescopes we would not be able to image dark matter filament with gravitational lensing.”

Dietrich and his team devised a method to boost the lensing signal sufficiently so that the dark matter filament between two clusters of galaxies could be observed with an 8m ground-based telescope.
“The key ingredient that made this result possible, is that we decided to study a very peculiar system of two massive galaxy clusters,” he said. These are called Abell 222 and Abell 223.

“Gravitational lensing is now allowing us to see parts of the universe that were previously invisible,” said astrophysicist Joanna Dunkley, from the University of Oxford, England, who was not involved in the study. “We already have plenty of indirect evidence that galaxy clusters trace a cosmic web of dark matter, but seeing this directly is an important step forward.”

THE COSMIC WEB
She added: “Our standard picture of cosmology tells us that filaments of invisible matter thread through the universe, and this bridge of dark matter connecting two clusters is exactly what we would expect.”

The research confirms that galaxy clusters form at the intersections of these vast filaments of dark matter.

Keen to develop this ground-breaking research further, Dietrich said, “We now want to study the interplay of dark matter density and galaxy population to get a better understanding of the mechanism that transforms galaxies from blue, star-forming spiral galaxies – which are the most common galaxies in filament – to red elliptical galaxies, which are the majority of galaxies in galaxy clusters.”

“The dark matter web makes up about a quarter of the universe,” Dunkley explained. “Being able to measure its morphology should help tell us more about how galaxies and clusters were formed, and may even give us a clue about what the dark matter itself is.” This in itself is a question that has been fascinating scientists for decades.

This research states that the underlying dark matter structure of the universe could comprise over half of all matter in existence. So developing it further is a must if scientists are to understand the elementary nature of the universe.

“We need to observe the lensing signal of more filaments to understand how special the one we found is,” Dietrich said. This will involve both in-depth statistical analysis of thousands of galaxy clusters, and a satellite mission to increase the possibilities of directly observing dark matter filaments.

http://www.cosmosmagazine.com/news/5765/scientists-shine-light-dark-matter

One Step Closer To Dark Matter

Astronomers have created a new, incredibly detailed map of dark matter by using the Hubble Space Telescope to peer through a huge cluster of galaxies as if it were a cosmic magnifying glass.
Though invisible, dark matter makes its presence known through its gravitational tug on normal stuff. Scientists now calculate that dark matter could make up 80 percent of all the matter in the universe.
The new dark matter map could reveal secrets not just about dark matter, but about its equally enigmatic sibling, dark energy. This is the name given to the perplexing force that is pulling against gravity, causing the universe to balloon in size ever more rapidly.
The dark matter map was created with observations from the Hubble telescope of a large galaxy cluster called Abell 1689, located 2.2 billion light-years from Earth. This cluster is famous as a stunning example of gravitational lensing – a phenomenon predicted by Einstein that happens when massive objects warp the space-time around them, causing even light to travel on a bent path when it passes by.
When astronomers look at Abell 1689, they can see distorted pictures of the galaxies that lie beyond it in our line of sight: As those galaxies' light travels from them to us, it passes through Abell 1689 and is bent and magnified.
By studying this so-called lensing effect, scientists can deduce the mass that is causing the warping.
Astronomer Dan Coe of NASA's Jet Propulsion Laboratory in Pasadena, Calif., and Edward Fuselier of the United States Military Academy at West Point teamed up to apply a new mathematical formulation to Hubble observations of Abell 1689. The result is the most accurate, detailed calculation so far of the cluster's mass distribution, including the mass that can't be accounted for by the visible matter – meaning, the dark matter.
"The lensed images are like a big puzzle," Coe said. "Here we have figured out, for the first time, a way to arrange the mass of Abell 1689 such that it lenses all of these background galaxies to their observed positions."

Above: the new map of dark matter

12 November 2010
01:29 pm ET

Clara Moskowitz
SPACE.com Senior Writer
space.com