Tag: dense (page 2 of 6)

Far Flung Star Cluster Found at Milky Way’s Edge

Astronomers in Brazil have discovered a cluster of stars forming at the edge of the Milky Way, according to a press release from the Royal Astronomical Society.




Excerpt from  news.discovery.com


This is unusual because it was believed that stars generally take form closer to the center of our spiral-shaped galaxy, rather than from its swirling, spiral arms, which are thousands of light-years away. These two clusters of stars — named Camargo 438 and 439 — were seen in a cloud at the galaxy’s outskirts.

Denilso Camargo, an astronomer at the Federal University of Rio Grande do Sul in Porto Alegre, Brazil, led a team that analyzed data from NASA’s orbiting Wide-Field Infrared Survey Explorer (WISE) observatory. They zeroed in on dense clumps of gas in so-called giant molecular clouds(GMCs) that are known to generate stars. GMCs are mainly located in the inner part of the galactic disc.

The new star clusters lie about 16,000 light-years away from the main disk of the Milky Way galaxy. How did they form there? The scientists aren’t yet sure but Camargo theorizes that one of two scenarios could have led to the stars’ formation.

In the first scenario, called the “chimney model,” supernovas could have flung the gas and dust that formed the cloud out of the Milky Way. Another explanation is the material could have drifted in from outside the galaxy.


“Our work shows that the space around the Galaxy is a lot less empty that we thought,” said Camargo. “The new clusters of stars are truly exotic.”

Camargo’s team published their results in the journal Monthly

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Archaeologists find two lost cities deep in Honduras jungle


Archaeologists in Honduras have found dozens of artifacts at a site where they believe twin cities stood. Photograph: Dave Yoder/National Geographic
Archaeologists in Honduras have found dozens of artifacts at a site where they believe twin cities stood. Photograph: Dave Yoder/National Geographic
Excerpt from theguardian.com


Archaeological team say they have set foot in a place untouched by humans for at least 600 years in a site that may be the ‘lost city of the monkey god’

Archaeologists have discovered two lost cities in the deep jungle of Honduras, emerging from the forest with evidence of a pyramid, plazas and artifacts that include the effigy of a half-human, half-jaguar spirit.
The team of specialists in archaeology and other fields, escorted by three British bushwhacking guides and a detail of Honduran special forces, explored on foot a remote valley of La Mosquitia where an aerial survey had found signs of ruins in 2012.
Chris Fisher, the lead US archaeologist on the team, told the Guardian that the expedition – co-coordinated by the film-makers Bill Benenson and Steve Elkins, Honduras and National Geographic (which first reported the story on its site) – had by all appearances set foot in a place that had gone untouched by humans for at least 600 years.
“Even the animals acted as if they’ve never seen people,” Fisher said. “Spider monkeys are all over place, and they’d follow us around and throw food at us and hoot and holler and do their thing.”
“To be treated not as a predator but as another primate in their space was for me the most amazing thing about this whole trip,” he said.
Fisher and the team arrived by helicopter to “groundtruth” the data revealed by surveying technology called Lidar, which projects a grid of infrared beams powerful enough to break through the dense forest canopy.
The dense jungle of Honduras. Photograph: Dave Yoder/National Geographic
The dense jungle of Honduras.Photograph: Dave Yoder/National Geographic
That data showed a human-created landscape, Fisher said of sister cities not only with houses, plazas and structures, but also features “much like an English garden, with orchards and house gardens, fields of crops, and roads and paths.”
In the rainforest valley, they said they found stone structural foundations of two cities that mirrored people’s thinking of the Maya region, though these were not Mayan people. The area dates between 1000AD and 1400AD, and while very little is known without excavation of the site and surrounding region, Fisher said it was likely that European diseases had at least in part contributed to the culture’s disappearance.
The expedition also found and documented 52 artifacts that Virgilio Paredes, head of Honduras’s national anthropology and history institute, said indicated a civilisation distinct from the Mayans. Those artifacts included a bowl with an intricate carvings and semi-buried stone sculptures, including several that merged human and animal characteristics.
The cache of artifacts – “very beautiful, very fantastic,” in Fisher’s words – may have been a burial offering, he said, noting the effigies of spirit animals such as vultures and serpents.
Fisher said that while an archaeologist would likely not call these cities evidence of a lost civilisation, he would call it evidence of a culture or society. “Is it lost? Well, we don’t know anything about it,” he said.
The exploratory team did not have a permit to excavate and hopes to do so on a future expedition. “That’s the problem with archaeology is it takes a long time to get things done, another decade if we work intensively there, but then we’ll know a little more,” Fisher said.
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“This wasn’t like some crazy colonial expedition of the last century,” he added.
Despite the abundance of monkeys, far too little is known of the site still to tie it to the “lost city of the monkey god” that one such expedition claimed to have discovered. In about 1940, the eccentric journalist Theodore Morde set off into the Honduran jungle in search of the legendary “white city” that Spanish conquistadors had heard tales of in the centuries before.
He broke out of the brush months later with hundreds of artifacts and extravagant stories of how ancient people worshipped their simian deity. According to Douglas Preston, the writer National Geographic sent along with its own expedition: “He refused to divulge the location out of fear, he said, that the site would be looted. He later committed suicide and his site – if it existed at all – was never identified.”
Fisher emphasised that archaeologists know extraordinarily little about the region’s ancient societies relative to the Maya civilisation, and that it would take more research and excavation. He said that although some academics might find it distasteful, expeditions financed through private means – in this case the film-makers Benenson and Elkins – would become increasingly commonplace as funding from universities and grants lessened.
Fisher also suggested that the Lidar infrared technology used to find the site would soon be as commonplace as radiocarbon dating: “People just have to get through this ‘gee-whiz’ phase and start thinking about what we can do with it.”
Paredes and Fisher also said that the pristine, densely-wooded site was dangerously close to land being deforested for beef farms that sell to fast-food chains. Global demand has driven Honduras’s beef industry, Fisher said, something that he found worrying.
“I keep thinking of those monkeys looking at me not having seen people before. To lose all this over a burger, it’s a really hard pill to swallow.”

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What Big Bang? Universe May Have Had No Beginning at All

Excerpt from spacedaily.com What we don't know about the Universe... could fill the Universe. Two theoretical physicists have suggested nothing like the Big Bang played a role in the start of our universe 13.8 billion years ago, refuting Edwin Hubb...

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“Seedling” For Supermassive Black Holes Found




Excerpt from clapway.com

By William Large 

A recently discovered black hole may help astronomers to piece together the family tree of these enigmatic cosmic objects. While most black holes are classified as either stellar-mass or the supermassive black holes that can be found at the center of some galaxies, this new find fits into neither category.

The discovery, called the intermediate-mass black hole (IMBH), has proved to be a tricky proposition. With a mass somewhere between a few hundred to a few hundred thousand times that of our own Sun, the size of these intermediates can vary widely.

This particular black hole was found in an arm of the spiral galaxy NGC-2276, and has been sensibly named NGC-2276-3c. Lying about 100 million light-years from earth, astronomers were able to tease images through the use of NASA’s Chandra X-Ray Observatory and the European Very Long Baseline Interferometry Network.

Although researchers have theorized about the existence of these IMBHs, locating one has proven elusive until now. A recent to-be-published paper by an international team of researchers delves into the specifics of NGC-2276-3c.

“Astronomers have been looking very hard for these medium-sized black holes,” study co-author Tim Roberts, of the University of Durham in the United Kingdom, said in a statement. “There have been hints that they exist, but the IMBHs have been acting like a long-lost relative that isn’t interested in being found.”

So what was found? It appears that the recently discovery has characteristics of both the smaller stellar-mass and the much larger supermassive black holes. It serves as an intermediary between the two, and some think that these intermediaries are the beginnings of what could very well become a supermassive.

The team of researchers also noted that the black holes is firing off super powerful blasts of radio jets. Think of these as material, traveling at nearly the speed of light and emitting radio waves, which are thrown out of dense objects. Our newly found black hole is shooting them out almost 2000 light-years into space. Within a radius of approximately 1000 light-years around NGC-2276-3c there are no new star formations, suggesting that the radio jets are pushing out all the gas necessary for star creation.

The full report on NGC-2276-3c should be appearing shortly in the journal Monthly Notices of the Royal Astronomical Society.

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Rare doomed planet with extreme seasons discovered


Kepler432b.jpg
Illustration provided by the University of Heidelberg of the orbit of Kepler-432b (inner, red) in comparison to the orbit of Mercury around the Sun (outer, orange). The red dot in the middle indicates the position of the star around which the planet is orbiting. The size of the star is shown to scale, while the size of the planet has been magnified ten times for illustration purposes. (Graphic: Dr. Sabine Reffert)


Excerpt from foxnews.com/science


A rare planet has been discovered, and it doesn’t seem like a stop anyone would want to make on an intergalactic cruise. Found by two research teams independently of each other, Kepler-432b is extreme in its mass, density, and weather. Roughly the same size of Jupiter, the planet is also doomed- in 200 million years it will be consumed by its sun. “Kepler-432b is definitively a rarity among exoplanets around giant stars: it is a close-in gas-giant planet orbiting a star whose radius is 'quickly' increasing,” Davide Gandolfi, from the Landessternwarte Koenigstuhl (part of the Centre for Astronomy of the University of Heidelberg), told FoxNews.com. “The orbit of the planet has a radius of about 45 million kilometers [28 million miles] (as a reference point, the Earth-Sun distance is about 150 million kilometers [93.2 Million miles]), while most of the planets known to orbit giant stars have wider orbits. The stellar radius is already 3 million kilometers [almost 2 million miles] (i.e., about 4 times the Sun radius) and in less than 200 million years it will be large enough for the star to swallow up its planet.”

Gandolfi, a member of one of the research groups who discovered the rare planet, explains that much like Jupiter, Kepler-432b is a gas-giant celestial body composed mostly of hydrogen and helium, and is most likely to have a dense core that accounts for 6 percent or less of the planet’s mass. “The planet has a mass six times that of Jupiter, but is about the same size!” he says. “This means that it is not one of the largest planets yet discovered: it is one of the most massive!” The planet’s orbit brings it extremely close to its host star on some occasions, and very far away at others, which creates extreme seasonal changes. In its year - which lasts 52 Earth days - winters can get a little chilly and summers a bit balmy, to say the least. According to Gandolfi, “The highly eccentric orbit brings Kepler-432b at ‘only’ 24 million kilometers [15 million miles] from its host star, before taking it to about three times as far away. This creates large temperature excursions over the course of the planet year, which is of only 52 Earth days. During the winter season, the temperature on Kepler-432b drops down to 500 degrees Celsius [932 degrees Fahrenheit], whereas in summer it can goes up to nearly 1000 degrees Celsius [1832 degrees Fahrenheit].”

Then again, if you are crazy enough to visit Kepler-432b, you’d better do it fast. As stated before, its host star is set to swallow the planet whole in 200 million years, making the celestial body a rare find. “The paucity of close-in planets around giant stars is likely to be due to the fact that these planets have been already swallowed up by their host stars,” Gandolfi says. “Kepler-432b has been discovered ‘just in time before dinner!” The host star, which is red and possesses 1.35 times the mass of our sun, has partly exhausted the nuclear fuel in its core, and is slowly expanding, eventually growing large enough to swallow Kepler-432b. According to Gandolfi, this is a natural progression for all stars. “Stars first generate nuclear energy in their core via the fusion of Hydrogen into Helium,” he explained. “At this stage, their radii basically do not change much. This is because the outward thermal pressure produced by the nuclear fusion in the core is balanced by the inward pressure of gravitational collapse from the overlying layers. In other words, the nuclear power is the star pillar! Our Sun is currently ‘burning’ hydrogen in its core (please note that I used quotes: ‘burning’ does not mean a chemical reaction- we are talking about nuclear fusion reaction). However, this equilibrium between the two pressures does not last forever. Helium is heavier than hydrogen and tends to sink. The stellar core of the Kepler-432b's host star is currently depleted of hydrogen and it is mainly made of inert helium. The star generates thermal energy in a shell around the core through the nuclear fusion of hydrogen into helium. As a result of this, the star expands and cools down. This is why we call it ‘red giant’- the reddish color comes from the fact that the external layers of the atmosphere of the star are cooling down because they expand.”

Both research teams (the other was from the Max Planck Institute for Astronomy in Heidelberg) used Calar Alto Observatory’s 7.2- foot telescope in Andalucia, Spain. The planet was also studied by Landessternwarte Koenigstuhl researchers using the 8.5-foot Nordic Optical Telescope on La Palma, which is located in Spain’s Canary Islands.

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ALMA uncovers stellar nurseries in the Sculptor Galaxy, 11.5 million light years from home



ALMA uncovers stellar nurseries in the Sculptor Galaxy, 11.5 million light years from home
The Sculptor Galaxy


Excerpt from sciencerecorder.com

Starburst galaxies are named for their ability to convert gasses rapidly into new stars, at an accelerated speed that can sometimes be 1,000 times more rapid than your average spiral galaxy, such as the Milky Way. Why the disparity? In order to further investigate the reason that some galaxies seem to “burst” into being, whereas others take the better part of a few billion years, an international team of astronomers analyzed a cluster of star-forming gas clouds in the heart of NGC 253 – the Sculptor Galaxy, with the aid of the Atacama Large Millimeter/submillimeter Array (ALMA). The Sculptor Galaxy is among starburst galaxies closest to the Milky Way.

“All stars form in dense clouds of dust and gas,” said Adam Leroy, in an interview with Astronomy magazine. Leroy is an astronomer at Ohio State University in Columbus. “Until now, however, scientists struggled to see exactly what was going on inside starburst galaxies that distinguished them from other star-forming regions.”

Therefore, Leroy and his colleagues turn to the ALMA which is capable of examining star changing structures even in systems as distant as Sculptor. Already, they have successfully charted distribution and movement of various molecules within several clouds located at the Sculptor Galaxy’s core.


Because NGC 253, which is disk-shaped, is in the stages of a very intense starburst and located approximately 11.5 million light-years from home, it is the perfect target for study. ALMA picks it up with remarkable precision and resolution, so much so that the team was able to isolate and identify ten different stellar ‘nurseries,’ in which stars were in the process of forming. To appreciate the magnitude of this feat, it would have been impossible with previous telescopes, which blurred the regions together into one glow. 

“There is a class of galaxies and parts of galaxies, we call them starbursts, where we know that gas is just plain better at forming stars,” said Leroy. “To understand why, we took one of the nearest such regions and pulled it apart — layer by layer — to see what makes the gas in these places so much more efficient at star formation.”


More importantly, they recognized the distribution of several 40 millimeter-wavelength “signatures,” that given off by various molecules at the center of Sculptor Galaxy, signaling that a number of conditions were responsible for the development of these stars. This accounts for the diversity of the states of different stars corresponding to where they are found in star-forming clouds. One important compound, all too familiar and unwelcome on Earth, carbon monoxide (CO), correlates with massive envelopes of gases that are less dense within the stellar nurseries. Others, such as hydrogen cyanide (HCN), were present in the more dense reaches of active star formation. The rarer the molecules, for example, H13CN and H13CO+, suggest regions that are even denser.


Indeed, when the data was compared, researchers found that the gas clouds of the Sculptor Galaxy were ten times denser than those found in spiral galaxies, suggesting that because the clouds are so tightly packed, they can form star clusters much more rapidly than the Milky Way. At the same time, they give us further insight as to how stars are born, showing us the physical changes along the way, allowing astronomers a working model to compare with our own galaxy. 


“These differences have wide-ranging implications for how galaxies grow and evolve,” concluded Leroy. “What we would ultimately like to know is whether a starburst like Sculptor produces not just more stars, but different types of stars than a galaxy like the Milky Way. ALMA is bringing us much closer to that goal.”

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Every Black Hole Contains a New Universe


At the center of spiral galaxy M81 is a supermassive black hole about 70 million times more massive than our sun.



Excerpt from insidescience.org
A physicist presents a solution to present-day cosmic mysteries.



By: 
Nikodem Poplawski, Inside Science Minds Guest Columnist



(ISM) -- Our universe may exist inside a black hole. This may sound strange, but it could actually be the best explanation of how the universe began, and what we observe today. It's a theory that has been explored over the past few decades by a small group of physicists including myself. 
Successful as it is, there are notable unsolved questions with the standard big bang theory, which suggests that the universe began as a seemingly impossible "singularity," an infinitely small point containing an infinitely high concentration of matter, expanding in size to what we observe today. The theory of inflation, a super-fast expansion of space proposed in recent decades, fills in many important details, such as why slight lumps in the concentration of matter in the early universe coalesced into large celestial bodies such as galaxies and clusters of galaxies.
But these theories leave major questions unresolved. For example: What started the big bang? What caused inflation to end? What is the source of the mysterious dark energy that is apparently causing the universe to speed up its expansion?
The idea that our universe is entirely contained within a black hole provides answers to these problems and many more. It eliminates the notion of physically impossible singularities in our universe. And it draws upon two central theories in physics.
Nikodem Poplawski displays a "tornado in a tube." The top bottle symbolizes a black hole, the connected necks represent a wormhole and the lower bottle symbolizes the growing universe on the just-formed other side of the wormhole. Credit: Indiana University
In this picture, spins in particles interact with spacetime and endow it with a property called "torsion." To understand torsion, imagine spacetime not as a two-dimensional canvas, but as a flexible, one-dimensional rod. Bending the rod corresponds to curving spacetime, and twisting the rod corresponds to spacetime torsion. If a rod is thin, you can bend it, but it's hard to see if it's twisted or not.

The first is general relativity, the modern theory of gravity. It describes the universe at the largest scales. Any event in the universe occurs as a point in space and time, or spacetime. A massive object such as the Sun distorts or "curves" spacetime, like a bowling ball sitting on a canvas. The Sun's gravitational dent alters the motion of Earth and the other planets orbiting it. The sun's pull of the planets appears to us as the force of gravity.

The second is quantum mechanics, which describes the universe at the smallest scales, such as the level of the atom. However, quantum mechanics and general relativity are currently separate theories; physicists have been striving to combine the two successfully into a single theory of "quantum gravity" to adequately describe important phenomena, including the behavior of subatomic particles in black holes.
A 1960s adaptation of general relativity, called the Einstein-Cartan-Sciama-Kibble theory of gravity, takes into account effects from quantum mechanics. It not only provides a step towards quantum gravity but also leads to an alternative picture of the universe. This variation of general relativity incorporates an important quantum property known as spin. Particles such as atoms and electrons possess spin, or the internal angular momentum that is analogous to a skater spinning on ice.

Spacetime torsion would only be significant, let alone noticeable, in the early universe or in black holes. In these extreme environments, spacetime torsion would manifest itself as a repulsive force that counters the attractive gravitational force coming from spacetime curvature. As in the standard version of general relativity, very massive stars end up collapsing into black holes: regions of space from which nothing, not even light, can escape.
Here is how torsion would play out in the beginning moments of our universe. Initially, the gravitational attraction from curved space would overcome torsion's repulsive forces, serving to collapse matter into smaller regions of space. But eventually torsion would become very strong and prevent matter from compressing into a point of infinite density; matter would reach a state of extremely large but finite density. As energy can be converted into mass, the immensely high gravitational energy in this extremely dense state would cause an intense production of particles, greatly increasing the mass inside the black hole.
The increasing numbers of particles with spin would result in higher levels of spacetime torsion. The repulsive torsion would stop the collapse and would create a "big bounce" like a compressed beach ball that snaps outward. The rapid recoil after such a big bounce could be what has led to our expanding universe. The result of this recoil matches observations of the universe's shape, geometry, and distribution of mass.
In turn, the torsion mechanism suggests an astonishing scenario: every black hole would produce a new, baby universe inside. If that is true, then the first matter in our universe came from somewhere else. So our own universe could be the interior of a black hole existing in another universe. Just as we cannot see what is going on inside black holes in the cosmos, any observers in the parent universe could not see what is going on in ours.
The motion of matter through the black hole's boundary, called an "event horizon," would only happen in one direction, providing a direction of time that we perceive as moving forward. The arrow of time in our universe would therefore be inherited, through torsion, from the parent universe.
Torsion could also explain the observed imbalance between matter and antimatter in the universe. Because of torsion, matter would decay into familiar electrons and quarks, and antimatter would decay into "dark matter," a mysterious invisible form of matter that appears to account for a majority of matter in the universe.
Finally, torsion could be the source of "dark energy," a mysterious form of energy that permeates all of space and increases the rate of expansion of the universe. Geometry with torsion naturally produces a "cosmological constant," a sort of added-on outward force which is the simplest way to explain dark energy. Thus, the observed accelerating expansion of the universe may end up being the strongest evidence for torsion.
Torsion therefore provides a theoretical foundation for a scenario in which the interior of every black hole becomes a new universe. It also appears as a remedy to several major problems of current theory of gravity and cosmology. Physicists still need to combine the Einstein-Cartan-Sciama-Kibble theory fully with quantum mechanics into a quantum theory of gravity. While resolving some major questions, it raises new ones of its own. For example, what do we know about the parent universe and the black hole inside which our own universe resides? How many layers of parent universes would we have? How can we test that our universe lives in a black hole?
The last question can potentially be investigated: since all stars and thus black holes rotate, our universe would have inherited the parent black hole’s axis of rotation as a "preferred direction." There is some recently reported evidence from surveys of over 15,000 galaxies that in one hemisphere of the universe more spiral galaxies are "left-handed", or rotating clockwise, while in the other hemisphere more are "right-handed", or rotating counterclockwise. In any case, I believe that including torsion in geometry of spacetime is a right step towards a successful theory of cosmology.

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White Dwarf Stars to Collide in Catastrophic Supernova

Henize 2-428 nebula
Pictured: An artist's impression of the center of the Henize 2-428 planetary nebula, containing two white dwarf stars. (Photo : ESO/L. CALÇADA)


Excerpt from natureworldnews.com

Reported in the journal Nature, the European Southern Observatory's (ESO) Very Large Telescope (VLT) in Chile was originally studying how some stars produce strangely shaped, asymmetric nebula. They focused on Henize 2-428 and found something they did not expect - not just one star, but two.

"Further observations made with telescopes in the Canary Islands allowed us to determine the orbit of the two stars and deduce both the masses of the two stars and their separation. This was when the biggest surprise was revealed," co-author Romano Corradi, a researcher at the Instituto de Astrofísica de Canarias, said in a press release.

The next shocker was that the two stars were white dwarfs - tiny, extremely dense stars with a total mass about 1.8 times that of the Sun. The fact that there are two stars supports the theory that double central stars may explain the odd shapes of some of these nebulae.

They've also found that the stars orbit every 4 hours and due to the emission of gravitational waves, they are slowly spiraling into one another. Within the next 700 million years, these stars will merge and under the stress of their combined mass, explode in a giant supernova.

"Until now, the formation of supernovae Type Ia by the merging of two white dwarfs was purely theoretical," said co-author David Jones, an ESO Fellow at the time the data were obtained. "The pair of stars in Henize 2-428 is the real thing!"

"It's an extremely enigmatic system," added lead researcher Santander-García. "It will have important repercussions for the study of supernovae Type Ia, which are widely used to measure astronomical distances and were key to the discovery that the expansion of the Universe is accelerating due to dark energy."

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Theoretical physics: The origins of space and time


Excerpt from nature.com
By Zeeya Merali


Many researchers believe that physics will not be complete until it can explain not just the behaviour of space and time, but where these entities come from.

“Imagine waking up one day and realizing that you actually live inside a computer game,” says Mark Van Raamsdonk, describing what sounds like a pitch for a science-fiction film. But for Van Raamsdonk, a physicist at the University of British Columbia in Vancouver, Canada, this scenario is a way to think about reality. If it is true, he says, “everything around us — the whole three-dimensional physical world — is an illusion born from information encoded elsewhere, on a two-dimensional chip”. That would make our Universe, with its three spatial dimensions, a kind of hologram, projected from a substrate that exists only in lower dimensions.

This 'holographic principle' is strange even by the usual standards of theoretical physics. But Van Raamsdonk is one of a small band of researchers who think that the usual ideas are not yet strange enough. If nothing else, they say, neither of the two great pillars of modern physics — general relativity, which describes gravity as a curvature of space and time, and quantum mechanics, which governs the atomic realm — gives any account for the existence of space and time. Neither does string theory, which describes elementary threads of energy.

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Zeeya Merali discusses some of the theories that are trying to explain the origins of space and time.


Van Raamsdonk and his colleagues are convinced that physics will not be complete until it can explain how space and time emerge from something more fundamental — a project that will require concepts at least as audacious as holography. They argue that such a radical reconceptualization of reality is the only way to explain what happens when the infinitely dense 'singularity' at the core of a black hole distorts the fabric of space-time beyond all recognition, or how researchers can unify atomic-level quantum theory and planet-level general relativity — a project that has resisted theorists' efforts for generations.

“All our experiences tell us we shouldn't have two dramatically different conceptions of reality — there must be one huge overarching theory,” says Abhay Ashtekar, a physicist at Pennsylvania State University in University Park.

Finding that one huge theory is a daunting challenge. Here, Nature explores some promising lines of attack — as well as some of the emerging ideas about how to test these concepts...

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The (Not So) Curious Case of Galaxy IC 335

This odd-looking galaxy has recently become famous in the media, not for what it has but for what is missing!Excerpt from huffingtonpost.comA recent Hubble image of this galaxy shows it to be a star-filled galaxy with a flat shape not unlike our own M...

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Dinosaur Researchers Say They’re in a ‘Golden Age’ of Discovery Due to the ‘Jurassic Park’ effect




Excerpt from nbcnews.com

This was a great year for dinosaurs. Dreadnoughtus, "Jar Jar Binks," and a swimming Spinosaurus all made headlines — and 2015 could hold even more surprises. 

It wasn't always like this. From 1984 to 1994, there were about 15 new dinosaur species named per year. This year, nearly one species was discovered every week. 

"We're absolutely in a golden age of dinosaur discovery," David Evans, who oversees dinosaur research at the Royal Ontario Museum, told NBC News. "It is probably a better time to be a dinosaur paleontologist now than any other time in the last century." 

The 'Jurassic Park' effect

When it comes to finding dinosaurs in the dirt, paleontologists are using the same tools that they were 30 years ago. Satellite images might give them a better view of dig sites, but for the most part the process has not changed much. 

So why are there so many dinosaur discoveries these days? More people are looking for them. Evans estimates that the number of dinosaur paleontologists has more than quadrupled in the last 30 years. 

Every paleontologist interviewed for this story pointed to one catalyst for the paleontology boom: Steven Spielberg's 1993 blockbuster "Jurassic Park." 

"It put the most lifelike, scientifically accurate dinosaurs ever on the big screen," Evans said. "That helped the public moved beyond the classical view of dinosaurs as slow, dim-twitted creatures."
Famed Montana State University paleontologist Jack Horner admits he has a special affection for the film. He served as scientific adviser for the original "Jurassic Park" and was the inspiration for Dr. Alan Grant, the movie's protagonist. He also consulted on the upcoming "Jurassic World" starring Chris Pratt.

"'Jurassic Park' attracted an incredible number of people to the field," Horner told NBC News. "I'm hoping that we put together something cool with 'Jurassic World' that people will really like and get more children interested in paleontology." 

Increased interest led to increased paleontology budgets for museums and universities, Evans said. That has made a big difference in places like China and Argentina, relatively unexplored areas where a new generation of paleontologists has unearthed most of the recent headline-grabbing discoveries. 

"The number of dinosaur researchers is much higher now than in the '90s," Thomas Holtz, a vertebrate paleontologist at the University of Maryland, told NBC News. "Anytime you are exploring a region and a slice of time that hasn't been sampled before, chances are that everything you are finding is new."

2014 and beyond

Some of the biggest discoveries of the year were not new species. Instead, they were more complete fossils of dinosaurs the scientific community knew very little about. 

Take Spinosaurus, a massive carnivore that was even bigger than Tyrannosaurus rex. While its teeth indicated it ate fish, scientists were divided on whether it roamed the land and water looking for prey.

This year, the matter was settled. A new paper showed that the dinosaur's unique body structure — tiny hind limbs, dense bones, crocodile-like receptors in its snout — was best suited for the water and caused it to waddle on land. 

"That was probably the most significant find of the year," Horner said. 

There were other big discoveries in 2014. Dreadnoughtus fossils discovered in Argentina belonged to a creature that measured 85 feet (26 meters) long and weighed about 65 tons (59 metric tons), or about as much as a dozen elephants. 


Image: Deinocheirus mirificus, the largest known member of a group of ostrich-like dinosaurs 
This undated handout image provided by Michael Skrepnick, Dinosaurs in Art, Nature Publishing Group, shows a Deinocheirus mirificus, the largest known member of a group of bird-like dinosaurs.

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Discovery Sparks Interest – NASA’s Mission to Mars Gets Its Own New Show

Excerpt from sciencetimes.comOften in the media, it's what's new and fresh that brings in the ratings. But what about looking for something potentially millions of years old? What if it wasn't on this planet even? Peak your interest yet? Well, if so...

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Ripples in Space-Time Could Reveal ‘Strange Stars’


Two Neutron Stars Collide
Scene from a NASA animation showing two neutron stars colliding.



Excerpt from
space.com 

By looking for ripples in the fabric of space-time, scientists could soon detect "strange stars" — objects made of stuff radically different from the particles that make up ordinary matter, researchers say.

The protons and neutrons that make up the nuclei of atoms are made of more basic particles known as quarks. There are six types, or "flavors," of quarks: up, down, top, bottom, charm and strange. Each proton or neutron is made of three quarks: Each proton is composed of two up quarks and one down quark, and each neutron is made of two down quarks and one up quark.

In theory, matter can be made with other flavors of quarks as well. Since the 1970s, scientists have suggested that particles of "strange matter" known as strangelets — made of equal numbers of up, down and strange quarks — could exist. In principle, strange matter should be heavier and more stable than normal matter, and might even be capable of converting ordinary matter it comes in contact with into strange matter. However, lab experiments have not yet created any strange matter, so its existence remains uncertain. 


One place strange matter could naturally be created is inside neutron stars, the remnants of stars that died in catastrophic explosions known as supernovas. Neutron stars are typically small, with diameters of about 12 miles (19 kilometers) or so, but are so dense that they weigh as much as the sun. A chunk of a neutron star the size of a sugar cube can weigh as much as 100 million tons.

Under the extraordinary force of this extreme weight, some of the up and down quarks that make up neutron stars could get converted into strange quarks, leading to strange stars made of strange matter, researchers say.

A strange star that occasionally spurts out strange matter could quickly convert a neutron star orbiting it in a binary system into a strange star as well. Prior research suggests that a neutron star that receives a seed of strange matter from a companion strange star could transition to a strange star in just 1 millisecond to 1 second.
Now, researchers suggest they could detect strange stars by looking for the stars' gravitational waves — invisible ripples in space-time first proposed by Albert Einstein as part of his theory of general relativity.

Gravitational waves are emitted by accelerating masses. Really big gravitational waves are emitted by really big masses, such as pairs of neutron stars merging with one another.

Pairs of strange stars should give off gravitational waves that are different from those emitted by pairs of "normal" neutron stars because strange stars should be more compact, researchers said. For instance, a neutron star with a mass one-fifth that of the sun should be more than 18 miles (30 km) in diameter, whereas a strange star of the same mass should be a maximum of 6 miles (10 km) wide.
The researchers suggest that events involving strange stars could explain two short gamma-ray bursts — giant explosions lasting less than 2 seconds — seen in deep space in 2005 and 2007. The Laser Interferometer Gravitational-Wave Observatory (LIGO) did not detect gravitational waves from either of these events, dubbed GRB 051103 and GRB 070201.

Neutron star mergers are the leading explanations for short gamma-ray bursts, but LIGO should, in principle, have detected gravitational waves from such mergers. However, if strange stars were involved in both of these events, LIGO would not have been able to detect any gravitational waves they emitted, researchers said. (The more compact a star is within a binary system of two stars, the higher the frequency of the gravitational waves it gives off.)

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