Milky Way Might Have Formed From Inside-Out

Posted January 21st, 2014 at 9:28 pm (UTC+0)
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This artist's concept illustrates the new view of the Milky Way. Scientists have discovered that the Milky Way's elegant spiral structure is dominated by just two arms wrapping off the ends of a central bar of stars. Previously, our galaxy was thought to possess four major arms. (Image: NASA)

Artist’s concept illustrates new view of the Milky Way  (NASA)

The Milky Way Galaxy may have formed from the inside-out, according to data from the Gaia-ESO Survey.

Using data gathered by the ESO’s 8-meter Very Large Telescope (VLT), located in Chile’s Atacama desert, astronomers were able to make their findings by tracking and studying the amounts of elements, such as magnesium, within the chemical composition of stars and gases contained within the galaxy.

The astronomers made detailed observations of a number of different-aged stars, located in a variety of regions of the Milk Way to accurately determine their metallicity, which is the amount of chemical elements contained within a star other than the two basic chemicals—hydrogen and helium—that stars are made of.

Shortly after the Big Bang about 14 billion years ago, the universe was made up only of those two basic elements (H & He), but over time, the cosmic mix included more and more metallic contaminants.  As a result, the older stars have fewer of these contaminants, or less metallicity, while newer stars have more of these elements in their mix.

“The different chemical elements of which stars—and we—are made, are created at different rates,” said Gerry Gilmore, lead investigator on the Gaia-ESO Project.”Some in massive stars which live fast and die young, and others in sun-like stars with more sedate multi-billion-year lifetimes.”

ESO's Very Large Telescope Array on Cerro Paranal Mountain (ESO)

ESO’s Very Large Telescope Array on Cerro Paranal Mountain (ESO)

Astronomers refer to stars with a mass of at least eight times that of the sun as massive stars. These massive stars tend to have relatively short lives which end in core-collapse supernovae.

This type of event is triggered when the nuclear fusion processes of the star (how a star produces energy) suddenly causes its core to collapse against its own gravity, which can cause it to explode and die.

This core-collapse supernova event can form a neutron star, a black hole, or even kick-start the formation of new stars.

The astronomers said that as the massive stars die, they produce large amounts of magnesium.

The team said older stars that do exist inside the Solar Circle—the orbit our sun makes around the center of the Milky Way—usually have higher levels of magnesium, which suggests that part of our galaxy contained more stars with a relatively shorter life span.

Stars outside of the Solar Circle, located within the outer regions of the galaxy, are younger and tend to have very low levels of magnesium.

The research team said its discovery illustrates the differences in the evolution of stars in our galaxy. The stars that took less time to form are closer to the core of the Milky Way, while the stars with a much longer, more involved formation process, reside closer to the edge of the galactic disk of the Milky Way.

(University of Cambridge)

(University of Cambridge)

“We have been able to shed new light on the timescale of chemical enrichment across the Milky Way disc, showing that outer regions of the disc take a much longer time to form,” said Maria Bergemann from Cambridge’s Institute of Astronomy, who led the study. “This supports theoretical models for the formation of disc galaxies in the context of Cold Dark Matter cosmology, which predict that galaxy discs grow inside-out.”

The astronomical team’s findings were recently published online in the astronomical database ‘Astro-ph’, and have also been submitted to the journal Astronomy and Astrophysics for possible publication.

Sleeping Comet Chaser to Get Wake-Up Call

Posted January 17th, 2014 at 8:26 pm (UTC+0)
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Artist view of the Rosetta spacecraft. Rosetta’s lander, Philae, is attached and is shown in blue (© ESA/J. Huart)

Artist view of the Rosetta spacecraft. Rosetta’s lander, Philae, is attached and is shown in blue (© ESA/J. Huart)

The European Space Agency’s comet chasing Rosetta spacecraft is about to wake up from a 31-month nap, which was induced to conserve power after the vehicle ventured too far from the sun.

While ESA officials are confident Rosetta will respond when they try to rouse it this Monday, Jan. 20, they also realize anything could happen since the spacecraft is now in deep space some 807 million kilometers from Earth.

For the last 10 years, Rosetta has been traveling through the solar system for a rendezvous with comet 67P/Churyumov-Gerasimenko or 67P/CG.

The Rosetta spacecraft and mission were designed to perform a detailed investigation of a comet.

Rosetta was put into hibernation mode in 2011 when its trajectory to the comet took it so far from the sun that it was unable to use solar arrays to gather the energy needed to power it.

Artist’s impression of Rosetta’s lander Philae on the surface of comet 67P/Churyumov-Gerasimenko. (© ESA/ATG medialab)

Artist’s impression of Rosetta’s lander Philae on the surface of comet 67P/Churyumov-Gerasimenko. (© ESA/ATG medialab)

After Rosetta was powered down, only its computer and several heaters were left running.

Also, to stabilize the spacecraft for its long trip to the comet, the ESA put it into a once-a-minute spin.

Now, 31 months after being put into hibernation, Rosetta’s trajectory has brought it back to where it’s closer to the sun and can gather enough solar energy to reach full power again.

After putting the spacecraft through a number of wake-up maneuvers, mission controllers at ESA’s European Space Operations Center in Darmstadt, Germany, will transmit a signal to Rosetta to take it out of its stabilizing spin and orient it so that its solar arrays face the sun, allowing it to draw enough energy to power-up and continue its mission as planned.

ESA says the Rosetta mission will give scientists the opportunity to gain some insight into the creation of the solar system and its planets.

ESA Video:

“Comets are very interesting objects, said Mark McCaughrean, ESA’s senior scientific advisor for space science missions. “They are effectively time capsules; they’ve locked up material which is left over from the birth of our own solar system. So by going to a comet, examining it in detail, studying its materials, what it’s made of, we hope to learn a lot more about the origin of the solar system we live in today.”

By studying the water that is locked up in comet 67P/CG, Rosetta mission officials hope to learn more about where the Earth’s water came from.

Image of the asteroid Lutetia taken at Rosetta's closest approach.(© ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA)

Image of the asteroid Lutetia taken at Rosetta’s closest approach.(© ESA 2010 MPS for OSIRIS Team MPS/UPD/LAM/IAA/RSSD/INTA/UPM/DASP/IDA)

McCaughrean says that since the Earth was too warm to hold much water after it was born, our ocean water had to have been delivered later. Scientists suspect this was accomplished following collisions with millions of comets.

Another reason to go to and study 67P/CG in great detail, according to McCaughrean, is that comets also contain lots of organic molecules, things which are the building blocks of more complex molecules like DNA.

He and other scientists believe that it’s quite possible that comets not only delivered our water, but also the ingredients for life on Earth.

McCaughrean thinks 67P/CG will be a great target for study because, unlike many comets, its surface hasn’t been heated by the sun many times.

When a comet gets heated by the sun, “it gets processed. It gets kind of different on the surface to the way it is underneath,” he said.  He and his colleagues think Rosetta’s target comet will contain plenty of the primitive materials that it collected as the solar system was being formed.

On its way to rendezvous with the comet, Rosetta has made three fly-bys of Earth and one of Mars, while also encountering asteroids Steins and Lutetia along the way.

Once Rosetta reaches its destination, which should be in August, it will spend time orbiting the comet to gather crucial data. Then, in November, it will deploy the Philae lander, a small spacecraft on board, that will land on the comet itself. The Philae will use its 10 specialized instruments to sample and analyze material from the comet’s surface and subsurface.

The Rosetta Stone which is on display at the British Museum (Hans Hillewaert via Wikimedia/Creative Commons)

The Rosetta Stone which is on display at the British Museum (Hans Hillewaert via Wikimedia/Creative Commons)

The Rosetta mission, which was green-lighted in 1993, is named after the famous Rosetta stone. Engraved on this important historic object is a decree issued by a group of ancient Egyptian priests around the year 196 BC.

The stone was inscribed with essentially the same text in three languages – ancient Egyptian Demotic, Greek and Egyptian Hieroglyphs. Scientists, with the knowledge of Demotic and Greek, were able to decipher the meaning of modern Hieroglyphs.

Some consider the deciphering of the Rosetta Stone as the pioneering effort in translating unknown languages. ESA scientists are hoping their Rosetta spacecraft, like the object it was named after, will help unlock the mysteries of how the solar system evolved.

Mark McCaughrean joins us on this week’s radio edition of “Science World” to talk about the Rosetta mission and Jan. 20 wake up call. Tune in (see right column for scheduled times) or check out the interview in the player below.

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Have Researchers Debunked Idea of “Sixth Sense” ?

Posted January 15th, 2014 at 9:12 pm (UTC+0)
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Zener cards used in the early twentieth century for experimental research into ESP. (Wikimedia Commons)

Zener cards like those shown here were used in the early twentieth century for experimental research into ESP. (Wikimedia Commons)

There are people who claim to have a sixth sense or extrasensory perception (ESP), the ability to acquire or “see” information about the future through means other than normal human senses.

Researchers at the University of Melbourne have looked into the matter and say their findings help debunk the belief that a sixth sense actually exists.

The Aussie researchers outlined their research and findings in a study published recently in  PLOS ONE. Their findings show that while people could sense when a change took place, without the benefit of the other senses, they could not specifically identify that change.

They found that a person might be able to pick up a change in a person’s appearance, but not, for example, be able to precisely pinpoint that the exact change in appearance was something such as getting a new hairstyle or wearing jewelry.

“There is a common belief that observers can experience changes directly with their mind, without needing to rely on the traditional physical senses such as vision, hearing, taste, smell and touch to identify it,” said Piers Howe from the Melbourne School of Psychological Sciences.

This demonstrates how the researchers tested their volunteer observers (Piers D.L.Howe/Margaret E. Webb/PLOS ONE)

This demonstrates how the researchers tested their volunteer observers (Piers D.L.Howe/Margaret E. Webb/PLOS ONE)

Howe said the research conducted by his team showed that while people could consistently sense changes that they could not see, their ability to do so had nothing to do with a sixth sense or extrasensory perception.”

To reach their findings, the researchers gathered volunteer observers who were shown pairs of color photos of the same female. In some of the photos, the woman’s appearance could be different, such as a new hairstyle, from the other in the pair.

Each of the photos was shown to the observer for about 1.5 seconds and then a 1 second pause before showing the next photo. After looking at the second photo, the researchers asked the observer whether or not a change had taken place between the first and second picture. Then they were asked to specifically identify that change in appearance from a list of nine different changes.

The researchers found that their volunteer observers were able to pick-up on a change in appearance even when they couldn’t pinpoint what that specific change was.

While they might notice one of the two photos had more of one color than the other, they weren’t able to translate that information into specifics such as the change in color was due to the woman wearing different clothing.

This resulted in the observer “feeling” or “sensing” that a change had occurred without being able to visually identify the change. Thus, the result that observers can reliably feel or sense when a change has occurred without being able to visually identify the change could be explained without invoking an extrasensory mechanism.

So what do you think? Do you agree with the researchers that a “sixth sense” does not actually exist? Or do you think ESP is a legitimate phenomenon?

Caffeine Might Improve Long-term Memory

Posted January 13th, 2014 at 4:41 pm (UTC+0)
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A steaming hot cup of coffee provides drinkers with a quick dose of caffeine (Greenray studios/Alex Upshur via Wikimedia Commons)

A hot cup of coffee provides drinkers with a quick dose of caffeine. (Greenray studios/Alex Upshur via Wikimedia Commons)

Caffeine  not only gives us a daily jump start, but new research suggests it also can enhance long-term memory.

According to the US Food and Drug Administration, nearly 90 percent of people worldwide consume about 200 milligrams of caffeine each day.  That’s equivalent to about one strong cup of coffee a day. Writing in “Nature Neuroscience”, Johns Hopkins University researchers say  their findings show caffeine boosts certain memories for up to 24 hours after being ingested.

“We’ve always known that caffeine has cognitive-enhancing effects, but its particular effects on strengthening memories and making them resistant to forgetting has never been examined in detail in humans,” said senior author of the paper Michael Yassa, formerly of Johns Hopkins and now the University of California, Irvine. “We report for the first time a specific effect of caffeine on reducing forgetting over 24 hours.”

Conducting a double-blind trial, the researchers worked with a test group of people who didn’t regularly consume caffeinated products. Five minutes after studying a series of images, the test subjects were given either a placebo or a 200-milligram caffeine tablet.

To check the caffeine levels of their test subjects, the research team took saliva samples from them before they took their tablets and again one, three and 24 hours afterwards.

Both groups of test participants (those who took the placebo and those who took the caffeine tablet) were tested the following day to see if they recognized images they’d seen the previous day.

The test included showing the test subjects another series of images that included some new images, those that were shown the previous day, as well as other images that were similar, but not the same as those they had viewed earlier.

The researchers found that more members of the group who were given the caffeine tablets were able to correctly identify some of the new images as “similar” to previously viewed images rather than incorrectly identifying them as the same.

Video: Johns Hopkins University

Being able to recognize the difference between two similar but not exactly alike items is called pattern separation, which is something, according to the researchers, that reveals a greater level of memory retention.

Only a few studies on the effect of caffeine on long-term memory have been conducted previously, and those that had been done did not provide much detail, according to the researchers.  Those studies suggested caffeine had little or no effect on long-term memory retention.

The research team said its research was different from  prior studies because its test subjects took their caffeine tablets after looking at and trying to memorize the images they were shown.

“The next step for us is to figure out the brain mechanisms underlying this enhancement,” said Yassa. “We can use brain-imaging techniques to address these questions. We also know that caffeine is associated with healthy longevity and may have some protective effects from cognitive decline like Alzheimer’s disease. These are certainly important questions for the future.”

2014’s 1st Asteroid May Have Hit Earth

Posted January 3rd, 2014 at 7:42 pm (UTC+0)
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This animated GIF shows Asteroid 2014 AA, discovered by the NASA-sponsored Catalina Sky Survey on Jan. 1, 2014, as it moved across the sky. Image credit: CSS/LPL/UA

This animated GIF shows Asteroid 2014 AA, discovered by the NASA-sponsored Catalina Sky Survey on Jan. 1, 2014, as it moved across the sky. (CSS/LPL/UA)

As Americans were ringing in 2014 early Wednesday morning, scientists caught sight of what appeared to be a very small asteroid – between 2 and 3 meters in size – on a potential impact trajectory with Earth.

The observation was made at the Catalina Sky Survey near Tucson, Arizona. The space rock, designated 2014 AA, may have been the first asteroid discovery of the New Year. If the space object was an asteroid, scientists, using the scant observational data that was available to them, suggest that it probably entered Earth’s atmosphere sometime between 2 p.m. EST, Wednesday, Jan. 1 and 9 a.m. EST Thursday, Jan. 2.

Three independent projections of the space object’s possible orbit were made by Bill Gray, of the Minor Planet Center in Cambridge, Massachusetts, and Steve Chesley from NASA’s Near Earth Object Program at the Jet Propulsion Laboratory in Pasadena, California.  The two scientists agree that 2014 AA probably pushed its way into Earth’s atmosphere.

Using data produced by weak signals from three infrasound detections, the crisscrossing of the white lines in this image indicates a possible impact point of asteroid 2014 AA (Peter Brown/University of Western Ontario)

Using data produced by weak signals from three infrasound detections, the crisscrossing of the white lines in this image indicates possible impact points of asteroid 2014 AA (Peter Brown/University of Western Ontario)

Because of the uncertainty of the object’s orbit, 2014 AA could have fallen anywhere along an arc that extends from Central America to East Africa.

The scientists think that the object may have impacted Earth at 9 PM EST on Jan. 1, just off the coast of West Africa.

NASA said that since another asteroid, 2008 TC3, which was also between 2 to 3 meters in size, completely broke up in October 2008 as it passed over northern Sudan, it’s doubtful that asteroid 2014 AA would have made it through its rough atmospheric entry intact.

Asteroid 2008 TC3, according to NASA, was the only other example of an incoming celestial object that was discovered just prior to hitting Earth.

The scientists are continuing their research into the fate of 2014 AA.  They will be analyzing data generated by a few weak signals collected from infrasound – low frequency – monitoring stations located along the predicted impact arc to see if they could be connected to the atmospheric entry of 2014 AA.

Want to Quit Smoking? Seek Professional Help

Posted December 20th, 2013 at 7:31 pm (UTC+0)
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It can be tough for long time smokers to refuse a cigarette (U.S. Air Force via Wikimedia Commons)

(Photo: U.S. Air Force)

If your New Year’s resolution is to quit smoking, you might want to consider what scientists in England have learned.  According to their study published in  Addiction, smokers who want to kick the habit are better off seeking the help of a trained advisor, rather than doing it themselves.

The researchers found self-help aids such as nicotine patches, gum or other products, do not improve the chances of quitting smoking. They used data from the “Smoking Toolkit Study,” a large ongoing research project that’s been conducted since 2007. The UK project follows current smokers as well as those who recently quit smoking.

The researchers wanted to find out which smoking cessation methods were the most successful. So, they analyzed the responses to survey questions answered by more than 10,000 Britons who had tried to stop smoking over the prior year.

The results showed that smokers who use services provided by smoking cessation advisors, often offered by health care organizations, have the best chance of successfully kicking their smoking habit.

The study also points out that over-the-counter therapies, such as the nicotine patches and gum, alone might not be as beneficial as they may think.

Those who try to quit smoking using a combination of specialized behavioral support, along with anti-smoking medicine or nicotine replacement products, are three times more likely to be successful than those who try to stop smoking on their own.

Health experts say smoking can be hazardous to your health (CDC via Wikipedia Commons)

(Graphic: CDC via Wikipedia Commons)

In fact, the researchers found that smokers who only use over-the-counter smoking cessation aids, without the help of a trained advisors, have the same rate of success as those who didn’t use any of those quit-smoking products at all.

“When you think that stopping smoking saves six hours of life for every day of smoking avoided, investing an hour or two over a 6 week period to see…[a] stop smoking advisor seems like a good investment,” said Robert West from University College London, who led the team of researchers. “They can provide cheaper medicine than is available in shops and advise how to use it properly. It’s crazy that not all smokers who want to stop do it. As far as nicotine products bought from shops are concerned, there is an urgent need to understand what is going on because we know that if these products are used properly, they can be effective.”

Move Over Cleopatra, Chinese May Have Loved Cats Before Ancient Eyptians

Posted December 18th, 2013 at 5:17 pm (UTC+0)
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Humans and cats have long enjoyed a close relationshipe with each other (Bill Abbott via Flickr/Creative Commons)

(Bill Abbott via Flickr/Creative Commons)

Researchers in China and Missouri have traced the origins of today’s domesticated cat back 5,300 years to an ancient Neolithic Chinese agricultural village located in the modern-day Shaanxi Province.

Like in the old Mother Goose nursery tale “This is the cat that killed the rat that ate the malt that lay in the house that Jack built,” the cats that would later become popular household pets were attracted to village farms because of the number of small animals, like rodents, that feasted on the grains grown, stored and eaten by the ancient Chinese farmers.

“Results of this study show that the village of Quanhucun was a source of food for the cats 5,300 years ago, and the relationship between humans and cats was commensal, or advantageous for the cats,” said the study’s co-author Fiona Marshall, a professor of archaeology at Washington University in St. Louis. “Even if these cats were not yet domesticated, our evidence confirms that they lived in close proximity to farmers, and that the relationship had mutual benefits.”

Ancient Egyptians worshiped the goddess Bastet. Considered to be a protector deity she was represented as a cat. (Gunkarta via Wikipedia Commons)

Ancient Egyptians worshiped the goddess Bastet. Considered to be a protector deity she was represented as a cat. (Gunkarta via Wikipedia Commons)

There are believed to be about 600 million domesticated cats in the world. Scientists who’ve conducted DNA studies believe most felines descended directly from the Near Eastern Wildcat, one of the five Felis sylvestris lybica or African wildcat subspecies still found in Africa, Asia and Europe.

“We do not yet know whether these cats came to China from the Near East, whether they interbred with Chinese wild-cat species, or even whether cats from China played a previously unsuspected role in domestication,” Marshall said.

Scientists have long thought cats were first domesticated in ancient Egypt, where they were revered more than 4,000 years ago.

New research, however, indicates the close relationship between cats and humans may have taken root much earlier.

In 2004, scientists discovered a wild cat had been  buried with a human nearly 9,500 years ago in Cyprus.

The researchers who conducted this new study, which is published in  Proceedings of the National Academy of Sciences, used various scientific techniques, such as radiocarbon dating and isotopic analyses of carbon and nitrogen traces on the bones of cats, dogs, deer and other forms of wildlife that they dug up near Quanhucan Village.

The clues researchers gathered suggest cats and humans were developing a closer relationship with each other at that time thousands of years ago.

The Near Eastern Wildcat, native to Western Asia and Africa, is believed to be the primary ancestor of all domestic cats now living around the globe. (Wikipedia Commons)

The Near Eastern Wildcat, native to Western Asia and Africa, is believed to be the primary ancestor of all domestic cats now living around the globe. (Wikipedia Commons)

One of the cats  found during their archeological dig was old when it died, which indicated that it lived well and flourished while living in the village.

The researchers also said that the remains of the ancient cats they studied showed signs that they didn’t eat too many animals and ate more millet than was expected. This suggested to the researchers that the cats either scavenged for human food or were fed by their human neighbors.

Other researchers working in China and in France are currently continuing the investigation of the domestication of cats and the development of the feline/human relationship.

Data Shows Universe Could Collapse Any Minute

Posted December 16th, 2013 at 7:08 pm (UTC+0)
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The European Space Agency's Planck mission released what they called the best map ever of the universe. (Image: ESA and the Planck Collaboration)

The European Space Agency’s ‘best map ever of the universe’. (Image: ESA and the Planck Collaboration)

Our universe is at even greater risk of collapse than has been previously thought, according physicists in Denmark.

Not only are the scientists predicting the end of the world… but the end of the universe!

The prediction that the universe will collapse and compress into a small hard ball isn’t something new. Physicists have been predicting a calamity for a long time.

Does this mean we should immediately cancel any long-term plans? The Danish scientists really don’t know when the universe will collapse. They say it could happen tomorrow–or  a billion years from now.

Writing in the Journal of High Energy Physics, the University of Southern Denmark physicists said new calculations led them to speculate  there will be a sudden and drastic change within the forces of the universe one day  that will make every atom in the universe become enormously heavy.

Everything, from the tiniest grain of soil to all of the planets within our solar system to every galaxy contained within the universe, will suddenly become billions and billions of times heavier than they are now.

The Big Bang theory says the universe expanded from an extremely dense and hot state (bottom) and continues to expand today (top)  (Wikimedia Commons)

The Big Bang theory says the universe expanded from an extremely dense and hot state (bottom) and continues to expand today (top). (Wikimedia Commons)

The theory holds that the sudden increase in weight will force all of the material within the universe to compress into a “small, super-hot heavy ball” which will cause the end of the universe as we know it.

The physicists call this powerful and destructive process “phase transition,” and they compare it to what happens when water boils and becomes steam, or when a magnet, after heating up, loses its magnetization.

This phase transition within the universe would take place if a bubble is formed where a Higgs-field, that’s related to the Higgs-Boson, transforms into a different value than the rest of the universe.

If this newly formed bubble is big enough, and the newly modified value produces lower energy, the bubble will then grow and expand in all directions at a pace the speed of light.

This rapid expansion of the bubble will cause all of the fundamental particles within the bubble to reach a mass that is a lot heavier than if they were located outside the bubble.

This increase of mass inside the bubble then will pull together and form what the physicists described as “supermassive centers”.

In a simulated data model, a Higgs boson is produced which decays into two jets of hadrons and two electrons. (Photo: CERN)

In a simulated data model, a Higgs boson is produced which decays into two jets of hadrons and two electrons. (Photo: CERN)

“Many theories and calculations predict such a phase transition, but there have been some uncertainties in the previous calculations,” said Jens Frederik Colding Krog of the University of Southern Denmark, who co-authored the paper. “Now we have performed more precise calculations, and we see two things: Yes, the universe will probably collapse, and: A collapse is even more likely than the old calculations predicted. “

He said this phase transition could start at any spot in the universe and then spread out to the entire universe.

“Maybe the collapse has already started somewhere in the universe and right now it is eating its way into the rest of the universe,” Krog said. “Or maybe it will start far away from here in a billion years. We do not know.”

Along with “phase transition,” another theory,  “The Big Crunch Theory,” could also spell the end of our universe.  “The Big Crunch” is based on and is the opposite of the “Big Bang” theory in creating the universe.

Following that Big Bang 13.7 billion years ago, material that made up galaxies, stars, and planets was expelled into a continually expanding universe from one small region.

Animated illustration demonstrates the "Big Crunch Theory" (Wikimedia Commons)

Animated illustration demonstrates the “Big Crunch Theory” (Wikimedia Commons)

According to the “Big Crunch”, there will be a point and time when this expansion will cease and  all of that material will attract each other and ultimately come together again in a small area.

“The latest research shows that the universe’s expansion is accelerating, so there is no reason to expect a collapse from cosmological observations,” Krog said. “Thus it will probably not be Big Crunch that causes the universe to collapse. “The Danish physicists said that while their new calculations predict the collapse of the universe is now more likely than ever, they also said it’s possible  it won’t happen at all.

A requirement for the phase change to take place, according to the researchers, is that the universe contains all of the known fundamental particles, including the Higgs boson. But, if the universe also contains undiscovered particles, the entire idea for predicting the phase change vanishes.

“Then the collapse will be canceled,” said Krog.

Curiosity Determines Age of Martian Rocks

Posted December 13th, 2013 at 7:33 pm (UTC+0)
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This sequence of images from Curiosity's Front Hazard-Avoidance Camera shows the rover drilling into a rock target (NASA/JPL-Caltech)

This sequence of images from Curiosity’ show the rover drilling into a rock target. (NASA)

The Curiosity Rover has accomplished yet another first as it continues its amazing journey across the Martian landscape.

Scientists from the California Institute of Technology (Caltech) have been able to successfully determine the age of a Martian rock.

But what makes this finding special is that, for the first time, scientists have been able to do so on Mars itself, using some of the science tools built into the Mars Science Laboratory (MSL).

The team’s long-distance analysis has determined that the rocks they examined were about 3.86 to 4.56 billion years old.

The Caltech team got the go ahead to conduct its research after submitting a proposal to officials leading the Mars Science Laboratory (MSL) mission.  To determine the age of rocks on Mars, they proposed using research techniques similar to those used by scientists who’ve done the same thing with alien rocks found here on Earth.

Back in March, while exploring the Yellowknife Bay area of Mars’ Gale Crater, the Curiosity rover used a drill mounted on its robotic arm to bore a couple of holes into fine-grained sedimentary rock, called mudstone.

A mosaic of images from Curiosity's Mast Camera (Mastcam) shows geological members of the Yellowknife Bay formation, and the sites where Curiosity drilled into Martian mudstone. (NASA/JPL-Caltech/MSSS)

A mosaic of images from Curiosity’s Mast Camera (Mastcam) shows geological members of the Yellowknife Bay formation, and the sites where Curiosity drilled into Martian mudstone. (NASA)

Scientists said that these rocks were deposited in the bed of what they think is an ancient lake that may have flowed on Mars 3.6 million years ago.

Next, the rover scooped up the powdered rock that was produced by drilling into the rocks.The Sample Analysis on Mars instrument (SAM), which is installed aboard the Curiosity, conducted a number of chemical analyses on the powered rock samples, including several geochronology or rock-dating techniques.

Farley and his colleagues say there might be a bit of uncertainty regarding their measurements because the sedimentary rocks they studied were created in layers, over millions of years, with materials that had eroded from the local surroundings. The researchers presume the age of the samples they analyzed is actually a combined age of the different particles that the rocks were made of.

The Curiosity rover left the Yellowknife Bay research area and is moving on to new places to drill for rock samples as it makes its way to its eventual destination on Mount Sharp. The new drill sites will provide even more opportunities for scientists to analyze and date Martian rocks.

View into one of the drillholes in Martian mudstone made by Curiosity in the Yellowknife Bay area of Gale Crater. A sample of powdered material from the rock was used to determine the age of the rocks. (NASA/JPL-Caltech/MSSS)

A drill hole in the Martian mudstone made by Curiosity. A sample of powdered material from the rock was used to determine the age of the rocks. (NASA)

Caltech geochemist Ken Farley, who led the research, said that he and his colleagues will probably have Curiosity drill into more Martian rocks sometime in January to further test their rock dating techniques.

A paper that outlines the work done by the Caltech team has been published in the journal Science Express.

The team said its recent findings might not only help scientists better understand the geologic history of the red planet, but could also help support the MSL’s mission team in its search for evidence of ancient life on Mars.

Scientists Find the Coldest Place on Earth

Posted December 11th, 2013 at 7:53 pm (UTC+0)
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This image shows the location of record low temperature measurements for Antarctica. (Ted Scambos, National Snow and Ice Data Center) The red dots show where the record satellite-measured surface temperatures and the earlier record low air temperature occurred. Shades of gray are a compilation of the lowest MODIS-sensor land surface temperature readings made by NASA's Aqua satellite during 2003-2013, with darker grays representing the coldest areas. Landsat 8 thermal images acquired in July and August of 2013 provided more detail on the coldest areas (purple squares). Elevation of the Antarctic surface is shown in green lines, and a blue lines provide an outline of the Antarctic continent, its islands, and the edge of its floating ice sheet.

This image shows the location of record low temperature measurements for Antarctica. (Ted Scambos, National Snow and Ice Data Center)

Winter officially arrives in the Northern Hemisphere in about 10 days (12/21/13).  Here in the Washington, DC area, temperatures have already been dropping below 0° C at times.

While some of us are already complaining about the recent icy temperatures we know it could be a lot worse!

Scientists from NASA and the U.S. Geological Survey (USGS), using a variety of sophisticated devices, such as those on the Landsat 8 satellite launched earlier this year (see related story), have found the coldest place on Earth.

Temperatures at spots along a 1,000 km strip of a remote and desolate ice plateau in East Antarctica have been measured between −92° to −93.2° C.

Project researchers made the temperature measurements between 2003 and 2013.

They used the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor, an instrument installed on NASA’s Terra and Aqua satellites as well as the Advanced Very High Resolution Radiometer (AVHRR) which is aboard several National Oceanic and Atmospheric Administration satellites.

NASA Video – The Coldest Place in the World (NASA)

During the 2013 Southern Hemisphere winter (6/21/13 – 9/23/13) their temperature measurements were augmented with data that was taken by equipment aboard the new Landsat 8 Earth observing satellite.

The newly recorded coldest temperature of -93.2° C was set on August 10, 2010 and it beats a record from more than 30 years ago when it was −89.2° C on July 21, 1983 at the Vostok Research Station in East Antarctica.

Ted Scambos the lead scientist at the National Snow and Ice Data Center (NSIDC) at the University of Colorado Boulder also joined the NASA/USGS team for this project. “I’ve never been in conditions that cold and I hope I never am,” said Scambos. “I am told that every breath is painful and you have to be extremely careful not to freeze part of your throat or lungs when inhaling.”

An Atlas-V rocket with the Landsat Data Continuity Mission (LDCM) spacecraft onboard is seen as it launches on Monday, Feb. 11, 2013 at Vandenberg Air Force Base, Calif. (Photo: NASA/Bill Ingalls)

An Atlas-V rocket with the Landsat Data Continuity Mission (LDCM) spacecraft onboard is seen as it launches on Monday, Feb. 11, 2013 at Vandenberg Air Force Base, Calif. (Photo: NASA/Bill Ingalls)

These record temperatures in East Antarctica are much colder than a few other areas where sub-freezing temperatures are normal.

The project scientists found that the lowest recorded temperature in the United States was in Alaska coming in at −62° C.  In northern Asia cold temperatures have dipped to -68° C, while a temperature of -75° C was measured at the peak of the Greenland Ice Sheet.

According to NASA the coldest permanently inhabited place on Earth is located in northeastern Siberia, where temperatures dropped to -67.8° in the towns of Verkhoyansk – 1802 and Oymyakon – 1933.

The new record cold temperatures were found by the scientists in several 5 by 10 km pockets where the topography of the area shapes shallow hollows of about 2 to 4 meters deep.

These small dips in Antarctic landscape are close to an ice ridge that runs between the ice-dome peaks of Dome A (Argus) and Dome F (Fuji) which are located on the East Antarctic Ice Sheet.  An ice-dome has been described as a mass of ice located on an ice-sheet that has been shaped into a dome.

The researchers say that the cold air begins near the snow surface. Since cold air is thought to be much denser that the air above, this already cold air then moves down into those hollows making the air even colder, under ideal conditions.

“The record-breaking conditions seem to happen when a wind pattern or an atmospheric pressure gradient tries to move the air back uphill, pushing against the air that was sliding down,” Scambos said. “This allows the air in the low hollows to remain there longer and cool even further under the clear, extremely dry sky conditions. When the cold air lingers in these pockets it reaches ultra-low temperatures,” he added.

The researchers happened to notice the record low temperatures while they were studying some unusual cracks on East Antarctica’s ice surface that could be several hundred years old.

Satellite image shows a portion of the East Antarctic Ice Sheet (NASA)

Satellite image shows a portion of the East Antarctic Ice Sheet (NASA)

The scientists say that they suspect that a layer in the atmosphere above the ice plateau reaches a certain minimum temperature and is preventing the ice plateau’s surface from getting any colder.

“There seems to be a physical limit to how cold it can get in this high plateau area and how much heat can escape,” Scambos said. “The levels of carbon dioxide, nitrogen oxide, traces of water vapor and other gases in the air may impose a more or less uniform limit on how much heat can radiate from the surface.”

The researchers say that they will continue to refine their map of Earth’s coldest places using Landsat 8 data.

“It’s a remarkable satellite and we’ve repeatedly been impressed with how well it works, not just for mapping temperature but for mapping crops and forests and glaciers all over the world,” Scambos said.

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