Excerpt from techtimes.com Interstellar may be attracting viewers to the movies at warp speed, but wormholes like the one featured in the new film are likely a reality, deep in space.The movie Interstellar follows a group of astronauts who...
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Excerpt from bostonglobe.com
Decades after that first small step, space thinkers are finally getting serious about our nearest neighbor By Kevin Hartnett
This week, the European Space Agency made headlines with the first successful landing of a spacecraft on a comet, 317 million miles from Earth. It was an upbeat moment after two American crashes: the unmanned private rocket that exploded on its way to resupply the International Space Station, and the Virgin Galactic spaceplane that crashed in the Mojave Desert, killing a pilot and raising questions about whether individual businesses are up to the task of operating in space. During this same period, there was one other piece of space news, one far less widely reported in the United States: On Nov. 1, China successfully returned a moon probe to Earth. That mission follows China’s landing of the Yutu moon rover late last year, and its announcement that it will conduct a sample-return mission to the moon in 2017. With NASA and the Europeans focused on robot exploration of distant targets, a moon landing might not seem like a big deal: We’ve been there, and other countries are just catching up. But in recent years, interest in the moon has begun to percolate again, both in the United States and abroad—and it’s catalyzing a surprisingly diverse set of plans for how our nearby satellite will contribute to our space future. China, India, and Japan have all completed lunar missions in the last decade, and have more in mind. Both China and Japan want to build unmanned bases in the early part of the next decade as a prelude to returning a human to the moon. In the United States, meanwhile, entrepreneurs are hatching plans for lunar commerce; one company even promises to ferry freight for paying customers to the moon as early as next year. Scientists are hatching more far-out ideas to mine hydrogen from the poles and build colonies deep in sky-lit lunar caves. This rush of activity has been spurred in part by the Google Lunar X Prize, a $20 million award, expiring in 2015, for the first private team to land a working rover on the moon and prove it by sending back video. It is also driven by a certain understanding: If we really want to launch expeditions deeper into space, our first goal should be to travel safely to the moon—and maybe even figure out how to live there.
Entrepreneurial visions of opening the moon to commerce can seem fanciful, especially in light of the Virgin Galactic and Orbital Sciences crashes, which remind us how far we are from having a truly functional space economy. They also face an uncertain legal environment—in a sense, space belongs to everyone and to no one—whose boundaries will be tested as soon as missions start to succeed. Still, as these plans take shape, they’re a reminder that leaping blindly is sometimes a necessary step in opening any new frontier.
“All I can say is if lunar commerce is foolish,” said Columbia University astrophysicist Arlin Crotts in an e-mail, “there are a lot of industrious and dedicated fools out there!”
At its height, the Apollo program accounted for more than 4 percent of the federal budget. Today, with a mothballed shuttle and a downscaled space station, it can seem almost imaginary that humans actually walked on the moon and came back—and that we did it in the age of adding machines and rotary phones.
“In five years, we jumped into the middle of the 21st century,” says Roger Handberg, a political scientist who studies space policy at the University of Central Florida, speaking of the Apollo program. “No one thought that 40 years later we’d be in a situation where the International Space Station is the height of our ambition.”
NASA/JPL/Northwestern University
An image of Earth and the moon created from photos by Mariner 10, launched in 1973.Without a clear goal and a geopolitical rivalry to drive it, the space program had to compete with a lot of other national priorities. The dramatic moon shot became an outlier in the longer, slower story of building scientific achievements.
Now, as those achievements accumulate, the moon is coming back into the picture. For a variety of reasons, it’s pretty much guaranteed to play a central role in any meaningful excursions we take into space. It’s the nearest planetary body to our own—238,900 miles away, which the Apollo voyages covered in three days. It has low gravity, which makes it relatively easy to get onto and off of the lunar surface, and it has no atmosphere, which allows telescopes a clearer view into deep space.
The moon itself also still holds some scientific mysteries. A 2007 report on the future of lunar exploration from the National Academies called the moon a place of “profound scientific value,” pointing out that it’s a unique place to study how planets formed, including ours. The surface of the moon is incredibly stable—no tectonic plates, no active volcanoes, no wind, no rain—which means that the loose rock, or regolith, on the moon’s surface looks the way the surface of the earth might have looked billions of years ago.
NASA still launches regular orbital missions to the moon, but its focus is on more distant points. (In a 2010 speech, President Obama brushed off the moon, saying, “We’ve been there before.”) For emerging space powers, though, the moon is still the trophy destination that it was for the United States and the Soviet Union in the 1960s. In 2008 an Indian probe relayed the best evidence yet that there’s water on the moon, locked in ice deep in craters at the lunar poles. China landed a rover on the surface of the moon in December 2013, though it soon malfunctioned. Despite that setback, China plans a sample-return mission in 2017, which would be the first since a Soviet capsule brought back 6 ounces of lunar soil in 1976.
The moon has also drawn the attention of space-minded entrepreneurs. One of the most obvious opportunities is to deliver scientific instruments for government agencies and universities. This is an attractive, ready clientele in theory, explains Paul Spudis, a scientist at the Lunar and Planetary Institute in Houston, though there’s a hitch: “The basic problem with that as a market,” he says, “is scientists never have money of their own.”
One company aspiring to the delivery role is Astrobotic, a startup of young Carnegie Mellon engineers based in Pittsburgh, which is currently positioning itself to be “FedEx to the moon,” says John Thornton, the company’s CEO. Astrobotic has signed a contract with SpaceX, the commercial space firm founded by Elon Musk, to use a Falcon 9 for an inaugural delivery trip in 2015, just in time to claim the Google Lunar X Prize. Thornton says most of the technology is in place for the mission, and that the biggest remaining hurdle is figuring out how to engineer a soft, automated moon landing.
Astrobotic is charging $1.2 million per kilogram—you can, in fact, place an order on its website—and Thornton says the company has five customers so far. They include the entities you might expect, like NASA, but also less obvious ones, like a company that wants to deliver human ashes for permanent internment and a Japanese soft drink manufacturer that wants to place its signature beverage, Pocari Sweat, on the moon as a publicity stunt. Astrobotic is joined in this small sci-fi economy by Moon Express out of Mountain View, Calif., another company competing for the Google Lunar X Prize.
Plans like these are the low-hanging fruit of the lunar economy, the easiest ideas to imagine and execute. Longer-scale thinkers are envisioning ways that the moon will play a larger role in human affairs—and that, says Crotts, is where “serious resource exploitation” comes in.
If this triggers fears of a mined-out moon, be reassured: “Apollo went there and found nothing we wanted. Had we found anything we really wanted, we would have gone back and there would have been a new gold rush,” says Roger Launius, the former chief historian of NASA and now a curator at the National Air and Space Museum.
There is one possible exception: helium-3, an isotope used in nuclear fusion research. It is rare on Earth but thought to be abundant on the surface of the moon, which could make the moon an important energy source if we ever figure out how to harness fusion energy. More immediately intriguing is the billion tons of water ice the scientific community increasingly believes is stored at the poles. If it’s there, that opens the possibility of sustained lunar settlement—the water could be consumed as a liquid, or split into oxygen for breathing and hydrogen for fuel.
The presence of water could also open a potentially ripe market providing services to the multibillion dollar geosynchronous satellite industry. “We lose billions of dollars a year of geosynchronous satellites because they drift out of orbit,” says Crotts. In a new book, “The New Moon: Water, Exploration, and Future Habitation,” he outlines plans for what he calls a “cislunar tug”: a space tugboat of sorts that would commute between the moon and orbiting satellites, resupplying them with propellant, derived from the hydrogen in water, and nudging them back into the correct orbital position.
In the long term, the truly irreplaceable value of the moon may lie elsewhere, as a staging area for expeditions deeper into space. The most expensive and dangerous part of space travel is lifting cargo out of and back into the Earth’s atmosphere, and some people imagine cutting out those steps by establishing a permanent base on the moon. In this scenario, we’d build lunar colonies deep in natural caves in order to escape the micrometeorites and toxic doses of solar radiation that bombard the moon, all the while preparing for trips to more distant points.
gical hurdles is long, and there’s also a legal one, at least where commerce is concerned. The moon falls under the purview of the Outer Space Treaty, which the United States signed in 1967, and which prohibits countries from claiming any territory on the moon—or anywhere else in space—as their own.
“It is totally unclear whether a private sector entity can extract resources from the moon and gain title or property rights to it,” says Joanne Gabrynowicz, an expert on space law and currently a visiting professor at Beijing Institute of Technology School of Law. She adds that a later document, the 1979 Moon Treaty, which the United States has not signed, anticipates mining on the moon, but leaves open the question of how property rights would be determined.
There are lots of reasons the moon may never realize its potential to mint the world’s first trillionaires, as some space enthusiasts have predicted. But to the most dedicated space entrepreneurs, the economic and legal arguments reflect short-sighted thinking. They point out that when European explorers set sail in the 15th and 16th centuries, they assumed they’d find a fortune in gold waiting for them on the other side of the Atlantic. The real prizes ended up being very different—and slow to materialize.
“When we settled the New World, we didn’t bring a whole lot back to Europe [at first],” Thornton says. “You have to create infrastructure to enable that kind of transfer of goods.” He believes that in the case of the moon, we’ll figure out how to do that eventually.
Roger Handberg is as clear-eyed as anyone about the reasons why the moon may never become more than an object of wonder, but he also understands why we can’t turn away from it completely. That challenge, in the end, may finally be what lures us back.
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| These infrared images of the planet Uranus show a white spot that is actually a massive storm on the planet. This image was recorded by the Keck II telescope atop Mauna Kea in Hawaii on Aug. 6, 2014 in the 2.2-micron wavelength. |
Excerpt from space.com
By Elizabeth Howell
Uranus is finally having some summer storms, seven years after the planet reached its closest approach to the sun, leaving scientists wondering why the massive storms are so late.
The usually quiet gas giant now has such "incredibly active" weather that some of the features are even visible to amateurs, said Imke de Pater, the project's lead researcher and an astronomer at the University of California, Berkeley. Astronomers first announced the extreme storms on Uranus in August, and have been trying to understand them ever since.
This is by far the most active weather de Pater's team has seen on Uranus in the past decade, examining its storms and northern convective features. It also paints a different picture of the quiet planet Voyager 2 saw when the NASA spacecraft flew by in 1986.
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| An infrared composite image of the two hemispheres of Uranus obtained with Keck Telescope adaptive optics. The component colors of blue, green, and red were obtained from images made at near infrared wavelengths of 1.26, 1.62, and 2.1 microns respectively. The images were obtained on July 11 and 12, 2004. The North pole is at 4 o'clock. Lawrence Sromovsky, University of Wisconsin-Madison/W.W. Keck Observatory |
But here's where the mystery comes in: As far as anyone can tell, Uranus has no source of internal heat. Sunlight is thought to be responsible for changes in its atmosphere, such as storms. But the sun's light is currently weak in Uranus' northern hemisphere, so scientists are puzzled as to why that area is so active today.
Huge storms on Uranus
Based on the colors and structure of the storm spotted by amateurs, professional astronomers believe it could hint at a vortex deeper in the atmosphere — similar to phenomena spotted on Jupiter, such as the Great Red Spot.
Follow-up observations with the Keck II telescope revealed that the storm was still raging, although it had changed its shape, and possibly its intensity.
Also contributing to the effort was the Hubble Space Telescope, which examined the entire planet of Uranus Oct. 14 in several wavelengths. The observations revealed storms spanning several altitudes, over a distance of about 5,592 miles (9,000 kilometers).
"If, indeed, these features are high-altitude clouds generated by flow perturbations associated with a deeper vortex system, such drastic fluctuations in intensity would indeed be possible," said Larry Sromovsky, a planetary scientist at the University of Wisconsin-Madison who performed the newer work.
Excerpt from telegraph.co.uk
By Rhiannon Williams
Travelling through time, invisibility cloaks and teleporting could all happen within today's children's lifetimes, experts have predicted
Children could be travelling between centuries as soon as the year 2100, while teleportation could become a regular occurence by around 2080, professors from Imperial College London and the University of Glasgow have said.
"The good thing about teleportation is that there is no fundamental law telling us that it cannot be done and with technical advances I would estimate teleportation that we see in the films will be with us by 2080,” said Dr. Mary Jacquiline Romero from the School of Physics and Astronomy, University of Glasgow.
“Teleporting a person, atom by atom, will be very difficult and is of course a physicist's way, but perhaps developments in chemistry or molecular biology will allow us to do it more quickly. The good thing about teleportation is that there is no fundamental law telling us that it cannot be done and with technical advances I would estimate teleportation that we see in the films will be with us by 2080,” she said.
“Time travel to the future has already been achieved, but only in tiny amounts. The record is 0.02 seconds set by cosmonaut Sergei Krikalev. Whilst that doesn't sound too impressive, it does show that time travel to the future is possible and that the amount of time travel couldn't be far greater," he argued. “If you travelled through space on a big loop at 10 per cent the speed of light for what seemed to you like six months, approximately six months and one day would have passed on Earth. You'd have time travelled a day into the future. Travel at the same speed for 10 years and you'll time travel nearly three weeks into the future. I would say we are looking at 2100 as a very optimistic timescale for travelling weeks into the future.”
Invisibility cloaks, as featured in Harry Potter, could be "entirely feasible" within the next 10 to 20 years, Professor Chris Phillips, Professor of Experimental Solid State Physics at Imperial College London said.
Harry tests his invisibility cloak for the first time
“One way to create an ‘invisibility cloak’ is to use adaptive camouflage, which involves taking a film of the background of an object or person and projecting it onto the front to give the illusion of vanishing, " he added.
"We’re actually not that far away from this becoming a reality – rudimentary technology versions of this have already been created – but the main problem is that the fibre-like structures in the adaptive camouflage need to be so tightly woven that it’s incredibly labour intensive. With developments such as 3D printing allowing us to create previously impossible materials, it’s entirely feasible that we could see a ‘Harry Potter’-like invisibility cloak within the next 10 to 20 years.”
The research was conducted by the Big Bang UK Young Scientists and Engineers Fair, which compared the predictions of scientists to that of a panel of 11-16 year-olds.
While their speculation was largely in line with the experts' expectations, the children thought time travel could be feasible by 2078. They also dramatically overestimated when they might be able to become space tourists - anticipating it might take another 30 years, when commercial space flights are due to launch in 2015.
Excerpt from sciencetimes.comWhile space junkies have been ravenous this past summer with all the stellar lunar events in the sky, from the super moon trilogy to the blood moon earlier this month, experts at NASA are excited this week about a...
NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washingtonnasa.govMESSENGER Finds New Evidence for Water Ice at Mercury's Poles Mercury's North Polar Region Acquired By The Arecibo Observatory A Mosaic of MESSEN...
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Photo By NOAA/AP This image provided by NOAA Wednesday Oct. 15, 2014 shows Hurricane Gonzalo, lower right, which forecasters said could become a powerful category 4 storm Wednesday as it heads toward Bermuda. The storm had top sustained winds of 125 mph (205 kph) and was centered about 665 miles (1,075 kilometers) south of Bermuda early Wednesday, the U.S. National Hurricane Center said. It was moving northwest at 13 mph (20 kph). |
HAMILTON, Bermuda (AP) — People on this small British territory are hurrying to batten down for Hurricane Gonzalo, which is churning toward them as a major Category 3 storm just days after a tropical storm damaged homes and knocked down trees and power lines in Bermuda.
Dennis Feltgen, a meteorologist at the U.S. National Hurricane Center in Miami, said it was too early to tell whether the hurricane would actually hit Bermuda sometime Friday, but he warned residents to be prepared for severe weather.
"The eye of the hurricane does not have to go over Bermuda for them not to experience severe conditions," he said in a phone interview Wednesday.
Gonzalo had top sustained winds of 120 mph (195 kph) late Wednesday and it was centered about 580 miles (935 kilometers) south-southwest of Bermuda. It was moving north at 9 mph (15 kph), the hurricane center said. Gonzalo grew into a powerful Category 4 storm at one point Wednesday, but weakened a bit later in the day.
A hurricane warning was in effect for Bermuda, and forecasters said a dangerous storm surge could cause significant flooding on the island, which has some 64 miles (103 kilometers) of shoreline and has an area about one-third the size of Washington, D.C. Some 3 to 6 inches (8 to 15 centimeters) of rain was predicted.
The government said it would close the island's international airport Thursday night, when tropical storm conditions were first expected. Several airlines increased the number of flights departing Bermuda ahead of the storm.
dailymail.co.uk
Earlier this year Professor Stephen Hawking shocked physicists by saying 'there are no black holes'.
In a paper published online, Professor Hawking instead argues there are 'grey holes'
'The absence of event horizons means that there are no black holes - in the sense of regimes from which light can't escape to infinity,' he says in the paper, called Information Preservation and Weather Forecasting For Black Holes.
He says that the idea of an event horizon, from which light cannot escape, is flawed.
He suggests that instead light rays attempting to rush away from the black hole’s core will be held as though stuck on a treadmill and that they can slowly shrink by spewing out radiation.
One of the reasons black holes are so bizarre is that they pit two fundamental theories of the universe against each other.
Namely, Einstein’s theory of gravity predicts the formation of black holes. But a fundamental law of quantum theory states that no information from the universe can ever disappear.
Efforts to combine these two theories proved problematic, and has become known as the black hole information paradox - how can matter permanently disappear in a black hole as predicted?
Professor Mersini-Houghton’s new theory does manage to mathematically combine the two fundamental theories, but with unwanted effects for people expecting black holes to exist.
‘Physicists have been trying to merge these two theories - Einstein’s theory of gravity and quantum mechanics - for decades, but this scenario brings these two theories together, into harmony,’ said Professor Mersini-Houghton.
‘And that’s a big deal.’
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| Human brains are about three times as large as those of our early australopithecines ancestors that lived 4 million to 2 million years ago, and for years, scientists have wondered how our brains got so big. A new study suggests social competition could be behind the increase in brain size. Credit NIH, NADA |
livescience.com
There are many ways to try to explain why human brains today are so big compared to those of early humans, but the major cause may be social competition, new research suggests.But with several competing ideas, the issue remains a matter of debate.
Compared to almost all other animals, human brains are larger as a percentage of body weight. And since the emergence of the first species in our Homo genus (Homo habilis) about 2 million years ago, the human brain has doubled in size. And when compared to earlier ancestors, such as australopithecines that lived 4 million to 2 million years ago, our brains are three times as large. For years, scientists have wondered what could account for this increase.
Behind the hypotheses
The climate idea proposes that dealing with unpredictable weather and major climate shifts may have increased the ability of our ancestors to think ahead and prepare for these environmental changes, which in turn led to a larger, more cognitively adept brain.
The ecology hypothesis states that, as our ancestors migrated away from the equator, they encountered environmental changes, such as less food and other resources. "So you have to be a little bit more clever to figure it out," said David Geary, a professor from the University of Missouri. Also, less parasite exposure could have played a role in the makings of a bigger brain. When your body combats parasites, it cranks up its immune system, which uses up calories that could have gone to boost brain development. Since there are fewer parasites farther away from the equator, migrating north or south could have meant that our predecessors had more opportunity to grow a larger brain because their bodies were not fighting off as many pathogens.
Finally, other researchers think that social competition for scarce resources influenced brain size. As populations grow, more people are contesting for the same number of resources, the thinking goes. Those with a higher social status, who are "a little bit smarter than other folks" will have more access to food and other goods, and their offspring will have a higher chance of survival, Geary said.
Those who are not as socially adept will die off, pushing up the average social "fitness" of the group. "It's that type of process, that competition within a species, for status, for control of resources, that cycles over and over again through multiple generations, that is a process that could easily explain a very, very rapid increase in brain size," Geary said.
Weighing the options
To examine which hypothesis is more likely, Geary and graduate student Drew Bailey analyzed data from 175 skull fossils — from humans and our ancestors — that date back to sometime between 10,000 ago and 2 million years ago.
The team looked at multiple factors, including how old the fossils were, where they were found, what the temperature was and how much the temperature varied at the time the Homo species lived, and the level of parasites in the area. They also looked at the population density of the region in order to measure social competition, "assuming that the more fossils you find in a particular area at a particular time, the more likely the population was larger," Geary said.
They then used a statistical analysis to test all of the variables at once to see how well they predicted brain size. "By far the best predictor was population density," Geary said. "And in fact, it seemed that there was very little change in brain size across our sample of fossil skulls until we hit a certain population size. Once that population density was hit, there was a very quick increase in brain size," he said.
Looking at all the variables together allowed the researchers to "separate out which variables are really important and which variables may be correlated for other reasons," added Geary. While the climate variables were still significant, their importance was much lower than that of population density, he said. The results were published in the March 2009 issue of the journal Human Nature.
Questions linger
The social competition hypothesis "sounds good," said Ralph Holloway, an anthropologist at Columbia University, who studies human brain evolution. But, he adds: "How would you ever go about really testing that with hard data?"
He points out that the sparse cranium data "doesn’t tell you anything about the differences in populations for Homo erectus, or the differences in populations of Neanderthals." For example, the number of Homo erectus crania that have been found in Africa, Asia, Indonesia and parts of Europe is fewer than 25, and represent the population over hundreds of thousands of years, he said.
"You can't even know the variation within a group let alone be certain of differences between groups," Holloway said. Larger skulls would be considered successful, but "how would you be able to show that these were in competition?"
However, Holloway is supportive of the research. "I think these are great ideas that really should be pursued a little bit more," he said.
Alternative hypotheses
Holloway has another hypothesis for how our brains got so big. He thinks that perhaps increased gestation time in the womb or increased dependency time of children on adults could have a played role. The longer gestation or dependency time "would have required more social cooperation and cognitive sophistication on the part of the parents," he said. Males and females would have needed to differentiate their social roles in a complementary way to help nurture the child. The higher level of cognition needed to perform these tasks could have led to an increase in brain size.
Still other hypotheses look at diet as a factor. Some researchers think that diets high in fish and shellfish could have provided our ancestors with the proper nutrients they needed to grow a big brain.
And another idea is that a decreased rate of cell death may have allowed more brain neurons to be synthesized, leading to bigger noggins.
Ultimately, no theory can be absolutely proven, and the scant fossil record makes it hard to test hypotheses. "If you calculate a generation as, let's say, 20 years, and you know that any group has to have a minimal breeding size, then the number of fossils that we have that demonstrates hominid evolution is something like 0.000001 percent," Holloway said. "So frankly, I mean, all hypotheses look good."
dailymail.co.uk
By Jonathan O’Callaghan
- Scientist claims she has mathematical proof black holes cannot exist
- She said it is impossible for stars to collapse and form a singularity
- Professor Laura Mersini-Houghton said she is still in 'shock' from the find
- Previously, scientists thought stars much larger than the sun collapsed under their own gravity and formed black holes when they died
- During this process they release a type of radiation called Hawking radiation
- But new research claims the star would lose too much mass and wouldn't be able to form a black hole
- If true, the theory that the universe began as a singularity, followed by the Big Bang, could also be wrong
- When a huge star many times the mass of the sun comes to the end of its life it collapses in on itself and forms a singularity – creating a black hole where gravity is so strong that not even light itself can escape.At least, that’s what we thought.A scientist has sensationally said that it is impossible for black holes to exist – and she even has mathematical proof to back up her claims.If true, her research could force physicists to scrap their theories of how the universe began.
A scientist from University of North Carolina states she has mathematical proof that black holes (illustrated) can’t exist. She said it is impossible for stars to collapse and form a singularity. Previously, scientists thought stars larger than the sun collapsed under their own gravity and formed black holes as they diedThe research was conducted by Professor Laura Mersini-Houghton from the University of North Carolina at Chapel Hill in the College of Arts and Scientists.She claims that as a star dies, it releases a type of radiation known as Hawking radiation – predicted by Professor Stephen Hawking.THE BLACK HOLE INFORMATION PARADOX
One of the biggest unanswered questions about black holes is the so-called information paradox.Under current theories for black holes it is thought that nothing can escape from the event horizon around a black hole – not even light itself.Inside the black hole is thought to be a singularity where matter is crushed to an infinitesimally small point as predicted by Einstein’s theory of gravity.However, a fundamental law of quantum theory states that no information from the universe can ever disappear.This creates a paradox; how can a black hole make matter and information ‘disappear’?Professor Mersini-Houghton’s new theory manages to explain why this might be so – namely because black holes as we know them cannot exist.However in this process, Professor Mersini-Houghton believes the star also sheds mass, so much so that it no longer has the density to become a black hole.Before the black hole can form, she said, the dying star swells and explodes.The singularity as predicted never forms, and neither does the event horizon – the boundary of the black hole where not even light can escape.‘I’m still not over the shock,’ said Professor Mersini-Houghton.‘We’ve been studying this problem for a more than 50 years and this solution gives us a lot to think about.’Experimental evidence may one day provide physical proof as to whether or not black holes exist in the universe.But for now, Mersini-Houghton says the mathematics are conclusive.What’s more, the research could apparently even call into question the veracity of the Big Bang theory.Most physicists think the universe originated from a singularity that began expanding with the Big Bang about 13.8 billion years ago.If it is impossible for singularities to exist, however, as partially predicted by Professor Mersini-Houghton, then that theory would also be brought into question.
During the collapse process stars release a type of radiation called Hawking radiation (shown). But Professor Mersini-Houghton claims this process means the star loses too much mass and can’t form a black hole. And this also apparently means the Big Bang theory, that the universe began as a singularity, may not be correctTHERE ARE NO BLACK HOLES, ONLY GREY HOLES, CLAIMS HAWKING
Earlier this year Professor Stephen Hawking shocked physicists by saying ‘there are no black holes’.In a paper published online, Professor Hawking instead argues there are ‘grey holes’‘The absence of event horizons means that there are no black holes – in the sense of regimes from which light can’t escape to infinity,’ he says in the paper, called Information Preservation and Weather Forecasting For Black Holes.He says that the idea of an event horizon, from which light cannot escape, is flawed.He suggests that instead light rays attempting to rush away from the black hole’s core will be held as though stuck on a treadmill and that they can slowly shrink by spewing out radiation.One of the reasons black holes are so bizarre is that they pit two fundamental theories of the universe against each other.Namely, Einstein’s theory of gravity predicts the formation of black holes. But a fundamental law of quantum theory states that no information from the universe can ever disappear.Efforts to combine these two theories proved problematic, and has become known as the black hole information paradox – how can matter permanently disappear in a black hole as predicted?Professor Mersini-Houghton’s new theory does manage to mathematically combine the two fundamental theories, but with unwanted effects for people expecting black holes to exist.‘Physicists have been trying to merge these two theories – Einstein’s theory of gravity and quantum mechanics – for decades, but this scenario brings these two theories together, into harmony,’ said Professor Mersini-Houghton.‘And that’s a big deal.’
A great article from www.pakalertpress.comIsn’t it obvious that there is a significant global awakening happening? Just as the Mayans predicted so many years ago, the apocalypse would become apparent in 2012. But many misinterpret the apocalypse to be the end of the world, when in fact it actually means an “un-covering, a revelation of something hidden.”As many continue to argue the accuracy of the Mayan calendar, it can no longer be argued that a great many people are finally [...]
New reports of further evidence for dark matter have been greatly exaggerated. Yesterday, researchers working with the Alpha Magnetic Spectrometer (AMS), a $2 billion cosmic ray detector attached to the International Space Station, reported their latest data on a supposed excess of high-energy positrons from space. They contended—at least in a press release—that the new results could offer new hints that they’ve detected particles of dark matter, the mysterious stuff whose gravity binds the galaxies. But several cosmic ray physicists say that the AMS data are still perfectly consistent with much more mundane explanations of the excess. And they doubt AMS alone will resolve the issue.
The leader of the AMS team, Nobel laureate Samuel Ting of the Massachusetts Institute of Technology in Cambridge, takes care to say that the new results do not prove that AMS has detected dark matter. But he also says the data lend more support to that interpretation than to some others. "The key statement is that we have not found a contradiction with the dark matter explanation," he says.
The controversy centers on AMS's measurement of a key ratio, the number of antimatter positrons to the sum of positrons and electrons. In April 2013, AMS confirmed early reports that as the energy of the particles increased above about 8 gigaelectron Volts (GeV), that ratio, or "positron fraction," increased, even as the individual fluxes of electrons and positrons were falling. That increase in the relative abundance of positrons could signal the presence of dark matter particles. According to many theories, if those particles collide, they would annihilate each other to produce electron-positron pairs. That would alter the balance of electrons and positrons among cosmic rays, as the usual source such as the cloudlike remnants of supernova explosions produce far more electrons than positrons.
However, that interpretation was hardly certain. Even before AMS released its measurement of the ratio, astrophysicists had argued that the excess positrons could potentially emanate from an undetected nearby pulsar. In November 2013, Eli Waxman, a theoretical astrophysicist at the Weizmann Institute of Science in Rehovot, Israel, and colleagues went even further. They argued that the excess positrons could come simply from the interactions of "primary" cosmic rays from supernova remnants with the interstellar medium. If so, then the positrons were just "secondary" rays and nothing to write home about.
However, AMS team researchers see two new features that are consistent with the dark matter interpretation, they reported online yesterday in Physical Review Letters. First, the AMS team now sees that after rising with energy, the positron fraction seems to level off and may begin to fall at an energy of 275 GeV, as would be expected if the excess were produced by colliding dark matter particles, as the original particles' mass would put an upper limit on the energy of the positron they spawned. AMS researchers say the leveling off would be consistent with a dark matter particle with a mass of 1 teraelectron volt (TeV). (Thanks to Albert Einstein’s famous equivalence of mass and energy, the two can be measured in the same units.)
Second, the AMS team measured the spectra of electrons and positrons individually. They found that the spectra have different shapes as energy increases. "It's really surprising that the electrons and positrons are so different," Ting says. And, he argues, the difference suggests that the positrons cannot be secondary cosmic rays produced by primary cosmic ray electrons, as such production should lead to similar spectra.
But some cosmic ray physicists aren't convinced. For example, in AMS's graph of the electron fraction, the error bars at the highest energies are large because the high-energy particles are so rare. And those uncertainties make it unclear whether the positron fraction really starts to drop, says Stéphane Coutu, a cosmic ray physicist at Pennsylvania State University, University Park. And even if the positron fraction does fall at energies higher than AMS reported, that wouldn't prove the positrons come from dark matter annihilations, Coutu says. Such a "cutoff" could easily arise in positrons from a pulsar, he says, if the spatial region in which the pulsar accelerates particles is of limited size. All told, the new results are "probably consistent with anything," Coutu says.
Similarly, Waxman questions Ting's claim that the new data suggest the positrons aren't simply secondary cosmic rays. If that were the case, then the electrons and positrons would be coming from different places and there would be no reason to expect their spectra to be similar, Waxman says. Moreover, he notes, AMS's measurement of the positron fraction seems to level out just at the limit that he and colleagues predicted would be the maximum achievable through secondary cosmic rays. So, in fact, the new data support the interpretation that the positrons are simply secondary cosmic rays, he says. "To me this is a very strong indication that we are seeing cosmic ray interactions.”
Will the argument ever end? AMS is scheduled to take data for 10 more years, which should enable scientists to whittle down the uncertainties and extend their reach toward higher energies, Ting says. "I think we should be able to reach 1 TeV with good statistics," he says, and that should be enough to eventually settle the dispute. But Gregory Tarlé, an astrophysicist at the University of Michigan, Ann Arbor, says, "I don't think that's a legitimate claim." Higher energy cosmic rays arrive at such a low rate that even quadrupling the data set would leave large statistical uncertainties, he says. So, Tarlé suspects, years from now the AMS results will likely look about as ambiguous they do now.
The leader of the AMS team, Nobel laureate Samuel Ting of the Massachusetts Institute of Technology in Cambridge, takes care to say that the new results do not prove that AMS has detected dark matter. But he also says the data lend more support to that interpretation than to some others. "The key statement is that we have not found a contradiction with the dark matter explanation," he says.
The controversy centers on AMS's measurement of a key ratio, the number of antimatter positrons to the sum of positrons and electrons. In April 2013, AMS confirmed early reports that as the energy of the particles increased above about 8 gigaelectron Volts (GeV), that ratio, or "positron fraction," increased, even as the individual fluxes of electrons and positrons were falling. That increase in the relative abundance of positrons could signal the presence of dark matter particles. According to many theories, if those particles collide, they would annihilate each other to produce electron-positron pairs. That would alter the balance of electrons and positrons among cosmic rays, as the usual source such as the cloudlike remnants of supernova explosions produce far more electrons than positrons.
However, that interpretation was hardly certain. Even before AMS released its measurement of the ratio, astrophysicists had argued that the excess positrons could potentially emanate from an undetected nearby pulsar. In November 2013, Eli Waxman, a theoretical astrophysicist at the Weizmann Institute of Science in Rehovot, Israel, and colleagues went even further. They argued that the excess positrons could come simply from the interactions of "primary" cosmic rays from supernova remnants with the interstellar medium. If so, then the positrons were just "secondary" rays and nothing to write home about.
However, AMS team researchers see two new features that are consistent with the dark matter interpretation, they reported online yesterday in Physical Review Letters. First, the AMS team now sees that after rising with energy, the positron fraction seems to level off and may begin to fall at an energy of 275 GeV, as would be expected if the excess were produced by colliding dark matter particles, as the original particles' mass would put an upper limit on the energy of the positron they spawned. AMS researchers say the leveling off would be consistent with a dark matter particle with a mass of 1 teraelectron volt (TeV). (Thanks to Albert Einstein’s famous equivalence of mass and energy, the two can be measured in the same units.)
Second, the AMS team measured the spectra of electrons and positrons individually. They found that the spectra have different shapes as energy increases. "It's really surprising that the electrons and positrons are so different," Ting says. And, he argues, the difference suggests that the positrons cannot be secondary cosmic rays produced by primary cosmic ray electrons, as such production should lead to similar spectra.
But some cosmic ray physicists aren't convinced. For example, in AMS's graph of the electron fraction, the error bars at the highest energies are large because the high-energy particles are so rare. And those uncertainties make it unclear whether the positron fraction really starts to drop, says Stéphane Coutu, a cosmic ray physicist at Pennsylvania State University, University Park. And even if the positron fraction does fall at energies higher than AMS reported, that wouldn't prove the positrons come from dark matter annihilations, Coutu says. Such a "cutoff" could easily arise in positrons from a pulsar, he says, if the spatial region in which the pulsar accelerates particles is of limited size. All told, the new results are "probably consistent with anything," Coutu says.
Similarly, Waxman questions Ting's claim that the new data suggest the positrons aren't simply secondary cosmic rays. If that were the case, then the electrons and positrons would be coming from different places and there would be no reason to expect their spectra to be similar, Waxman says. Moreover, he notes, AMS's measurement of the positron fraction seems to level out just at the limit that he and colleagues predicted would be the maximum achievable through secondary cosmic rays. So, in fact, the new data support the interpretation that the positrons are simply secondary cosmic rays, he says. "To me this is a very strong indication that we are seeing cosmic ray interactions.”
Will the argument ever end? AMS is scheduled to take data for 10 more years, which should enable scientists to whittle down the uncertainties and extend their reach toward higher energies, Ting says. "I think we should be able to reach 1 TeV with good statistics," he says, and that should be enough to eventually settle the dispute. But Gregory Tarlé, an astrophysicist at the University of Michigan, Ann Arbor, says, "I don't think that's a legitimate claim." Higher energy cosmic rays arrive at such a low rate that even quadrupling the data set would leave large statistical uncertainties, he says. So, Tarlé suspects, years from now the AMS results will likely look about as ambiguous they do now.
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| This artist's conception shows a newfound object named WISE J085510.83-071442.5, the coldest known brown dwarf. |
At the Las Campanas Observatory in Chile, Faherty, along with a team including Carnegie's Andrew Monson, used the FourStar near infrared camera to detect the coldest brown dwarf ever characterized. Their findings are the result of 151 images taken over three nights and combined. The object, named WISE J085510.83-071442.5, or W0855, was first seen by NASA's Wide-Field Infrared Explorer mission and published earlier this year. But it was not known if it could be detected by Earth-based facilities.
"This was a battle at the telescope to get the detection," said Faherty.
Chris Tinney, an Astronomer at the Australian Centre for Astrobiology, UNSW Australia and co-author on the result stated: "This is a great result. This object is so faint and it’s exciting to be the first people to detect it with a telescope on the ground."
Brown dwarfs aren't quite very small stars, but they aren't quite giant planets either. They are too small to sustain the hydrogen fusion process that fuels stars. Their temperatures can range from nearly as hot as a star to as cool as a planet, and their masses also range between star-like and giant planet-like. They are of particular interest to scientists because they offer clues to star-formation processes. They also overlap with the temperatures of planets, but are much easier to study since they are commonly found in isolation.
W0855 is the fourth-closest system to our own Sun, practically a next-door neighbor in astronomical distances. A comparison of the team's near-infrared images of W0855 with models for predicting the atmospheric content of brown dwarfs showed evidence of frozen clouds of sulfide and water.
"Ice clouds are predicted to be very important in the atmospheres of planets beyond our Solar System, but they've never been observed outside of it before now," Faherty said.
The paper's other co-author is Andrew Skemer of the University of Arizona.
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This work was supported by the Australian Research Council. It made use of data from the NASA WISE mission, which was a joint project of the University of California Los Angeles and the Jet Propulsion Laboratory and Caltech, funded by NASA. It also made use of the NASA/IPAC Infrared Science Archive, which is operated by the Jet Propulsion Laboratory and Caltech, under contract with NASA.
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