The Largest void in universe Discovered


Hubble image of MACS J0717

Astronomers have detected the universe’s largest known cosmological supervoid in the Southern constellation of Eridanus.  Spanning some 1.8 billion light years !!!!!!!

(1 Light Years ~ 9 Trillion Kilometer)

It might be the single largest structure ever in the universe, and the only sign of it is nothing – just empty space 1.8 billion light years across. That’s 18,000 times larger than our entire galaxy.

the team remains mainly baffled as to why such an extensive void — in which the “density of galaxies is much lower than in the known universe” — could have actually arisen.

“This supervoid is certainly rare,” Greg Aldering, a cosmologist at Lawrence Berkeley National Lab in California, told Forbes.  “Underdense by about 30 percent, it’s not completely empty.  But what’s rare is the [spatial] extent of this void itself.”

Source : Forbes

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Hubble Space Telescope turns 25 and Here are some of the Most Amazing Pictures Taken by it


Hubble Space Telescope marks 25th anniversary in orbit this week. So, There are some  best images taken by Hubble Space Telescope during its 25 years journey. These Images are 100% real and contains no CGI

Hubble has traveled 3.4 billion miles, circling Earth nearly 137,000 times and making more than 1.2 million observations of more than 38,000 celestial objects, according to the Space Telescope Science Institute in Baltimore. The most distant objects spotted by Hubble — primitive galaxies — are some 13 billion light-years away and date to within 400 million or so years of the universe’s origin, known as the Big Bang.

Hubble provides an average of 829 gigabytes of archival data every month, according to the institute. Altogether, Hubble has produced more than 100 terabytes of data.

Some of the images have description about it. if anyone wants to read image description just click that image. and  Enjoy……

Image Credit : hubblesite.org

Source:Fox news

What Is Dark Matter? Colliding Galaxy Clusters May Help Find Answer


Dark matter is a hypothetical kind of matter that cannot be seen with telescopes but accounts for most of the matter in the universe.  Dark matter is estimated to constitute 84.5% of the total matter in the universe. It has not been detected directly, making it one of the greatest mysteries in modern astrophysics.

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Hubble Image of Galactic Collision 

A study of 72 large cluster collisions shows how dark matter in galaxy clusters behaves when they collide.

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Image Showing How two Galaxies Collides

Astronomers have used data from NASA’s Hubble Space Telescope and the Chandra X-ray Observatory to find that dark matter interacts with itself less than previously thought. In an effort to learn more about dark matter, astronomers observed how galaxy clusters collide with each other — an event that could hold clues about the mysterious invisible matter that makes up most of the mass of the universe.

As part of a new study, published in the journal Science on Thursday, researchers used the Hubble telescope to map the distribution of stars and dark matter after a collision. They also used the Chandra observatory to detect the X-ray emission from colliding gas clouds.

“Dark matter is an enigma we have long sought to unravel,” John Grunsfeld, assistant administrator of NASA’s Science Mission Directorate in Washington, said in a statement. “With the combined capabilities of these great observatories, both in extended mission, we are ever closer to understanding this cosmic phenomenon.”

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Here are images of six different galaxy clusters taken with NASA’s Hubble Space Telescope (blue) and Chandra X-ray Observatory (pink) in a study of how dark matter in clusters of galaxies behaves when the clusters collide. A total of 72 large cluster collisions were studied.  NASA and ESA

According to scientists, galaxy clusters are made of three main components — galaxies, gas clouds and dark matter. During collisions, the gas clouds bump into each other and gradually slow down. Galaxies, on the other hand, are much less affected by this process, and because of the huge gaps between the stars within them, galaxies do not slow each other down.

“We know how gas and stars react to these cosmic crashes and where they emerge from the wreckage,” David Harvey of the École Polytechnique Fédérale de Lausanne in Switzerland, and the study’s lead author, said in the statement. “Comparing how dark matter behaves can help us to narrow down what it actually is.”

The researchers studied 72 large galaxy cluster collisions and found that, like galaxies, the dark matter continued straight through the collisions without slowing down much, meaning that dark matter do not interact with visible particles.

“There are still several viable candidates for dark matter, so the game is not over. But we are getting nearer to an answer,” Harvey said.

Source : IBT times

Hubble Captures ‘Happy Face’ of Universe


A smiling lens

Hubble Takes a Amazing Picture which seems like Happy Face in the Space.

Of course, this is neither a miracle nor a edited picture.

The reason behind this ‘Happy face’ is very Complex Phenomena called Gravitational Lensing. The Eyes of the face are two Galaxies but Face’s smile is due to gravity. Gravitational lensing is one of the most fascinating thing in Physics and astronomy.

This picture shows the true power of gravity. The gravity of these massive galaxies are so intense that they even distort the space-time create this amazing lens effect. The light itself distorted and gives the magnified view of galaxies.

Some astronomer believes that it is because of Dark matter, an unknown matter which is yet to be discover. These images are the strong evidence of dark matter but further research and experiments are needed to entirely prove their existence.

Hubble takes many images which shows gravitational lensing

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Wormhole to another galaxy may exist in Milky Way


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A giant doorway to another galaxy may exist at the centre of the Milky Way, a study suggests.

Scientists believe that dark matter at the centre of our galaxy could sustain a wormhole that we could travel through.

Wormholes are areas where space and time are being bent so that distant points are now closer together.

Einstein predicted them in his theory of General Relativity but nobody knows how they could be held open so that someone could travel through. Most scientists believe that It is extremely unlikely they could exist naturally in the universe. It would take a huge mass, like a Neutron star, to create a bend in time which could bend space time enough to meet another tunnel on the other side. No natural examples have ever been detected.

“If we combine the map of the dark matter in the Milky Way with the most recent Big Bang model to explain the universe and we hypothesise the existence of space-time tunnels, what we get is that our galaxy could really contain one of these tunnels, and that the tunnel could even be the size of the galaxy itself,” said Professor Paulo Salucci.

“But there’s more. We could even travel through this tunnel, since, based on our calculations, it could be navigable. Just like the one we’ve all seen in the recent film ‘Interstellar“‘.

He said the research was surprisingly close to what was depicted in director Christopher Nolan’s movie, for which theoretical physicist Kip Thorne provided technical assistance.

“What we tried to do in our study was to solve the very equation that the astrophysicist ‘Murph’ was working on,” said Prof Salucci. “Clearly we did it long before the film came out.”

Wormhole, conceptual artwork

 Wormholes bend space-time to allow distant regions to meet

Any wormholes existing in nature have previously been assumed to be microscopic pinpricks in the fabric of space-time.

But the one possibly lying at the centre of the Milky Way would be large enough to swallow up a spaceship and its crew.

Prof Salucci added: “Obviously we’re not claiming that our galaxy is definitely a wormhole, but simply that, according to theoretical models, this hypothesis is a possibility.”

Other “spiral” galaxies similar to the Milky Way – like its neighbour Andromeda – may also contain wormholes, the scientists believe.

Theoretically it might be possible to test the idea by comparing the Milky Way with a different type of nearby galaxy, such as one of the irregular Magellanic Clouds.

In their paper, the scientists write: “Our result is very important because it confirms the possible existence of wormholes in most of the spiral galaxies ..

“Dark matter may supply the fuel for constructing and sustaining a wormhole. Hence, wormholes could be found in nature and our study may encourage scientists to seek observational evidence for wormholes in the galactic halo region.”

The theory was published in the journal Annals of Physics.

Source : Telegraph

Forget dark matter, STRANGE matter could be lurking somewhere in the universe


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  • Scientists at the National Institute for Space Research in Brazil say an undiscovered type of matter could be found in neutron stars
  • Here matter is so dense that it could be ‘squashed’ into strange matter
  • This would create an entire ‘strange star’ – unlike anything we have seen
  • However, the exact properties of strange matter are unknown
  • If it exists, though, it could help scientists discover ripples in space-time known as gravitational waves

Neutron stars are among the densest objects in the universe – just a spoonful of matter from one of them would weigh more than the moon.

But inside these remarkable stellar objects, which are no bigger than a city on Earth, a remarkable process might be taking place.

Scientists have revealed their matter might become so squashed that it turns into ‘strange matter’ – and observing so-called strange stars could unlock some of the secrets of the universe.

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Scientists at the National Institute for Space Research in Brazil say an undiscovered type of matter could be found in neutron stars (illustration shown). Here matter is so dense that it could be ‘squashed’ into strange matter. This would create an entire ‘strange star’ – unlike anything we have seen

The latest theory was proposed by Dr Pedro Moraes and Dr Oswaldo Miranda, both of the National Institute for Space Research in Brazil.

They say that some types of neutron stars might be made of a new type of matter called strange matter.

What the properties of this matter would be, though, are unknown – but it would likely be a ‘liquid’ of several types of sub-atomic particles.

Source: daily mail

New Signal May Be Evidence of Dark Matter


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Scientists say they may have discovered a possible dark matter signal coded in the X-rays emanating from two bright objects in the sky.

The findings, set to be published next week in Physical Review Letters, could offer tangible evidence for the existence of dark matter — and help researchers build new tools to search for and study this mysterious stuff.

When it comes to matter in the universe, dark matter is like a backroom political power broker: You never see it, but behind the scenes, it’s been throwing its weight around. The effects of its gravitational influence can be seen in the large-scale structures of the cosmos. Dark matter makes up about 84.5% of the matter in the universe while all the stuff we actually see — stars, galaxies, planets, ourselves — makes up the remaining 15.5%. The enormous galaxies and clusters of galaxies that populate the universe are bantamweights compared to the massive, unseen dark matter ‘halos’ that anchor them.

Dark matter’s formidable gravitational influence is the only way that the strange stuff can be detected, because it’s invisible — it does not interact with light. Physicists have no idea what it’s made of, although they’ve looked for it by building detectors in underground former gold mines, sending satellites into space and other methods.

But now, a team led by researchers at Leiden University in the Netherlands and the École Polytechnique Fédérale de Lausanne in Switzerland say they’ve discovered a signal that could be a sign of dark matter.

The scientists looked at X-ray emissions coming from the Andromeda galaxy and the Perseus galaxy cluster, collected by the European Space Agency’s XMM-Newton space telescope. After accounting for all the light particles (called photons) emanating from known sources in the Andromeda galaxy, they were left with a strange set of photons that had no known source. The found the same light signature emanating from the Perseus cluster. And when they turned their attention to the Milky Way, they found signs of this signal in our home galaxy, as well.

“It is consistent with the behavior of a line originating from the decay of dark matter particles,” the authors wrote in a pre-print of the study.

This weird light signal, they think, could be coming from the destruction of a hypothetical particle called a sterile neutrino (which, if it exists, might help explain dark matter). But it’s going to take a lot of follow-up study to determine whether this signal is a scientific breakthrough or an anomalous blip.

“Future detections or non-detections of this line in multiple astrophysical targets may help to reveal its nature,” the study authors wrote.

Japan’s upcoming Astro-H mission, they said, might allow them to do just that.

Source :Science Tech Today

Is Dark Energy Evaporating Dark Matter?


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cientists at the University of Rome and Portsmouth recently published a paper which describes dark matter slowly being engulfed by dark energy.

Dark matter is almost completely undetectable matter that astronomers and cosmologists have calculated to exist within our universe, hence the name “dark”. Whereas dark energy is an accepted model of energy that permeates all matter and space, and is responsible for the acceleration of the expansion of the universe (to find out more about the two, click on the links above)

Why are they of interest now?

In the paper, the cosmologists discuss how recent astronomical data favours the idea that dark energy grows as it interacts with dark matter, which can help explain the mechanics of the expansion of the universe.

“If the dark energy is growing and dark matter is evaporating we will end up with a big, empty, boring universe with almost nothing in it,” said the Director of Portsmouth’s Institute of Cosmology and Gravitation, Professor David Wands.

Professor Wands continues by stating that “Dark matter provides a framework for structures to grow in the Universe. The galaxies we see are built on that scaffolding and what we are seeing here, in these findings, suggests that dark matter is evaporating, slowing that growth of structure,”.

How does this play a role in the understanding of our universe?

As our understanding of the universe changes, so does our approach in pursuing more knowledge about its every aspect. In 1998, researchers observing distant supernovae found that they were fainter than expected. The most accepted explanation for the variance is that the light emitted from the supernovae traveled a greater distance than theorists had predicted. This observation lead to the conclusion that space must have expanded at an accelerating rate as it traveled. The phenomenon was later attributed to the existence of dark energy, which completely revolutionized the scientific community’s way of looking at the structure of the universe, and in essence, the very foundation of our existence.

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If dark energy continues its dominance in the Universe, every galaxy beyond our neighborhood will one day no longer be visible

Now, researchers believe that it is the evaporation of dark matter that can explain why the growth of cosmic structures, such as galaxies and clusters of galaxies, seems to be slower than expected.

The availability of more data allows researchers such as Professor Wands, to examine the mechanics and interactions of various cosmic phenomena more precisely.

“Much more data is available now than was available in 1998 and it appears that the standard model is no longer sufficient to describe all of the data. We think we’ve found a better model of dark energy,” Wands continues, “However there is growing evidence that this simple model cannot explain the full range of astronomical data researchers now have access to; in particular the growth of cosmic structure, galaxies and clusters of galaxies, seems to be slower than expected”.

The paper itself was published by the American Physical Society, and although it looks very interesting, one must keep in mind that dark energy and dark matter is a subject in which very little is understood. As more data becomes available, a finer structure of our universe can be developed, which cannot be possible without the researchers such as Prof. Wands, Dr. Marco Bruni and their research students.

Source : from quarks to quasars

Universe may face a darker future


Artist’s impression of exocomets around Beta Pictoris

New research offers a novel insight into the nature of dark matter and dark energy and what the future of our Universe might be.

Researchers in Portsmouth and Rome have found hints that dark matter, the cosmic scaffolding on which our Universe is built, is being slowly erased, swallowed up by dark energy.

The findings appear in the journal Physical Review Letters, published by the American Physical Society. In the journal cosmologists at the Universities of Portsmouth and Rome, argue that the latest astronomical data favours a dark energy that grows as it interacts with dark matter, and this appears to be slowing the growth of structure in the cosmos.

Professor David Wands, Director of Portsmouth’s Institute of Cosmology and Gravitation, is one of the research team.

He said: “This study is about the fundamental properties of space-time. On a cosmic scale, this is about our Universe and its fate.

“If the dark energy is growing and dark matter is evaporating we will end up with a big, empty, boring Universe with almost nothing in it.

“Dark matter provides a framework for structures to grow in the Universe. The galaxies we see are built on that scaffolding and what we are seeing here, in these findings, suggests that dark matter is evaporating, slowing that growth of structure.”

Cosmology underwent a paradigm shift in 1998 when researchers announced that the rate at which the Universe was expanding was accelerating. The idea of a constant dark energy throughout space-time (the “cosmological constant”) became the standard model of cosmology, but now the Portsmouth and Rome researchers believe they have found a better description, including energy transfer between dark energy and dark matter.

Research students Valentina Salvatelli and Najla Said from the University of Rome worked in Portsmouth with Dr Marco Bruni and Professor Wands, and with Professor Alessandro Melchiorri in Rome. They examined data from a number of astronomical surveys, including the Sloan Digital Sky Survey, and used the growth of structure revealed by these surveys to test different models of dark energy.
Professor Wands said: “Valentina and Najla spent several months here over the summer looking at the consequences of the latest observations. Much more data is available now than was available in 1998 and it appears that the standard model is no longer sufficient to describe all of the data. We think we’ve found a better model of dark energy.

“Since the late 1990s astronomers have been convinced that something is causing the expansion of our Universe to accelerate. The simplest explanation was that empty space – the vacuum – had an energy density that was a cosmological constant. However there is growing evidence that this simple model cannot explain the full range of astronomical data researchers now have access to; in particular the growth of cosmic structure, galaxies and clusters of galaxies, seems to be slower than expected.”
Professor Dragan Huterer, of the University of Michigan, has read the research and said scientists need to take notice of the findings.

He said: “The paper does look very interesting. Any time there is a new development in the dark energy sector we need to take notice since so little is understood about it. I would not say, however, that I am surprised at the results, that they come out different than in the simplest model with no interactions. We’ve known for some months now that there is some problem in all data fitting perfectly to the standard simplest model.”

Evidence Builds for Dark Matter Explosions at the Milky Way’s Core


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This Fermi map of the Milky Way center shows an overabundance of gamma-rays (red indicates the greatest number) that cannot be explained by conventional sources.

So far, dark matter has evaded scientists’ best attempts to find it. Astronomers know the invisible stuff dominates our universe and tugs gravitationally on regular matter, but they do not know what it is made of. Since 2009, however, suspicious gamma–ray light radiating from the Milky Way’s core—where dark matter is thought to be especially dense—has intrigued researchers. Some wonder if the rays might have been emitted in explosions caused by colliding particles of dark matter. Now a new gamma-ray signal, in combination with those already detected, offers further evidence that this might be the case.

One possible explanation for dark matter is that it is made of theorized “weakly interacting massive particles,” or WIMPs. Every WIMP is thought to be both matter and antimatter, so when two of them meet they should annihilate on contact, as matter and antimatter do. These blasts would create gamma-ray light, which is what astronomers see in abundance at the center of our galaxy in data from the Fermi Gamma-Ray Space Telescope. The explosions could also create cosmic-ray particles—high-energy electrons and positrons (the antimatter counterparts of electrons)—which would then speed out from the heart of the Milky Way and sometimes collide with particles of starlight, giving them a boost of energy that would bump them up into the gamma-ray range. For the first time scientists have now detected light that matches predictions for this second process, called inverse Compton scattering, which should produce gamma rays that are more spread out over space and come in a different range of energies than those released directly by dark matter annihilation.

“It looks pretty clear from their work that an additional inverse Compton component of gamma rays is present,” says Dan Hooper, an astrophysicist at the Fermi National Accelerator Laboratory who was not involved in the study, but who originally pointed out that a dark matter signal might be present in the Fermi telescope data. “Such a component could come from the same dark matter that makes the primary gamma-ray signal we’ve been talking about all of these years.” University of California, Irvine scientists Anna Kwa and Kevork Abazajian presented the new study October 23 at the Fifth International Fermi Symposium in Nagoya, Japan and submitted their paper to Physical Review Letters.

None of the intriguing gamma-ray light is a smoking gun for dark matter. Other astrophysical processes, such as spinning stars called pulsars, can create both types of signal. “You can make models that replicate all this with astrophysics,” Abazajian says. “But the case for dark matter is the easiest, and there’s more and more evidence that keeps piling up.”

The official Fermi telescope team has long been cautious about drawing conclusions on dark matter from their data. But at last week’s symposium, the group presented its own analysis of the unexplained gamma-ray light and concluded that although multiple hypotheses fit the data, dark matter fits best. “That’s huge news because it’s the first time they’ve acknowledged that,” Abazajian says. Simona Murgia, an astrophysicist at the University of California, Irvine and a member of the Fermi collaboration’s galactic-center analysis team, presented the team’s findings. She says the complexity of the galactic center makes it difficult to know for sure how the excess of gamma rays arose and whether or not the light could come from mundane “background” sources. “It is a very interesting claim,” she says of Abazajian’s analysis. “However, detection of extended excesses in this region of the sky is complicated by our incomplete understanding of the background.”

The dark matter interpretation would look more likely if astronomers could find similar evidence of WIMP annihilation in other galaxies, such as the two dozen or so dwarf galaxies that orbit the Milky Way. “Extraordinary claims require extraordinary evidence, and I think a convincing claim of discovery would probably require a corresponding signal in another location—or by a non-astrophysical experiment—as well as the galactic center,” says Massachusetts Institute of Technology astrophysicist Tracy Slatyer, who has also studied the Fermi data from the Milky Way’s center.

Non-astrophysical experiments include the handful of so-called direct-detection experiments on Earth, which aim to catch WIMPs on the extremely rare occasions when they bump into atoms of normal matter. So far, however, none of these has found any evidence for dark matter. Instead they have steadily whittled away at the tally of possible types of WIMPs that could exist.

Other orbiting experiments, such as the Alpha Magnetic Spectrometer (AMS) on the International Space Station, which detects cosmic rays, have also failed to find convincing proof of dark matter. In fact, the AMS results seem to conflict with the most basic explanations linking dark matter to the Fermi observations. “Most people would agree that there is something rather unexpected happening at the galactic center, and it would be tremendously exciting if it turns out to be a dark matter annihilation signal,” says Christoph Weniger of the University of Amsterdam, another astrophysicist who has studied the Milky Way’s core. “But we have to confirm this interpretation by finding corroborating evidence in other independent observations first. Much more work needs to be done.”

Source : scientificamerican