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Fast radio burst tracked to faraway galaxy

Fast radio burst tracked to faraway galaxy | Amazing Science | Scoop.it

For the first time, scientists have tracked the source of a "fast radio burst" - a fleeting explosion of radio waves which, in this case, came from a galaxy six billion light-years away. The cause of the big flash, only the seventeenth ever detected, remains a puzzle, but spotting a host galaxy is a key moment in the study of such bursts. It also allowed the team to measure how much matter got in the way of the waves and thus to "weigh the Universe". Their findings are published in Nature.

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Shafique Miraj Aman's curator insight, February 29, 11:30 PM

A e s t h e t i c a l l y                              A p p e a l i n g

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Gravitational waves: How LIGO forged the path to victory

Gravitational waves: How LIGO forged the path to victory | Amazing Science | Scoop.it
Historic discovery of ripples in space-time meant ruling out the possibility of a fake signal.


At 11:53 a.m. local time on 14 September 2015, an automated e-mail appeared in the inbox of Marco Drago, a physicist at the Max Planck Institute for Gravitational Physics in Hannover, Germany. It contained links to two plots, each showing a wave shaped like a bird’s chirp that emerged suddenly from a noisy background and ended in a crash.


It was a signal that Drago had been trained to spot and that the US-led Advanced Laser Interferometer Gravitational-Wave Observatory (LIGO) that he works on was built to detect: the signature ripples in space-time produced when two black holes collide to form a single gravitational sink. No one had ever directly detected gravitational waves before, nor a black-hole merger. The plots, one from each of LIGO’s twin detectors in Washington state and Louisiana, would go on to make history.


On 11 February, the LIGO collaboration announced that it had made the first detection of gravitational waves from a black-hole merger that occurred about 400 million parsecs (1.3 billion light years) from Earth. It was just over 100 years after Albert Einstein predicted such waves as part of his general theory of relativity. “We did it!” David Reitze, the executive director of the LIGO Laboratory, said at a press conference in Washington DC.

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Einstein’s Gravitational Waves Detected Originating from Merging Black Holes 1.3 Billion Years Ago

Einstein’s Gravitational Waves Detected Originating from Merging Black Holes 1.3 Billion Years Ago | Amazing Science | Scoop.it
Today, scientists announced that, for the first time in history, gravitational waves have been detected.

Gravitational waves are ripples in spacetime throughout the universe. What’s truly remarkable about this discovery is that Albert Einstein predicted the existence of gravitational waves 100 years ago, but scientists have never been able to detect them, until now.

The discovery came out of the U.S. based Laser Interferometer Gravitational Wave Observatory (LIGO). The mission of LIGO was to directly measure gravitational waves. In order to do that, LIGO scientists needed to construct the most precise measuring device the world had ever seen.

The LIGO project, which began in 1992, was the largest scientific investment the National Science Foundation (NSF) has ever made.

At an NSF press conference this morning, LIGO Laboratory Executive Director, David Reitze, said “This was a scientific moon shot. And we did it – we landed on the moon.”


LIGO consists of two 4 kilometer (2.5 mile) tunnels located in Louisiana and the state of Washington. Because gravitational waves stretch space in one direction and compress space in the other, LIGO was designed to measure changes in length across large land distances. If they could detect a stretch of land in the LIGO tunnels in one direction and compression in the other, they could theoretically detect a gravitational wave.


The “ruler” that scientists used to measure these tunnel lengths was the speed of light. The speed of light is constant, so LIGO can determine the length of the tunnels by measuring the time it takes for a laser to bounce from one end of the tunnel to the other.


Gravitational waves are created when masses accelerate. Measured back on September 14th, 2015, the gravitational wave signal that the LIGO scientists detected matches the exact signal they’d expect from two merging black holes accelerating at half the speed of light.


Reitze explained that the black holes that created this gravitational wave merged 1.3 billion years ago. It took that long for the wave to travel to the Earth. Each of the black holes were 30 times the mass of the sun and were accelerating at half the speed of light when they collided into each other. The ability to measure gravitational waves will open up an entirely new window for astronomy. Reitze explained that this will enable scientists to look at the universe in a new way.


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Ancient black holes can outshine entire galaxies

Ancient black holes can outshine entire galaxies | Amazing Science | Scoop.it

Quasars are extreme in almost every way. They can outshine their entire galaxies; their black holes can be billions of times more massive than the Sun; their temperatures reach tens of millions of degrees; and some of them fire jets of charged particles into space that can reach almost light speed. But before Schmidt realized that the first quasar, dubbed 3C 273, was something extraordinary, it had been a puzzle. It was one of many so-called radio galaxies that astronomers were discovering in the 1950s.


These galaxies produce radiation at radio wavelengths, and astronomers were busily cataloguing these radio signals and matching them with objects visible in the night sky at the locations of the signals. Generally, these radio galaxies appeared as faint smudges suggestive of a galaxy. The 3C 273 radio signal, though, overlapped with a bright point of light. The point looked like a star that happened to lie on the path between the 3C 273 source and Earth, and at first, that is what Schmidt thought it was.


But then he measured its spectra – how the light is split into its constituent colors – a basic piece of information that reveals an object's chemical composition and its distance. Spectra make a pattern of vertical lines, each glowing at specific wavelengths. 3C 273 had a pattern unlike any he had seen before. Normally,  it would be easy to identify the bright lines that represent a star's hydrogen gas. But in this case the spectrum was all over the place, and no one could figure out what it was. If it was a star, it was a strange one.


Schmidt started to write a paper describing the puzzling results. "While I was writing it, I looked at the spectrum again and suddenly I realised there was something regular about it," he would recall at a symposium commemorating the 50th anniversary of his discovery.

Because the Universe is expanding, objects that are further away from us are moving much faster than nearby objects. So by measuring a redshift, astronomers can calculate an object's speed and thus its distance.


But the redshift that Schmidt measured was much bigger than what anyone would expect for a star. "It was a stunning discovery because stars shouldn't do that," Schmidt said. The Milky Way is only about 100,000 light years across, while 3C 273 turned out to be two billion light years away – clearly much too far away to be one of our galaxy's stars.


To shine as bright as one from such a distance, 3C 273 has to be producing prodigious amounts of energy. But how? In 1969, Donald Lynden-Bell, an astronomer now at the University of Cambridge, had an idea: supermassive black holes. Centers of galaxies hosting supermassive black holes that devour gas and dust. Roughly 10% of all galaxies have some activity at their centres. They come in different flavours, producing radiation at various wavelengths. Some are stronger in ultraviolet, others produce more X-rays, radio waves, or far infrared. Quasars, which are seen in about 1% of galaxies, are the brightest of the bunch.

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Theorists propose a new method to probe the beginning of the universe

Theorists propose a new method to probe the beginning of the universe | Amazing Science | Scoop.it

How did the universe begin? And what came before the Big Bang? Cosmologists have asked these questions ever since discovering that our universe is expanding. The answers aren't easy to determine. The beginning of the cosmos is cloaked and hidden from the view of our most powerful telescopes. Yet observations we make today can give clues to the universe's origin. New research suggests a novel way of probing the beginning of space and time to determine which of the competing theories is correct.


The most widely accepted theoretical scenario for the beginning of the universe is inflation, which predicts that the universe expanded at an exponential rate in the first fleeting fraction of a second. However a number of alternative scenarios have been suggested, some predicting a Big Crunch preceding the Big Bang. The trick is to find measurements that can distinguish between these scenarios.


One promising source of information about the universe's beginning is the cosmic microwave background (CMB) - the remnant glow of the Big Bang that pervades all of space. This glow appears smooth and uniform at first, but upon closer inspection varies by small amounts. Those variations come from quantum fluctuations present at the birth of the universe that have been stretched as the universe expanded.


The conventional approach to distinguish different scenarios searches for possible traces of gravitational waves, generated during the primordial universe, in the CMB. "Here we are proposing a new approach that could allow us to directly reveal the evolutionary history of the primordial universe from astrophysical signals. This history is unique to each scenario," says coauthor Xingang Chen of the Harvard-Smithsonian Center for Astrophysics (CfA) and the University of Texas at Dallas.


While previous experimental and theoretical studies give clues to spatial variations in the primordial universe, they lack the key element of time. Without a ticking clock to measure the passage of time, the evolutionary history of the primordial universe can't be determined unambiguously.

"Imagine you took the frames of a movie and stacked them all randomly on top of each other. If those frames aren't labeled with a time, you can't put them in order. Did the primordial universe crunch or bang? If you don't know whether the movie is running forward or in reverse, you can't tell the difference," explains Chen.


This new research suggests that such "clocks" exist, and can be used to measure the passage of time at the universe's birth. These clocks take the form of heavy particles, which are an expected product of the "theory of everything" that will unite quantum mechanics and general relativity. They are named the "primordial standard clocks."


Subatomic heavy particles will behave like a pendulum, oscillating back and forth in a universal and standard way. They can even do so quantum-mechanically without being pushed initially. Those oscillations or quantum wiggles would act as clock ticks, and add time labels to the stack of movie frames in our analogy.


"Ticks of these primordial standard clocks would create corresponding wiggles in measurements of the cosmic microwave background, whose pattern is unique for each scenario," says coauthor Yi Wang of The Hong Kong University of Science and Technology. However, current data isn't accurate enough to spot such small variations.


Ongoing experiments should greatly improve the situation. Projects like CfA's BICEP3 and Keck Array, and many other related experiments worldwide, will gather exquisitely precise CMB data at the same time as they are searching for gravitational waves. If the wiggles from the primordial standard clocks are strong enough, experiments should find them in the next decade. Supporting evidence could come from other lines of investigation, like maps of the large-scale structure of the universe including galaxies and cosmic hydrogen.


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Harriet Rolfe's curator insight, June 1, 10:03 PM
One of the fundamental part of science is to challenge theories and collect data. I want to push my Year 10's to think beyond what they are taught and analyse multiple sources of data before they make up their mind
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What is 10 miles across, but powers an explosion brighter than the Milky Way?

What is 10 miles across, but powers an explosion brighter than the Milky Way? | Amazing Science | Scoop.it
Astronomers have spotted what may be the brightest supernova ever seen -- and discovered a mysterious object at its center.


Right now, astronomers are viewing a ball of hot gas billions of light years away that is radiating the energy of hundreds of billions of suns. At its heart is an object a little larger than 10 miles across. And astronomers are not entirely sure what it is. If, as they suspect, the gas ball is the result of a supernova, then it's the most powerful supernova ever seen.


In this week's issue of the journal Science, they report that the object at the center could be a very rare type of star called a magnetar--but one so powerful that it pushes the energy limits allowed by physics. An international team of professional and amateur astronomers spotted the possible supernova, now called ASASSN-15lh, when it first flared to life in June 2015.


Even in a discipline that regularly uses gigantic numbers to express size or distance, the case of this small but powerful mystery object in the center of the gas ball is so extreme that the team's co-principal investigator, Krzysztof Stanek of The Ohio State University, turned to the movie This is Spinal Tap to find a way to describe it.


"If it really is a magnetar, it's as if nature took everything we know about magnetars and turned it up to 11," Stanek said. For those not familiar with the comedy, the statement basically translates to "11 on a scale of 1 to 10."


The gas ball surrounding the object can't be seen with the naked eye, because it's 3.8 billion light years away. But it was spotted by the All Sky Automated Survey for Supernovae (ASAS-SN, pronounced "assassin") collaboration. Led by Ohio State, the project uses a cadre of small telescopes around the world to detect bright objects in our local universe.


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The Hourglass Nebula - Made of Hydrogen, Oxygen and Nitrogen, Ingredients of Life

The Hourglass Nebula - Made of Hydrogen, Oxygen and Nitrogen, Ingredients of Life | Amazing Science | Scoop.it

This is an image of MyCn18, a young planetary nebula located about 8,000 light-years away, taken with the Wide Field and Planetary Camera 2 (WFPC2) aboard the Hubble Space Telescope (HST). This Hubble image reveals the true shape of MyCn18 to be an hourglass withThe sands of time are running out for the central star of this hourglass-shaped planetary nebula.  With its nuclear fuel exhausted, this brief but spectacular closing phase of MyCn18 - better known as the Engraved Hourglass Nebula - occurs as its outer layers are ejected. Located 8,000 light-years away from Earth in the southern constellation Musca, the sun-like star's core is in the process of becoming a cooling, fading white dwarf.


Astronomers used the Hubble Space Telescope to make a series of images of planetary nebulae in the mid-1990s, including this one.

Delicate rings of colourful glowing gas - nitrogen-red, hydrogen-green, and oxygen-blue - outline the tenuous walls of the hourglass. 

The unprecedented sharpness of Hubble's image has revealed surprising details of the nebula ejection process.


And it is these that are helping scientists to resolve the outstanding mysteries of the complex shapes and symmetries of planetary nebula.

MyCn18 was discovered by Annie Jump Cannon and Margaret W Mayall during their research on an extended Henry Draper Catalogue, an astronomical star encyclopedia compiled between 1918 and 1924.


The astronomers described it as a small faint planetary nebula, but the march of technology allowed scientists Raghvendra Sahai and John Trauger of the Jet Propulsion Laboratory to capture this stunning image using Hubble in January 1996. MyCn18's hourglass shape is thought to have arisen from the expansion of a fast stellar wind within a slowly expanding cloud which is denser near its equator than its poles.


Life on Earth was made possible by the death of stars. Atoms like carbon and oxygen were expelled in the last few dying gasps of stars after their final supplies of hydrogen fuel were used up. How this star-stuff came together to form life is still a mystery, but scientists know that certain atomic combinations were necessary. Water – two hydrogen atoms linked to one oxygen atom -was vital to the development of life on Earth, and so NASA missions now search for water on other worlds in the hopes of finding life elsewhere. Organic molecules built mostly of carbon atoms are also thought to be important, since all life on Earth is carbon-based.


The most popular theories of the origin of life say the necessary chemistry occurred at hydrothermal vents on the ocean floor or in some sunlit shallow pool. However, discoveries in the past few years have shown that many of the basic materials for life form in the cold depths of space, where life as we know it is not possible.


After dying stars belch out carbon, some of the carbon atoms combine with hydrogen to form polycyclic aromatic hydrocarbons (PAHs). PAHs — a kind of carbon soot similar to the scorched portions of burnt toast — are the most abundant organic compounds in space, and a primary ingredient of carbonaceous chondrite meteorites. Although PAHs aren’t found in living cells, they can be converted into quinones, molecules that are involved in cellular energy processes. For instance, quinones play an essential role in photosynthesis, helping plants turn light into chemical energy.


The transformation of PAHs occurs in interstellar clouds of ice and dust. After floating through space, PAH soot eventually condenses into these "dense molecular clouds." The material in these clouds blocks out some but not all of the harsh radiation of space. The radiation that does filter through modifies the PAHs and other material in the clouds.


Infrared and radio telescope observations of the clouds have detected the PAHs, as well as fatty acids, simple sugars, faint amounts of the amino acid glycine, and over 100 other molecules, including water, carbon monoxide, ammonia, formaldehyde, and hydrogen cyanide.


The clouds have never been sampled directly — they’re too far away — so to confirm what is occurring chemically in the clouds, a research team led by Max Bernstein and Scott Sandford at the Astrochemistry Laboratory at NASA’s Ames Research Center set up experiments to mimic the cloud conditions.


In one experiment, a PAH/water mixture is vapor-deposited onto salt and then bombarded with ultraviolet (UV) radiation. This allows the researchers to observe how the basic PAH skeleton turns into quinones. Irradiating a frozen mixture of water, ammonia, hydrogen cyanide, and methanol (a precursor chemical to formaldehyde) generates the amino acids glycine, alanine and serine — the three most abundant amino acids in living systems.

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A First: Visible Light from a Black Hole Spotted by Telescope

A First: Visible Light from a Black Hole Spotted by Telescope | Amazing Science | Scoop.it

For the first time, astronomers have seen dim flickers of visible light from near a black hole, researchers with an international science team said. In fact, the light could be visible to anyone with a moderate-size telescope.


Scientists discovered accreting black holes in the Milky Way more than 40 years ago. Previous research suggested that the accretion disks of black holes can have dramatic effects on galaxies. For instance, streams of plasma known as relativistic jets that spew out from accreting black holes at near the speed of light can travel across an entire galaxy, potentially shaping its evolution. However, much remains unknown about how accretion works, since matter can behave in very complex ways as it spirals into black holes, said study lead author Mariko Kimura, an astronomer at Kyoto University in Japan, and her colleagues.


To learn more about the mysterious process of accretion, researchers in the new study analyzed V404 Cygni, a binary system composed of a black hole about nine times the mass of the sun and a companion star slightly less massive than the sun. Located about 7,800 light-years away from Earth in the constellation Cygnus, the swan, V404 Cygni possesses one of the black holes closest to Earth. After 26 years during which the system was dormant, astronomers detected an outburst of X-rays from V404 Cygni in 2015 that lasted for about two weeks. This activity from the accretion disk of V404 Cygni's black hole briefly made it one of the brightest sources of X-rays seen in the universe.


Following this outburst, the researchers detected flickering visible light from V404 Cygni, whose fluctuations varied over timescales of 100 seconds to 150 minutes. Normally, astronomers monitor black holes by looking for X-rays or gamma-rays.


"We find that activity in the vicinity of a black hole can be observed in optical light at low luminosity for the first time," Kimura told Space.com. "These findings suggest that we can study physical phenomena that occur in the vicinity of the black hole using moderate optical telescopes without high-spec X-ray or gamma-ray telescopes."

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Supernova shows up a fifth time due to gravity warps

Supernova shows up a fifth time due to gravity warps | Amazing Science | Scoop.it
A supernova that has already appeared four times is back for an encore.


 A scene-stealing supernova is back for an encore. After last year’s quadruple replay, supernova Refsdal has shown up a fifth time, thanks to the many meandering paths its light takes through an intervening galaxy cluster. The most recent appearance showed up in December in images taken by the Hubble Space Telescope. Astronomer Patrick Kelly, of the University of California at Berkeley, reported the discovery January 5 at a meeting of the American Astronomical Society.


Gravity from the cluster warps light from background galaxies and creates three images of Refsdal’s galactic home. One of those images lands on another galaxy within the cluster, whose gravity created the 2014 quadruple supernova display. Shortly after that quartet, several researchers predicted that Refsdal would show up once more in late 2015. Almost on schedule, the supernova appeared in a different image of the host galaxy closer to the center of the cluster.


For a supernova that keeps on giving, the December event might be its last, says Kelly, because there are no other paths for the light to take through the cluster. “It’s going to be sad when it finally fades away.”

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NuSTAR Finds Cosmic Clumpy Doughnut Around Black Hole

NuSTAR Finds Cosmic Clumpy Doughnut Around Black Hole | Amazing Science | Scoop.it

The most massive black holes in the universe are often encircled by thick, doughnut-shaped disks of gas and dust. This deep-space doughnut material ultimately feeds and nourishes the growing black holes tucked inside. Until recently, telescopes weren't able to penetrate some of these doughnuts, also known as tori.


"Originally, we thought that some black holes were hidden behind walls or screens of material that could not be seen through," said Andrea Marinucci of the Roma Tre University in Italy, lead author of a new Monthly Notices of the Royal Astronomical Society study describing results from NASA's Nuclear Spectroscopic Telescope Array, or NuSTAR, and the European Space Agency's XMM-Newton space observatory.


With its X-ray vision, NuSTAR recently peered inside one of the densest of these doughnuts known to surround a supermassive black hole. This black hole lies at the center of a well-studied spiral galaxy called NGC 1068, located 47 million light-years away in the Cetus constellation. The observations revealed a clumpy, cosmic doughnut. "The rotating material is not a simple, rounded doughnut as originally thought, but clumpy," said Marinucci.


Doughnut-shaped disks of gas and dust around supermassive black holes were first proposed in the mid-1980s to explain why some black holes are hidden behind gas and dust, while others are not. The idea is that the orientation of the doughnut relative to Earth affects the way we perceive a black hole and its intense radiation. If the doughnut is viewed edge-on, the black hole is blocked. If the doughnut is viewed face-on, the black hole and its surrounding, blazing materials can be detected. This idea is referred to as the unified model because it neatly joins together the different black hole types, based solely upon orientation.


In the past decade, astronomers have been finding hints that these doughnuts aren't as smoothly shaped as once thought. They are more like defective, lumpy doughnuts that a doughnut shop might throw away.


The new discovery is the first time this clumpiness has been observed in an ultra-thick doughnut, and supports the idea that this phenomenon may be common. The research is important for understanding the growth and evolution of massive black holes and their host galaxies. "We don't fully understand why some supermassive black holes are so heavily obscured, or why the surrounding material is clumpy," said co-author Poshak Gandhi of the University of Southampton in the United Kingdom. "This is a subject of hot research."

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Chandra finds remarkable ribbon of hot gas trailing behind a galaxy

Chandra finds remarkable ribbon of hot gas trailing behind a galaxy | Amazing Science | Scoop.it

An extraordinary ribbon of hot gas trailing behind a galaxy like a tail has been discovered using data from NASA's Chandra X-ray Observatory. This ribbon, or X-ray tail, is likely due to gas stripped from the galaxy as it moves through a vast cloud of hot intergalactic gas. With a length of at least 250,000 light years, it is likely the largest of such a tail ever detected.


The tail is located in the galaxy cluster Zwicky 8338, which is almost 700 million light years from Earth. The length of the tail is more than twice the diameter of the entire Milky Way galaxy. The tail contains gas at temperatures of about ten million degrees, about twenty million degrees cooler than the intergalactic gas, but still hot enough to glow brightly in X-rays that Chandra can detect.


The researchers think the tail was created as a galaxy known as CGCG254-021, or perhaps a group of galaxies dominated by this large galaxy, plowed through the hot gas in Zwicky 8338. The pressure exerted by this rapid motion caused gas to be stripped away from the galaxy.


Galaxy clusters are the largest structures in the Universe held together by gravity. They consist of hundreds, or even thousands, of galaxies, enormous pools of hot gas, and vast amounts of unseen dark matter. "Since galaxy clusters are so enormous, they play a critical role in understanding how our Universe evolves," said Gerrit Schellenberger of the University of Bonn in Germany, who led the study. "To understand galaxy clusters we need to understand how their galaxies change with time, and these X-ray tails provide an important element."


Images from Chandra and the NSF's Karl Jansky Very Large Array show that the galaxy CGCG254-021 appears to be moving towards the bottom of the image, with the tail following behind. There is a significant gap between the X-ray tail and the galaxy, the largest ever seen.

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Mystery bright spots could be first glimpse of another universe leaving its mark on ours

Mystery bright spots could be first glimpse of another universe leaving its mark on ours | Amazing Science | Scoop.it

The curtain at the edge of the universe may be rippling, hinting that there’s more backstage. Data from the European Space Agency’s Planck telescope could be giving us our first glimpse of another universe, with different physics, bumping up against our own.


That’s the tentative conclusion of an analysis by Ranga-Ram Chary, a researcher at Planck’s US data centre in California. Armed with Planck’s painstaking map of the cosmic microwave background (CMB) – light lingering from the hot, soupy state of the early universe – Chary revealed an eerie glow that could be due to matter from aneighbouring universe leaking into ours.


This sort of collision should be possible, according to modern cosmological theories that suggest the universe we see is just one bubble among many. Such a multiverse may be a consequence of cosmic inflation, the widely accepted idea that the early universe expanded exponentially in the slimmest fraction of a second after the big bang.


Once it starts, inflation never quite stops, so a multitude of universes becomes nearly inevitable. “I would say most versions of inflation in fact lead to eternal inflation, producing a number of pocket universes,” says Alan Guth of the Massachusetts Institute of Technology, an architect of the theory.


Energy hidden in empty space drives inflation, and the amount that’s around could vary from place to place, so some regions would eventually settle down and stop expanding at such a manic pace. But the spots where inflation is going gangbusters would spawn inflating universes. And even areas within these new bubbles could balloon into pocket universes themselves.


Like compositions on the same theme, each universe produced this way would be likely to have its own spin on physics. The matter in some bubbles – the boring ones – would fly apart within 10-40 seconds of their creation. Others would be full of particles and rules similar to ours, or even exactly like ours. In the multiverse of eternal inflation, everything that can happen has happened – and will probably happen again. That notion could explain why the physical constants of our universe seem to be so exquisitely tuned to allow for galaxies, stars, planets and life (see “Just right for life?“).


Sadly, if they do exist, other bubbles are nigh on impossible to learn about. With the space between them and us always expanding, light is too slow to carry any information between different regions. “They could never even know about each other’s existence,” says Matthew Johnson of York University in Toronto, Canada. “It sounds like a fun idea but it seems like there’s no way to test it.”


In 2007, Johnson and his PhD adviser proposed that these clashing bubbles might show up as circular bruises on the CMB. They were looking for cosmic dance partners that resembled our own universe, but with more of everything. That would make a collision appear as a bright, hot ring of photons.


By 2011, they were able to search for them in data from NASA’s WMAP probe, the precursor to Planck. But they came up empty-handed. Now Chary thinks he may have spotted a different signature of a clash with a foreign universe. “There are two approaches, looking for different classes of pocket universes,” Johnson says. “They’re hunting for lions, and we’re hunting for polar bears.” Instead of looking at the CMB itself, Chary subtracted a model of the CMB from Planck’s picture of the entire sky. Then he took away everything else, too: the stars, gas and dust.


With our universe scrubbed away, nothing should be left except noise. But in a certain frequency range, scattered patches on the sky look far brighter than they should. If they check out, these anomalous clumps could be caused by cosmic fist-bumps: our universe colliding with another part of the multiverse (arxiv.org/abs/1510.00126). These patches look like they come from the era a few hundred thousand years after the big bang when electrons and protons first joined forces to create hydrogen, which emits light in a limited range of colours. We can see signs of that era, called recombination, in the light from that early hydrogen. Studying the light from recombination could be a unique signature of the matter in our universe – and potentially distinguish signs from beyond. “This signal is one of the fingerprints of our own universe,” says Jens Chluba of the University of Cambridge. “Other universes should leave a different mark.”

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Astrophysicists produce the first age map of the halo of the Milky Way

Astrophysicists produce the first age map of the halo of the Milky Way | Amazing Science | Scoop.it

University of Notre Dame astronomer Timothy Beers and his Galactic Archaeology group, which includes Notre Dame astronomers Daniela Carollo and Vinicius Placco, have led an international team of researchers that produced the first chronographic (age) map of the halo of the Milky Way galaxy. The halo, along with the disk and bulge, are the primary components of the galaxy. Using a sample of 4,700 blue horizontal-branch (BHB) stars from the Sloan Digital Sky Survey, the research team showed that the oldest stars are concentrated in the central region of the galaxy, confirming predictions from numerical simulations of galaxy assembly. The researchers have also shown that chronographic maps such as theirs can also be used to identify complex structures of stars still in the process of being added to the halo system of our galaxy.


Daniela Carollo, left, Timothy Beers and Vinicius Placco

The researchers used the colors of BHB stars, which burn helium in their cores, to produce the age map. The technique relies on the fact that the colors of BHB stars are related to their masses, which in turn are related to their ages. The research results allowed the team, for the first time, to demonstrate two primary results.


“The oldest stars in the galaxy are concentrated toward the center of the galaxy, as predicted by previous numerical simulations of the assembly of our Milky Way,” Beers said. “Surprisingly, the region of the oldest stars extends all the way to the halo region close to the sun. This Ancient Chronographic Sphere can now be explored in order to study the properties of these old stars, which will tell us about the chemistry of the early universe.”


The researchers have also resolved the ages of dwarf galaxies and their stellar debris, which was stripped from them due to their gravitational interaction with the Milky Way. “This information can be used to tell us the assembly history of our galaxy,” Beers said. “We can now search for additional debris streams in the halo of the galaxy, based on their contrast in age, rather than simply their density contrast.”

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First biological signature of a supernova in magnetotactic bacteria

First biological signature of a supernova in magnetotactic bacteria | Amazing Science | Scoop.it

In fossil remnants of iron-loving bacteria, researchers of the Cluster of Excellence Origin and Structure of the Universe at the Technische Universitaet Muenchen (TUM), found a radioactive iron isotope that they trace back to a supernova in our cosmic neighborhood. This is the first proven biological signature of a starburst on our Earth. The age determination of the deep-drill core from the Pacific Ocean showed that the supernova must have occurred about 2.2 million years ago, roughly around the time when the modern human developed.


Most of the chemical elements have their origin in core collapse supernovae. When a star ends its life in a gigantic starburst, it throws most of its mass into space. The radioactive iron isotope Fe-60 is produced almost exclusively in such supernovae. Because its half-life of 2.62 million years is short compared to the age of our solar system, no supernova iron should be present on Earth. Therefore, any discovery of Fe-60 on Earth would indicate a supernova in our cosmic neighborhood. In the year 2004, Fe-60 was discovered on Earth for the first time in a ferromanganese crust obtained from the floor of the equatorial Pacific Ocean. Its geological dating puts the event around 2.2 million years ago.


So-called magnetotactic bacteria live within the sediments of Earth's oceans, close to the water-sediment interface. They make within their cells hundreds of tiny crystals of magnetite (Fe3O4), each approximately 80 nanometers in diameter. The magnetotactic bacteria obtain the iron from atmospheric dust that enters the ocean. Nuclear astrophysicist Shawn Bishop from the Technische Universitaet Muenchen conjectured, therefore, that Fe-60 should also reside within those magnetite crystals produced by magnetotactic bacteria extant at the time of the supernova interaction with our planet. These bacterially produced crystals, when found in sediments long after their host bacteria have died, are called "magnetofossils."


Shawn Bishop and his colleagues analyzed parts of a Pacific Ocean sediment core obtained from the Ocean Drilling Program, dating between about 1.7 million and 3.3 million years ago. They took sediment samples corresponding to intervals of about 100,000 years and treated them chemically to selectively dissolve the magnetofossils -- thereby extracting any Fe-60 they might contain.


Finally, using the ultra sensitive accelerator mass spectrometry system at the Maier Leibnitz Laboratory in Garching, Munich, they found a tantalizing hint of Iron-60 atoms occurring around 2.2 million years ago, which matches the expected time from the ferromanganese study. "It seems reasonable to suppose that the apparent signal of Fe-60 could be remains of magnetite chains formed by bacteria on the sea floor as a starburst showered on them from the atmosphere," Shawn Bishop says. He and his team are now preparing to analyze a second sediment drill core, containing upwards of 10 times the amount of material as the first drill core, to see if it also holds the Fe-60 signal and, if it does, to map out the shape of the signal as a function of time.

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Three new gravitational wave projects unveiled in China

Three new gravitational wave projects unveiled in China | Amazing Science | Scoop.it
Chinese scientists have unveiled three separate projects to investigate gravitational waves, state media said Wednesday, days after earthshaking US discoveries that confirmed Einstein's century-old predictions.


Space officials said such research would give China—which has an ambitious, military-run, multi-billion-dollar space programme that Beijing sees as symbolising the country's progress—an opportunity to become a "world leader" in the field.


Gravitational waves are direct evidence of ripples in the fabric of space-time, and their first-ever observation was announced by US scientists last week. The Chinese Academy of Sciences (CAS) rolled out a proposal for a space-based gravitational wave detection project, the official Xinhua news agency reported.


The proposed Taiji programme, named after the "supreme ultimate" of Chinese philosophy symbolised by the yin-yang sign, would send satellites of its own into orbit or share equipment with the European Space Agency's eLISA initiative.


Separately, Sun Yat-sen University in Guangzhou also proposed to launch satellites into space, while the Institute of High Energy Physics at CAS suggested a land-based scheme in Tibet. All three projects have yet to obtain government approval, state media said.

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Galaxy Clusters Reveal New Dark Matter Insights

Galaxy Clusters Reveal New Dark Matter Insights | Amazing Science | Scoop.it
Dark matter is a mysterious cosmic phenomenon that accounts for 27 percent of all matter and energy. Though dark matter is all around us, we cannot see it or feel it. But scientists can infer the presence of dark matter by looking at how normal matter behaves around it.

Galaxy clusters, which consist of thousands of galaxies, are important for exploring dark matter because they reside in a region where such matter is much denser than average. Scientists believe that the heavier a cluster is, the more dark matter it has in its environment. But new research suggests the connection is more complicated than that.

"Galaxy clusters are like the large cities of our universe. In the same way that you can look at the lights of a city at night from a plane and infer its size, these clusters give us a sense of the distribution of the dark matter that we can't see," said Hironao Miyatake at NASA's Jet Propulsion Laboratory, Pasadena, California.

A new study in Physical Review Letters, led by Miyatake, suggests that the internal structure of a galaxy cluster is linked to the dark matter environment surrounding it. This is the first time that a property besides the mass of a cluster has been shown to be associated with surrounding dark matter.

Researchers studied approximately 9,000 galaxy clusters from the Sloan Digital Sky Survey DR8 galaxy catalog, and divided them into two groups by their internal structures: one in which the individual galaxies within clusters were more spread out, and one in which they were closely packed together. The scientists used a technique called gravitational lensing -- looking at how the gravity of clusters bends light from other objects -- to confirm that both groups had similar masses.

But when the researchers compared the two groups, they found an important difference in the distribution of galaxy clusters. Normally, galaxy clusters are separated from other clusters by 100 million light-years on average. But for the group of clusters with closely packed galaxies, there were fewer neighboring clusters at this distance than for the sparser clusters. In other words, the surrounding dark-matter environment determines how packed a cluster is with galaxies.

"This difference is a result of the different dark-matter environments in which the groups of clusters formed. Our results indicate that the connection between a galaxy cluster and surrounding dark matter is not characterized solely by cluster mass, but also its formation history," Miyatake said.

Study co-author David Spergel, professor of astronomy at Princeton University in New Jersey, added, "Previous observational studies had shown that the cluster's mass is the most important factor in determining its global properties. Our work has shown that 'age matters': Younger clusters live in different large-scale dark-matter environments than older clusters."

The results are in line with predictions from the leading theory about the origins of our universe. After an event called cosmic inflation, a period of less than a trillionth of a second after the big bang, there were small changes in the energy of space called quantum fluctuations. These changes then triggered a non-uniform distribution of matter. Scientists say the galaxy clusters we see today have resulted from fluctuations in the density of matter in the early universe.

"The connection between the internal structure of galaxy clusters and the distribution of surrounding dark matter is a consequence of the nature of the initial density fluctuations established before the universe was even one second old," Miyatake said.

Researchers will continue to explore these connections.

"Galaxy clusters are remarkable windows into the mysteries of the universe. By studying them, we can learn more about the evolution of large-scale structure of the universe, and its early history, as well as dark matter and dark energy," Miyatake said.
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Discovery Of Most Powerful Supernova To Date, 570 Billion Times The Luminosity Of The Sun

Discovery Of Most Powerful Supernova To Date, 570 Billion Times The Luminosity Of The Sun | Amazing Science | Scoop.it

An international team of researchers has observed a supernova explosion which is twice as powerful as the previous record holder.


During the supernova explosion, luminosity of the star reached 570 billion times the luminosity of the sun, and is approximately 20 times brighter than the Milky Way combined. The article was published in the journal Science. The supernova was discovered in Chile by the All Sky Automated Survey for SuperNovae (ASASSN).


The team was led by Dong Subo, Thousand Youth Talent Plan research professor at The Kavli Institute for Astronomy and Astrophysics at Peking University and member of ASASSN. The star, named ASASSN-15lh, is a rare breed—it is classified as a “super-luminous supernova,” and at 3.8 billion light years away from the Earth, it is among the closest supernovae ever observed.


“ASASSN-15lh is the most powerful supernova discovered in human history,” said Dong. “The explosion’s mechanism and power source remain shrouded in mystery because all known theories meet serious challenges in explaining the immense amount of energy ASASSN-15lh has radiated.”


The first spectral line of the ASASSN-15lh was observed by B. J. Shappee of Carnegie Observatories in Chile. Astronomers generally use spectral lines to analyze projectiles from supernova explosions to determine their chemical components and physical conditions.


This analysis in turn helps astronomers classify supernovae and understand the physical process of their explosions. However, the spectral lines of ASASSN-15lh was significantly different from all the other supernovae discovered by ASASSN.


Initially, this perplexed many astronomers. It was only while discussing the issue with Assistant Professor Jose Prieto from Universidad Diego Portales and Professor K. Z. Stanek from Ohio State University that Dong realized that ASASSN-15lh could be a superluminous supernova.


According to his estimations, if ASASSN-15lh was indeed 3.8 billion light years away from us, then its most significant spectral characteristics should be very similar to the spectrum of a superluminous supernova discovered in 2010.

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Illustris Simulation: Most detailed simulation of our Universe ever produced

The Illustris simulation is the most ambitious computer simulation of our Universe yet performed. The calculation tracks the expansion of the universe, the gravitational pull of matter onto itself, the motion of cosmic gas, as well as the formation of stars and black holes. These physical components and processes are all modeled starting from initial conditions resembling the very young universe 300,000 years after the Big Bang and until the present day, spanning over 13.8 billion years of cosmic evolution. The simulated volume contains tens of thousands of galaxies captured in high-detail, covering a wide range of masses, rates of star formation, shapes, sizes, and with properties that agree well with the galaxy population observed in the real universe. The simulations were run on supercomputers in France, Germany, and the US. The largest was run on 8,192 compute cores, and took 19 million CPU hours. A single state-of-the-art desktop computer would require more than 2000 years to perform this calculation.

Find out more at: 
http://www.illustris-project.org

Publication: 
"Properties of galaxies reproduced by a hydrodynamic simulation", Vogelsberger, Genel, Springel, Torrey, Sijacki, Xu, Snyder, Bird, Nelson, Hernquist, Nature 509, 177-182 (08 May 2014) doi:10.1038/nature13316

Music: 
moonbooter (http://www.moonbooter.de/)

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Milky Way growth chart reveals how galaxy evolved

Milky Way growth chart reveals how galaxy evolved | Amazing Science | Scoop.it

Scientists have made a cosmic growth chart of the Milky Way, an innovative blending of data collected by the ongoing Sloan Digital Sky Survey and a new technique to determine the ages of stars. The analysis shows the galaxy's central disc formed from the inside out, with red giant stars as old as about 13 billion years clustered toward the centre and younger stars about 1 billion years old closer to the disc's edge.


"What we're able to do ... is understand how our galaxy has formed in detail, looking at the dispersion of ages, the gradient of the ages, how the ages change as a function of both the height from the disc's plane and the radius," astronomer Dr Melissa Ness told reporters at the American Astronomical Society meeting in Kissimmee, Florida.


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Before There Were Stars: The Unlikely Heroes That Made Starlight Possible

Before There Were Stars: The Unlikely Heroes That Made Starlight Possible | Amazing Science | Scoop.it

The universe is the grandest merger story that there is. Complete with mysterious origins, forces of light and darkness, and chemistry complex enough to make the chemical conglomerate BASF blush, the trip from the first moments after the Big Bang to the formation of the first stars is a story of coming together at length scales spanning many orders of magnitude. To piece together this story, scientists have turned to the skies, but also to the laboratory to simulate some of the most extreme environments in the history our universe. The resulting narrative is full of surprises. Not least among these, is how nearly it didn’t happen—and wouldn’t have, without the roles played by some unlikely heroes. Two of the most important, at least when it comes to the formation of stars, which produced the heavier elements necessary for life to emerge, are a bit surprising: dark matter and molecular hydrogen. Details aside, here is their story.


Dark Matter - Molecular Hydrogen - Stars

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Kepler Telescope Spotted Something Very Strange Surrounding A Distant Star

Kepler Telescope Spotted Something Very Strange Surrounding A Distant Star | Amazing Science | Scoop.it

Since its first light in 2009, the Kepler Space Telescope has been scanning the cosmos in search of habitable worlds beyond our Solar System. During its routine observations, the telescope observed something very unusual. Nestled between the constellations Cygnus and Lyra, sits a strange and intriguing star.


Kepler is designed to observe stars and look for tiny dips in their brightness. These dips, especially if they repeat, can be a sign the star has one or more planets orbiting it. By measuring the timing and the size of the dips, scientists can learn a great deal about the transiting planet. The data is then processed automatically by computers with algorithms designed to look for repeating patterns – a sign that something is orbiting the star.


Kepler focused on this one region for four years, observing as many as 150,000 stars simultaneously. Due to the massive amounts of data collected, Kepler scientists rely on “citizen scientists” through a website called Planet Hunters to help them scour the data for anything unusual. In 2011, one star in particular was flagged as unusual.


Kepler observed the star KIC 8462852 for four years starting in 2009. Typically, orbiting planets only dim the light of their host star for a period of a few hours to a few days depending on their orbit. A group of citizen scientists noticed that this star appeared to have two small dips in 2009, followed by a large dip lasting almost a week in 2011, and finally a series of multiple dips significantly dimming the star’s light in 2013.


Tabetha Boyajian, a postdoc at Yale, told The Atlantic: “We’d never seen anything like this star. It was really weird. We thought it might be bad data or movement on the spacecraft, but everything checked out.”


The pattern of dips indicates that the star is orbited by a large, irregular-shaped mass. If it were orbiting a young star, this mass might be a protoplanetary disc, but KIC 8462852 is not a young star. We would also expect to see the presence of dust emitting infrared light, which hasn’t been observed. So what is this orbiting mass? Scientists predict that whatever it is, it had to have formed recently as it would have been pulled in by the star’s gravity and consumed.


Boyajian recently published a paper offering several possible explanations for the bizarre transits. The leading theory is that a family of exocomets passed too close to the star, and were shredded into pieces by the star’s massive gravity. The remaining dust and debris could be left to orbit the star. But researchers from UC Berkeley’s SETI Institute think it could be something else entirely: They think this could be a sign of alien technology. Boyajian is working with SETI and Jason Wright, an astronomer from Penn State University, to develop a proposal to observe the star with NRAO’s Green Bank Telescope to search for radio waves. If they detect anything intriguing, they then have plans to use the Very Large Array (VLA) in New Mexico to listen for what could be the sounds of alien technology.  


The first observations are estimated to take place in January, with a potential follow-up planned for next fall. Of course, if they stumble upon something incredible, the researchers could expect to follow-up with the VLA straight away. Kepler also plans to observe KIC 8462852 in May 2017, when the mass is expected to transit the star again.


Via Guillaume Decugis
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Guillaume Decugis's curator insight, October 14, 2015 11:28 PM
Could be debris of comets or... signs of an alien technology. Seriously.
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Black holes could grow as large as 50 billion suns before their food crumbles into stars

Black holes could grow as large as 50 billion suns before their food crumbles into stars | Amazing Science | Scoop.it

Black holes at the heart of galaxies could swell to 50 billion times the mass of the sun before losing the discs of gas they rely on to sustain themselves, according to research at the University of Leicester.


In a study titled ‘How Big Can a Black Hole Grow?’ published in the journal Monthly Notices Letters of the Royal Astronomical Society, Professor Andrew King from the University of Leicester’s Department of Physics and Astronomy explores supermassive black holes at the centre of galaxies, around which are regions of space where gas settles into an orbiting disc.


This gas can lose energy and fall inwards, feeding the black hole. But these discs are known to be unstable and prone to crumbling into stars. Professor King calculated how big a black hole would have to be for its outer edge to keep a disc from forming, coming up with the figure of 50 billion solar masses.


The study suggests that without a disc, the black hole would stop growing, meaning 50 billion suns would roughly be the upper limit. The only way it could get larger is if a star happened to fall straight in or another black hole merged with it.


Professor King said: “The significance of this discovery is that astronomers have found black holes of almost the maximum mass, by observing the huge amount of radiation given off by the gas disc as it falls in. The mass limit means that this procedure should not turn up any masses much bigger than those we know, because there would not be a luminous disc.


“Bigger black hole masses are in principle possible - for example, a hole near the maximum mass could merge with another black hole, and the result would be bigger still. But no light would be produced in this merger, and the bigger merged black hole could not have a disc of gas that would make light.

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JESUS MORENO LOPEZ's curator insight, January 4, 1:46 PM

añada su visión ...

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Physicists continue to investigate why the universe did not collapse shortly after big bang

Physicists continue to investigate why the universe did not collapse shortly after big bang | Amazing Science | Scoop.it

According to the best current physics models, the universe should have collapsed shortly after inflation—the period that lasted for a fraction of a second immediately after the Big Bang.


The problem lies in part with Higgs bosons, which were produced during inflation and which explain why other particles have the masses that they do. Previous research has shown that, in the early universe, the Higgs field may have acquired large enough fluctuations to overcome an energy barrier that caused the universe to transition from its standard vacuum state to a negative energy vacuum state, which would have caused the universe to quickly collapse in on itself.


In a new paper published in Physical Review Letters, Matti Herranen at the University of Copenhagen and coauthors may have come a step closer to solving the problem by constraining the strength of the coupling between the Higgs field and gravity, which is the last unknown parameter of the standard model.


As the physicists explain, the stronger the Higgs field is coupled to gravity, the larger are the fluctuations that may eventually trigger a fatal transition to the negative energy vacuum state.


In the new paper, the scientists calculated that a collapse after inflation would have happened only if the coupling strength had been above a value of 1. Combining this result with the lower bound of 0.1, which the same physicists derived last year by analyzing the requirements for stability during (rather than after) inflation, and the range of 0.1-1 constrains the coupling to near its historically estimated value of 1/6.


This value of 1/6 is traditionally used as an estimate because it corresponds to zero Higgs-gravity coupling, though it is likely incorrect. Narrowing down the Higgs-gravity coupling strength will guide physicists when analyzing experimental data to help pinpoint the coupling value with greater precision. Data on the cosmic microwave background radiation and gravitational waves, for example, are expected to help further constrain the value. When combined with other parameters, the Higgs-gravity coupling strength should produce a picture of a universe that did not transition to a state of collapse.

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The jet of a black hole drives multiple winds in a nearby galaxy

The jet of a black hole drives multiple winds in a nearby galaxy | Amazing Science | Scoop.it

A team of astrophysicists led by Dr Kalliopi Dasyra discovered fast winds of molecular and atomic gas that were caused by the interaction of the jet of a supermassive black hole with interstellar medium clouds in the nearby galaxy IC5063. The winds are detected in four discrete regions near the jet, at distances as large as ~3000 light years away from the black hole. This discovery indicates that black hole jets can influence the evolution of galaxies by increasing the turbulence of the gas and suppressing the formation of new stars at large scales.


Supermassive black holes of hundreds of millions of solar masses commonly reside in galactic centers. These black holes can gravitationally attract interstellar matter from within dozens of light years away. As matter inflows toward a black hole, it becomes heated and ionized. Its accretion occurs through a disk because of rotation. Collimated streams of plasma, called jets, emerge from the accretion disk as a result of magnetic fields.


Jets can be very energetic—they can transport energy at a rate that is 10 orders of magnitude greater than that radiated by the sun. By injecting energy into the interstellar medium, jets can expel gas from galaxies, increase gas turbulence, and prevent the gas collapse that leads to star formation. Models have indicated that this process can take place at the scale of entire galaxies because bow shocks sweep the interstellar gas as jets propagate through it. In this manner, jets can affect galaxy evolution.


Most direct evidence that the jet of a black hole accelerates interstellar gas comes from observations of the galaxy IC5063, 160 million light years away from us. This galaxy has a rare characteristic: The jet is nearly aligned with the dense gas disk, depositing energy into it. In most other cases, the energy is expelled perpendicularly to the disk, keeping most of the dense gas intact.


The astrophysicists analysed near-infrared data of IC5063 from the Very Large Telescope of the European Southern Observatory, and discovered winds starting from four discrete regions near the jet. The winds are caused by the impact of the jet upon dense clouds, or by the passage of the bow shocks by dense clouds. They carry molecular hydrogen and iron ions with high line-of-sight velocities of 600 to 1200 km/s with respect to the regular gas motions. Higher temperatures are observed for the gas in the wind than in its surroundings. The increase in the gas turbulence and temperature can affect star formation in an impressively large area, corresponding to ~1/5th of the molecular gas disk.


More details on this work can be found in an Astrophysical Journal paper titled "A radio jet drives a molecular and atomic gas outflow in multiple regions within one square kiloparsec of the nucleus of the nearby galaxy IC5063". The paper, with a publication date of December 04 2015, can be downloaded from the journal's website (available from Friday, December 4) (http://iopscience.iop.org/article/10.1088/0004-637X/815/1/34) or from the arXiv pre-print server (http://arxiv.org/abs/1503.05484).

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Dark matter might cause fundamental constants to change over time

Dark matter might cause fundamental constants to change over time | Amazing Science | Scoop.it

The fundamental constants of nature—such as the speed of light, Planck's constant, and Newton's gravitational constant—are thought to be constant in time, as their name suggests. But scientists have questioned this assumption as far back as 1937, when Paul Dirac hypothesized that Newton's gravitational constant might decrease over time.


Now in a new paper published in Physical Review Letters, Yevgeny V. Stadnik and Victor V. Flambaum at the University of New South Wales in Sydney, Australia, have theoretically shown that dark matter can cause the fundamental constants of nature to slowly evolve as well as oscillate due to oscillations in the dark matter field. This idea requires that the weakly interacting dark matter particles be able to interact a small amount with standard model particles, which the scientists show is possible.


In their paper, the scientists considered a model in which dark matter is made of weakly interacting, low-mass particles. In the early Universe, according to the model, large numbers of such dark matter particles formed an oscillating field. Because these particles interact so weakly with standard model particles, they could have survived for billions of years and still exist today, forming what we know as dark matter.


Although these low-mass dark matter particles are weakly interacting, they are thought to still interact with standard model particles to some extent, but it's unclear exactly how much. By using data from experiments that have measured the amount of helium produced during big bang nucleosynthesis, as well as measurements of the rare element dysprosium and the cosmic microwave background, Stadnik and Flambaum have derived the most stringent limits to date on how strongly such dark matter particles interact with photons, electrons, and light quarks, improving on existing constraints by up to 15 orders of magnitude.


The new limits on the dark matter interaction strength allow for the possibility that an oscillating, low-mass dark matter field coupled to standard model particles causes variations in the fundamental constants. As the scientists explain, this could have important implications for understanding life's origins.


The fundamental constants are 'fine-tuned' to be consistent with the existence of life in the Universe. If the physical constants were even slightly different, life could not have appeared. The discovery of varying fundamental 'constants' may help shed important light on how the physical constants came to have their life-sustaining values today. We simply appeared in an area of the Universe where they are consistent with our existence. Whether or not the fundamental constants actually do vary due to dark matter is still an open question, but the scientists hope that future experiments with atomic clocks, laser interferometers, and other devices may help test out the new idea.

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malik matwi's comment, December 13, 2015 2:58 PM
neither dark matter nor energy http://iiste.org/Journals/index.php/APTA/article/view/26837