Hubble Helps Astronomers Solve 40 Year-Old Mystery

Posted August 9th, 2013 at 10:52 pm (UTC+0)
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Radio/visible light all-sky View of the Magellanic Stream  (NASA)

Radio/visible light all-sky View of the Magellanic Stream (NASA)

Astronomers finally have been able to solve a 40-year mystery thanks to the Hubble Space Telescope.

For over four decades astronomers have been trying to find the origin of the Magellanic Stream, a long ribbon of hydrogen gas clouds that stretch almost halfway around our own Milky Way galaxy.

The Magellanic Stream is connected to the Large and Small Magellanic Clouds, which are two small and irregular galaxies that are orbiting the Milky Way.

These irregular galaxies – those that do not have a distinctive regular shape – are among the Milky Way’s closest galactic neighbors and have long provided stargazers with spectacular astronomical images, even more so since advanced telescopes like the Hubble went online.

The Magellanic Stream was discovered with radio telescopes in the early 1970’s and since then astronomers have wanted to know whether the stream’s origination came from one or both of the clouds.

Close-up radio map of the Magellanic Stream  (Leiden-Argentine-Bonn (LAB) Survey)

Close-up radio map of the Magellanic Stream (Leiden-Argentine-Bonn (LAB) Survey)

Using recent Hubble observations, two teams of astronomers found that most of the stream’s gas pulled away from the Small Magellanic Cloud about 2 billion years ago. They also found that a second region of the stream was created a little more recently from the Large Magellanic Cloud.

The astronomers, led by Andrew J. Fox of the Space Telescope Science Institute in Maryland, were able to make their findings with the Hubble’s Cosmic Origins Spectrograph.

This device aboard the space telescope allowed them to determine the amount of heavy elements – anything heavier than helium – such as oxygen and sulfur at several areas alongside the Magellanic Stream. They were able to detect those heavy elements by observing the way they absorbed ultraviolet light.

The Hubble in orbit above the Earth (Photo: NASA)

The Hubble in orbit above the Earth (Photo: NASA)

One team said that they found a small amount of oxygen and sulfur along most of the stream, which matched the levels of the elements that was in the Small Magellanic Cloud when the stream first formed. The team was surprised to discover a much higher level of sulfur in an area of the stream that’s closer to the Magellanic Clouds.

“We’re finding a consistent amount of heavy elements in the stream until we get very close to the Magellanic Clouds and then the heavy element levels go up,” said Fox. “This inner region is very similar in composition to the Large Magellanic Cloud, suggesting it was ripped out of that galaxy more recently.”

Fox went on to explain that the only way his team was able to measure the quantities of the heavy elements in the stream was by using the ultraviolet observational method.  This is something he said could only be done with space telescopes like the Hubble, but not earth based telescopes since our atmosphere tends to absorb ultraviolet light.

The Large Cloud of Magellan (Credit & Copyright: Wei-Hao Wang (IfA, U. Hawaii))

The Large Cloud of Magellan (Credit & Copyright: Wei-Hao Wang (IfA, U. Hawaii))

Compared to other satellite galaxies of the Milky Way, the researchers pointed out that so far, both Magellanic Clouds have been able to hold on to their supplies of gas and are still able to create new stars because they’re more massive than others.

But that is something that they say probably won’t last forever since the Magellanic Clouds are getting closer to our own galaxy and are feeling, more and more, the gravitational effects of their much larger neighbor.

This growing gravitational pull is forcing each of the two clouds to smash into halos of gas that surround them, which in turn are pushing their own supplies of gas out. All of that along with a “gravitational tug-of-war” between the Magellanic Clouds themselves is leading to the production of a gas stream.

The researchers say that eventually the gassy stream being produced by the two satellite galaxies may pour onto the Milky Way’s stellar disk, which will fuel the creation of new stars. This mix of fresh gas is part of a process that produces star formation in a galaxy. Astronomers wanted to know the origin of that wayward gas so that they could better understand how galaxies make new stars.

The Small Cloud of Magellan (Credit & Copyright: Josch Hambsch, Robert Gendler)

The Small Cloud of Magellan (Credit & Copyright: Josch Hambsch, Robert Gendler)

“We want to understand how galaxies like the Milky Way strip the gas from small galaxies that fall into them and then use it to form new stars,” said Fox. “This seems like it’s an episodic process. It’s not a smooth process where a slow stream of gas comes in continuously. Instead, once in a while a large gas cloud falls in. We have a way of testing that here, where two galaxies are coming in. We’ve shown which of them is producing the gas that ultimately will fall into the Milky Way.”

The research and findings made by the astronomers in this investigation were outlined in two papers that were published in a recent issue of the “Astrophysical Journal.”  Fox was the lead author of one paper, while Philipp Richter of Germany’s University of Potsdam served as the lead author of the second paper.

Chocolate Could Be the Latest ‘Brain’ Food

Posted August 7th, 2013 at 8:00 pm (UTC+0)
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Enjoying a nice hot cup of cocoa (Orin Zebest via Creative Commons @ Flickr)

(Orin Zebest via Creative Commons @ Flickr)

Chocoholics have a new reason to enjoy their favorite treat free of guilt.  New research suggests chocolate is good for keeping your brain healthy and functioning sharply, perhaps delaying or slowing diseases such as Alzheimer’s.

A Harvard researcher found that drinking  two cups of hot chocolate a day helps older people keep their brains healthy and their thinking abilities strong.

“We’re learning more about blood flow in the brain and its effect on thinking skills,” said Farzaneh A. Sorond, of the Harvard Medical School and a Boston area neurologist. “As different areas of the brain need more energy to complete their tasks, they also need greater blood flow. This relationship, called neurovascular coupling, may play an important role in diseases such as Alzheimer’s.”

Sorond studied 60 people who were, on average, 73 years old, and didn’t have any form of dementia.

Over a 30-day period, Sorond had his volunteers drink two cups of hot cocoa a day while abstaining from consuming any other forms of chocolate during that time.

The study participants didn’t drink the same cocoa. Half  consumed hot cocoa  enhanced with an additional amount of the antioxidant flavanol, which is normally found in cocoa as well as tea and some fruits and vegetables.  The  other half received cocoa with a much smaller amount of the added antioxidant.

Sorond found that the amount of flavanol enhancement made no difference between the two groups of people, but drinking hot chocolate did seem to have an impact.

A delicious cup of hot chocolate (Paul Wilkinson via Wikimedia Commons at Flickr)

(Paul Wilkinson via Wikimedia Commons at Flickr)

Throughout the 30-day period, the study participants took memory and thinking skills tests as well as ultrasound tests to measure the amount of blood flow to the brain.

Eighteen participants showed signs of having impaired blood flow to their brains at the start of the study. By the end of the 30-day test period, those 18 people showed an 8.3-percent improvement in the blood flow to the working areas of their brain. They also improved their performance on a  working memory test, with scores dropping from 167 seconds at the beginning of the study to 116 seconds at the end.

However, study participants who started the tests with normal brain blood flow showed no improvement.

Twenty-four of the research participants – a mix of those with and without the restricted brain blood flow – were given MRI scans of their brains to see if there were any tiny areas of brain damage.

The MRI scans revealed that those with reduced blood flow were also more likely to have these small areas of brain damage.

“More work is needed to prove a link between cocoa, blood flow problems and cognitive decline,” said Paul B. Rosenberg of Johns Hopkins School of Medicine in Baltimore, who wrote an editorial that accompanied the study. “But this is an important first step that could guide future studies.”

Warmer Climate Linked to Increased Human Violence

Posted August 2nd, 2013 at 7:45 pm (UTC+0)
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As global temperatures rise, so do our levels of hostility and violence, according to a new study.

Scientists from the University of California, Berkeley and Princeton University  discovered a strong link between shifts in climate to human violence around the world.  The study found that even minor climate deviations, such as slight changes in normal temperature and rainfall, can greatly increase the risk of conflict.

The link between climate variations and violent behavior was noted on a small scale—in one-on-one crimes like assault, murder or domestic abuse—as well as on a much grander scale involving riots or civil war.

Unlike previous similar studies, this project combined data and evidence from a wider number of fields such as economics, political science, geography, psychology and archeology, according to Professor Edward Miguel from the University of California Berkeley.

Climate shifts researchers explored included temperature as well as rainfall—from very low rainfall and drought conditions to extreme amounts of rainfall.

El Castillo, also known as the Temple of Kukulkan - This is a Mesoamerican step-pyramid built by the pre-Columbian Maya civilization sometime between the 9th and 12th centuries in what is now the Mexican state of Yucatá (Daniel Schwen via Wikimedia Commons)

This is a Mesoamerican step-pyramid built by the pre-Columbian Maya civilization sometime between the 9th and 12th centuries in what is now the Mexican state of Yucatá (Daniel Schwen via Wikimedia Commons)

The scientists say  their findings could have critical implications for understanding the impact of future climate change on human societies. Many global climate models project temperature increases of at least 2 degrees Celsius over the next half century.

The researchers compared extensive data,  spanning from ancient times until today.  Collecting more material than any prior study, the researchers were able to show that the Earth’s climate plays a more influential role in human affairs than previously thought.

Among the historical correlations researchers found was the case of the advanced Mayan civilization which was established around 2000 BC in what is now Mexico and Central America.  Some scholars say this Mesoamerican civilization peaked between the years 250 to 900 AD, when it mysteriously collapsed.

Scientists and historians, including those involved in this study, theorize that climate may have had a lot to do with the Mayan decline and failure.

“The Mayan civilization, the Mayan empire…during the 9th century AD, experienced an unprecedented century of warm, dry weather,” said Miguel. “In fact, they had three mega-droughts during that century and at the end of the third mega-drought, that’s the time at which that civilization collapsed into civil war never to recover its previous grandeur.”

A photo from 2008 showing armed fighters including child soldiers from Al-shabab group in cars outside Mogadishu, Somalia. (AP /Farah Abdi Warsameh/File)

A photo from 2008 showing armed fighters including child soldiers from Al-shabab group in cars outside Mogadishu, Somalia. (AP)

Looking at the link between climate and violence in more modern times, Miguel pointed to hot temperatures and dry conditions in Somalia  and the extreme violence it has endured in recent times.

“When you have temperature spikes on top of what’s already a very hot place, that’s associated with political violence in Somalia, so Somalia is an African case where you can see this come through very clearly,” said Miguel.

The study also found a link between high temperatures and a rise in domestic violence in India.

In Brazil, scientists found a correlation between rainfall and land invasions. Miguel pointed to a landless people’s movement in the South American country that organizes violent raids.

“It turns out that when rainfall is really bad, either way too much or way too little rainfall in a given year, in those years you see spikes in the number of land invasions in Brazil,” said Miguel.

Results of the Berkeley/Princeton research could be used to predict future violent trends and potential trouble spots around the world, which could help in the development of strategies that would address possible violence and conflict in the future.

Drought's impact on a field of corn. (CraneStation/Creative Commons via Flickr)

Drought’s impact on a field of corn. (CraneStation/Creative Commons via Flickr)

“There are at least two different approaches you can take, given these findings,” Miguel said.

The first approach is building better forecasts for where there will be potential violence going forward.

“So if we know, for instance, that temperatures are rising very quickly in a part of the world that is prone to civil conflict, then early on in that year or maybe there’s a drought that year, that is a trouble spot where governments and foreign aid donors and other agencies should focus their efforts,” said Miguel.

The second approach Miguel suggested would be to use the results to really understand just how high the stakes are in dealing with climate change in the next 40 to 50 years.

“[We] could look at the changing climate and try to craft new policies to deal with changing climate,” said Miguel. “We can develop new technologies and approaches that are more resilient to a changing climate. That may be our only way out.”

Professor Edward Miguel joins us this weekend on the radio edition of “Science World.”  He’ll tell us  why a deviation in climate could play a role in determining human behavior.  So, either tune into the show (see right column for scheduled times) or check out the interview below.

>>>> Listen to the interview here

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Studies Disagree on Origins of Monogamy

Posted July 30th, 2013 at 5:33 pm (UTC+0)
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Newly married couple enjoying a sunset (Thejas via Creative Commons/Flickr)

Newly married couple enjoying a sunset (Thejas via Creative Commons/Flickr)

Two new competing studies disagree on the origins of monogamy but both agree it had nothing to do with romance.

Researchers at Cambridge University found social monogamy  originated as a male mating strategy which evolved over the years.  Males pushed for monogamous relationships after finding themselves in situations where females lived far apart from each other or there was a lack of potential female mates, leaving the male unable to dominate and defend multiple mates.

“Where females are widely dispersed, the best strategy for a male is to stick with one female, defend her, and make sure that he sires all her offspring.” said Tim Clutton-Brock, a Cambridge researcher involved with the study. “In short, a male’s best strategy is to be monogamous.”

The other study, led by the University College London, finds the basis for monogamy to be rooted in the  male need to protect its offspring from  unrelated males.

This team  also found that males not only protected their children, but also took on the role of caregiver, sharing childcare tasks with the female, after the idea of monogamy began to take hold.

A family of Barbary macaques in Gibraltar (Harry Mitchell via Wikimedia Commons)

A family of Barbary macaques in Gibraltar (Harry Mitchell via Wikimedia Commons)

“This is the first time that the theories for the evolution of monogamy have been systematically tested, conclusively showing that infanticide is the driver of monogamy,” said Dr Kit Opie, from the University College of London who served as lead author of the study.  “This brings to a close the long running debate about the origin of monogamy in primates.”

The caregiving aspect of the UCL study, say the researchers, became a necessity for primates in particular because they were evolving into creatures that developed much bigger brains than other mammalian species.

Growing a big brain  meant offspring  matured more slowly. With most other animal species, children were left to fend for themselves soon after birth.  In primate species, a prolonged childhood required that both mom and dad be involved with taking care of the offspring, according to the UCL researchers.

They say  this may also explain how large brains were able to evolve in humans.

Science Picture Blog

Posted July 26th, 2013 at 8:01 pm (UTC+0)
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On Thursday NASA officials released this still image of the sun that was taken from a movie imaged by its new sun observing space telescope the Interface Region Imaging Spectrograph, or IRIS.  The movie/image was taken 21 hours after IRIS first opened its telescope door on July 17, 2013. (NASA/IRIS)

This still image of the sun was captured from video taken on July 17, 2013, by IRIS (Interface Region Imaging Spectrograph), NASA’s new sun observing space telescope. (NASA)

No it's not a UFO but it is a 50 foot-wide electromagnet that was transported in one piece some 5,150 km from the US Department of Energy's Brookhaven National Laboratory on Long Island to its Fermilab near Chicago. It took a little over a month to make its long and careful journey.  The gigantic magnet will be used in a new experiment called Muon g-2 that will study the properties of subatomic particles called muons that live only 2.2 millionths of a second. (Brookhaven National Laboratory)

This looks like a UFO, but it’s actually a 50-foot-wide electromagnet that was transported about 5,150 km from the US Department of Energy’s Brookhaven National Laboratory on Long Island and arrived at its Fermilab near Chicago on July 26, 2013, after about a month on the road. (Brookhaven National Laboratory)

This image taken by the wide-angle camera on NASA's Cassini spacecraft, on July 19, 2013, has captured Saturn's rings and our planet Earth (arrow) and its moon in the same frame. (NASA/JPL-Caltech/Space Science Institute)

This image, taken from NASA’s Cassini spacecraft on July 19, 2013, captures Saturn’s rings, Earth (arrow) and Earth’s moon in the same frame. (NASA)

The Moderate Resolution Imaging Spectroradiometer (MODIS) flying aboard NASA’s Aqua satellite took this true-color image of a large phytoplankton bloom in the Norwegian Sea, off of Iceland. The range of colors from milky blue to green suggests that a range of different species make up this bloom. (NASA/Jeff Schmaltz)

This image, taken from NASA’s Aqua satellite, captures the true colors of a large phytoplankton bloom in the Norwegian Sea off Iceland. The range of colors, from milky blue to green, suggests the bloom is made up of a variety of  different species. (NASA)

A team of engineers, from the University of Illinois at Urbana-Champaign, has developed a three-dimensional substance that will help scientists who study brain cancer since it more closely mimics conditions in the brain. The substance called hydrogel is used for growing glioma - brain cancer - cells in a laboratory. This image shows brain cancer cells that were grown in the new hydrogel. The green fluorescent dye reflects the cytoskeletons of the cells. (Brendan Harley)

This three-dimensional substance, developed by a team of engineers from the University of Illinois at Urbana-Champaign, will help scientists study brain cancer since it closely mimics conditions in the brain. The substance is called hydrogel and it’s used to grow brain cancer  cells in a laboratory. (Brendan Harley)

This is the Southern African Large Telescope (SALT) where a team of astrophyscicists led by Dartmouth University recently discovered the extent to which quasars and their black holes can influence their galaxies. The researchers documented the immense power of quasar radiation, reaching out for many thousands of light years to the limits of the quasar's galaxy. The SALT the largest single optical telescope in the southern hemisphere and among the largest in the world.  (Janus Brink, Southern African Large Telescope)

The Southern African Large Telescope (SALT) is the largest single optical telescope in the southern hemisphere. SALT helped a team of astrophyscicists led by Dartmouth University, discover the extent to which quasars and their black holes can influence their galaxies.  (Janus Brink, Southern African Large Telescope)

This NASA/ESA Hubble Space Telescope image shows the planetary nebula IC 289, located in the northern constellation of Cassiopeia. Formerly a star like our sun, it is now just a cloud of ionized gas being pushed out into space by the remnants of the star’s core, visible as a small bright dot in the middle of the cloud.  (European Space Agency)

This NASA/ESA Hubble Space Telescope image shows the planetary nebula IC 289, located in the northern constellation of Cassiopeia. Formerly a star like our sun, it is now just a cloud of ionized gas being pushed out into space by remnants of the star’s core, visible as a small bright dot in the middle of the cloud. (European Space Agency)

A rare glimpse of the titan arum (Amorphophallus titanum), also known as the corpse flower or stinky plant as it bloomed this week at the United States Botanic Garden Conservatory in Washington. The photo shows the plant as it began to open on Sunday, July 21. It started to close on Monday evening, July 22; and collapsed Wednesday evening, July 24. The flower, which requiresd very special conditions, doesn't bloom annually. In fact, the time between flowering is unpredictable, which can span from a few years to a few decades. (AP)

A rare glimpse of the titan arum (Amorphophallus titanum), also known as the corpse flower or stinky plant, as it bloomed this week at the United States Botanic Garden Conservatory in Washington on July 21. The flower requires very special conditions and doesn’t bloom annually. In fact, the time between flowering can span from a few years to a few decades. (AP)

Neutrino Morphing Discovery Could Unlock Mysteries of the Universe

Posted July 23rd, 2013 at 6:47 pm (UTC+0)
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The three types of neutrino - Clockwise from top left - electron neutrino (red), muon neutrino (green) and electron (blue) - The directional arrows indicate how each can morph into different types.  (T2K Experiment)

The three types of neutrino: electron neutrino (red), muon neutrino (green) and electron (blue). The directional arrows indicate how each can morph into different types. (T2K Experiment)

Scientists meeting in Stockholm say they’ve confirmed that subatomic particles known as neutrinos have the ability to morph from one type of the particle into another. The finding could one day help scientists explain why the universe contains matter but very little antimatter.

Neutrinos, one of the fundamental building blocks of matter, come in three distinct types or flavors: electron, muon or tau.  These particles have no electrical charge but their mass can vary by flavor.  An electron neutrino has a mass no greater than 2.2 eV (electron volts). The muon neutrino can have a mass that is less than 170 KeV (kilo-electron volts).  The tau neutrino, which has a mass of less than 15.5 MeV (mega-electron volts), was discovered in 2000 at the US Department of Energy’s Fermilab near Chicago.

Scientists produced a beam of muon neutrinos at the Japan Proton Accelerator Research Complex (J-PARC) near Japan’s east coast and aimed it at the gigantic Super-Kamiokande underground detector in Kamioka, 295 km away, near Japan’s west coast.  They discovered that some of the muon neutrinos had morphed into electron neutrinos somewhere along the journey.

Physicists know these three different neutrino flavors have the ability to freely change from one type into another through a phenomenon called neutrino oscillations. However, the new findings made by the T2K (Tokai to Kamioka) team, mark the first discovery of electron neutrinos showing up in a beam of muon neutrinos.

Illustration of the Super Kamiokande detector. It's the world’s largest underground neutrino detector that found electron neutrinos within a beam of muon neutrinos. (T2K experiment)

Illustration of the Super Kamiokande detector, the world’s largest underground neutrino detector, that found electron neutrinos within a beam of muon neutrinos. (T2K experiment)

“Understanding the properties of neutrinos in more detail would give an important clue to solving the riddle of how the universe has come to exist,” Takashi Kobayashi, a member of the T2K team, told the Japan News.

This new way of observing neutrino oscillation is the key for scientists to be able to make measurements that would allow them to distinguish the different oscillations of neutrinos and its anti-particle counterpart anti-neutrinos.  This is something that could help in better understanding the physical processes that involve matter and antimatter.

“We have seen a new way for neutrinos to change, and now we have to find out if neutrinos and anti-neutrinos do it the same way,” said Professor Dave Wark, who helped lead the international T2K experiment. “If they don’t, it may be a clue to help solve the mystery of where the matter in the universe came from in the first place. Surely answering that is worth a couple of decades of work.”

Astronomers Spot Snow in Deep Space

Posted July 19th, 2013 at 8:01 pm (UTC+0)
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Artist concept of snow line in TW Hydrae showing water covered ice grains colored blue in the inner disk and green colored CO ice covered grains in the outer disk. (Bill Saxton and Alexandra Angelich, NRAO/AUI/NSF)

Artist concept of snow line in TW Hydrae showing water covered ice grains colored blue in the inner disk and green colored CO ice covered grains in the outer disk. (Bill Saxton and Alexandra Angelich, NRAO/AUI/NSF)

New fallen snow on a crisp winter morning can be a beautiful and inspiring sight.  But astronomers using the new Atacama Large Millimeter/submillimeter Array (ALMA) in Chile got really got a real thrill recently when they saw and imaged a snow fall in a very young solar system some 175 light years from Earth.

The astronomers say that this never-before-seen icy feature may play an important role in providing scientists with insight into the chemical make-up and the way that both comets and developing planets take shape.

Up until now, these alien snow lines have never been directly imaged and could only be spotted by their spectral signatures – a specific pattern of electromagnetic radiation that is used to identify a chemical or compound.

In a study published yesterday in Science Express, the authors speculate that the solar system where they found the deep space snow line surrounds a young star called TW Hydrae and that this solar system has many of the same characteristics that our own did when it was only a few million years old.

According to the research team’s co-leader, Chunhua “Charlie” Qi, from the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass, “ALMA has given us the first real picture of a snow line around a young star, which is extremely exciting because of what it tells us about the very early period in the history of our own Solar System.  We can now see previously hidden details about the frozen outer reaches of another solar system, one that has much in common with our own when it was less than 10 million years old.”

Here on Earth snow lines that can often be seen near the summit of mountains are usually formed when freezing or sub-freezing temperatures, that are common at high elevations, turn atmospheric water vapor into snow.

The astronomers said that the snow lines found in the outer reaches of young solar systems are formed pretty much the same way as they do on Earth. But instead of simply water vapor freezing and turning into ice and snow like here on Earth, the scientists said that the frozen material found in the distant solar system are formed when gases such as methane, carbon dioxide and carbon monoxide form layers and freeze around grains of interplanetary dust.

ALMA image of the region where snow made of carbon monoxide (CO) has formed around the star TW Hydrae (center). (Karin Oberg, Harvard University/University of Virginia)

ALMA image of the region where snow made of carbon monoxide (CO) has formed around the star TW Hydrae (center). (Karin Oberg, Harvard University/University of Virginia)

They add that even more unusual molecules can also freeze and turn into snow and ice, depending how far the materials are from its star. Also, molecules like carbon monoxide are able to freeze a lot easier when they’re insulated by a surrounding fog of concentrated dust and gas.

It’s that insulation that surrounds the frozen matter that has kept scientists from getting a good look, until now, at the icy element hidden inside.

“It would be like trying to find a small, sunny patch hidden within a dense fogbank,” said the research team’s other co-leader Karin Oberg, from Harvard University and the University of Virginia in Charlottesville.

The astronomers behind this discovery said that they were able to poke through that insulating fog of gas by looking for molecules known diazenylium or N2H+, which can be spotted at great distances by a sensitive and advanced radio telescope like ALMA.  Since the substance doesn’t survive when it’s in the presence of carbon monoxide – CO, the researchers came to realize that finding the fragile molecule would indicate that the carbon monoxide gas surrounding it was frozen.

“Using this technique, we were able to create, in effect, a photonegative of the CO snow in the disk surrounding TW Hydrae,” said Oberg. “With this we could see the CO snow line precisely where theory predicts it should be — the inner rim of the diazenylium ring.”

Snow lines, like the one found in the TW Hydrae solar system, are believed by astronomers to play an important part in the formation of a solar system.

They say that the frozen material surrounding the grains of planet-and-comet-forming dust provides it with a sticky coating which prevents the particles from self-destructing by smashing into each other.  Scientists also theorize that the ice-covered dust grains help increase the amount of solids available and may dramatically speed up the planet formation process.

Antennas that make up the ALMA array of radio telescopes located on Chile's Chajnantor Plateau (ALMA (ESO/NAOJ/NRAO), O. Dessibourg)

Antennas that make up the ALMA array of radio telescopes located on Chile’s Chajnantor Plateau (ALMA (ESO/NAOJ/NRAO), O. Dessibourg)

Since many different kinds of snow lines have been found, each variety may be linked to the formation of specific kinds of planets, according to the research team.

For example, in our own solar system a snow line formed from water could be located where Jupiter currently orbits the Sun and a snow line made from carbon monoxide would correspond to the Neptune’s solar orbit. They also speculate that an area of space where the snow line transitions to one made from CO could also denote the beginning of a region within a solar system where smaller icy bodies such as dwarf planets like Pluto as well as comets would develop.

The scientists said that they found CO snow lines especially interesting, since ice made with carbon monoxide is an important ingredient in making methanol or methol-alcohol, which they say is an element of more complex organic molecules essential for the formation of life.  They think that comets and asteroids could then transport these molecules to developing Earth-like planets and seed them with the components that would help foster life.

Scientists See Processes Behind Major Solar Events

Posted July 16th, 2013 at 7:25 pm (UTC+0)
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An overlap of data from two NASA spacecraft confirm a sighting of magnetic reconnection on the sun. The teal image, from SDO, shows the shape of magnetic field lines in the sun’s atmosphere, the RHESSI data, in orange. (NASA/SDO/RHESSI/Goddard)

An overlap of data from two NASA spacecraft confirm a sighting of magnetic reconnection on the sun. The teal image, from SDO, shows the shape of magnetic field lines in the sun’s atmosphere, the RHESSI data, in orange. (NASA/SDO/RHESSI/Goddard)

Over the past several years, NASA spacecraft studying the sun have sent back some spectacular images of it exploding with solar flares and coronal mass ejections.  Now, scientists say that two of these spacecraft — the Solar Dynamics Observatory (SDO) and the Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) — have detected a phenomenon called magnetic reconnection, what they describe as the ‘Heart of Space Weather’ in action.

NASA describes magnetic reconnection as something that takes place whenever the sun’s magnetic field lines first unite, arch out, break apart, reconnect with different magnetic fields, then snap into new positions, releasing a pulse of magnetic energy along the way.  Scientists believe that the magnetic reconnection process is what’s behind enormous explosions on the sun that can hurl radiation and various energy related particles across the entire solar system.

If they could get a better understanding of this process, the scientists say, they may be able to develop new methods that would allow for much more advanced and detailed warnings on upcoming space weather events.  These events, like the solar flares and coronal mass ejections, or CMEs, can wreak havoc with orbiting satellites, radio communications and even the world’s power grids.

NASA's Solar Dynamics Observatory captured this image of an M6.5 class flare. This image shows a combination of light in wavelengths of 131 and 171 Angstroms - light wavelength measurement.- (NASA/SDO)

NASA’s Solar Dynamics Observatory captured this image of an M6.5 class flare. This image shows a combination of light in wavelengths of 131 and 171 Angstroms – light wavelength measurement.- (NASA/SDO)

One reason why it’s so hard to study magnetic reconnection is that it can’t be witnessed directly because magnetic fields are invisible. Instead, scientists have been using a combination of computer modeling and a scant sampling of observations around magnetic reconnection events to try to understand what’s going on.

“The community is still trying to understand how magnetic reconnection causes flares,” said Yang Su, a solar scientist at the University of Graz in Austria. “We have so many pieces of evidence, but the picture is not yet complete.”

Su found some new visual proof of this phenomenon as he was pouring through observations that had been made by the SDO spacecraft.  It was something that would have been very difficult to find by using SDO data alone; the scientist actually found some direct images of magnetic reconnection itself taking place on the sun.

What the scientist saw was were two bundles of the magnetic field lines shift near each other, which then meet briefly to form what seemed to be an “X,” and then blast apart from each other with one group of lines leaping into space and while another set fell back down into the sun.

Now, since the magnetic fields themselves are invisible, they can be seen by space telescopes as bright lines that loop and arc throughout the sun’s atmosphere.  These visible bright line lines are actually the magnetic fields lined with plasma — material made up of force charged particles that make up much of the sun — that pulse up and along the length of the fields.

When magnetic fields lines on the sun come together they can realign into a new configuration. The process, called magnetic reconnection, can produce tremendous amounts of energy, powering gigantic explosions in the sun’s atmosphere. (NASA Goddard)

When magnetic fields lines on the sun come together they can realign into a new configuration. The process, called magnetic reconnection, can produce tremendous amounts of energy, powering gigantic explosions in the sun’s atmosphere. (NASA Goddard)

“It can often be hard to tell what’s truly happening in three dimensions from these images, since the pictures themselves are two-dimensional,” said Gordon Holman, a solar scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “But if you look long enough and compare data from other instruments, you can make a good case for what’s going on.”

To get conformation of what the scientists were actually seeing, they went to a second spacecraft that’s keeping an eye on the sun, the Reuven Ramaty High Energy Solar Spectroscopic Imager, or RHESSI.  This spacecraft gathers data to form spectrograms that can show researchers where extremely hot material may be present during various solar events.

In confirming the images scientists gathered from the SDO, the spectrograms produced by the RHESSI showed that there were hot pockets of solar material forming both above and beneath magnetic reconnection points, which provided the scientists with an established signature of the reconnection event.

Combining the images and data from both the SDO and RHESSI, scientists were then able to describe what they were actually seeing.  Putting together the studies with information from both spacecraft allowed the scientists to confirm many previous models and theories. And at the same time, they were able to provide some new, three-dimensional aspects of the magnetic reconnection process.

The research and findings were outlined in the July 14th edition of the journal Nature Physics.

NASA video explains what the SDO and RHESSI spacecraft captured

Far-away Planet Found to be Same Color as Earth

Posted July 12th, 2013 at 7:16 pm (UTC+0)
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Artist's Impression of the Deep Blue Planet HD 189733b (NASA, ESA, M. Kornmesser)

Artist’s impression of the deep blue planet HD 189733b (NASA)

The Hubble Space Telescope has helped scientists determine the color of a planet outside of our Solar System for the first time.

Located about 63 light years from Earth, the planet known as HD 189733b would be a deep cobalt blue if viewed at close range, similar to Earth’s color as seen from space.

Despite the comparable colors, that’s where the similarities between Earth and the exoplanet end, researchers say.  Astronomers describe the planet, referred to as a “deep blue dot,” as a huge gas giant orbiting close to its host star, HD 189733, which is located in the constellation of Vulpecula, the Fox.

The planet’s atmosphere has a blazing temperature of over 1,000 degrees Celsius, and when it rains there, it rains hot molten glass that falls sideways due to violent 7,000 kilometer-per-hour winds.

The HD 189733 system (circled) is located in Constellation Vulpecula--near Cygnus. (Akira Fujii and Zolt Levay via Wikimedia Commons)

The HD 189733 system (circled) is located in Constellation Vulpecula, near Cygnus. (Akira Fujii and Zolt Levay via Wikimedia Commons)

HD 189733b is one of the closest extra-solar planets to Earth that can be observed to cross the face of its star.  Its atmosphere, researcher say, is unsettled and unusual in nature, “with hazes and violent flares.”

“This planet has been studied well in the past, both by ourselves and other teams,” said Frederic Pont from the University of Exeter. “But measuring its color is a real first; we can actually imagine what this planet would look like if we were able to look at it directly.”

The research team was able to determine the exoplanet’s color by measuring how much light reflected off its surface, a property known as albedo, or a reflection coefficient.

Astronomers say HD 189733b is faint compared to surrounding objects. Since the planet is so close to its bright star, the researchers had to isolate its light from the starlight.  To do this, the team used Hubble’s Space Telescope Imaging Spectrograph (STIS) to study the planet/star system before, during, and after the exoplanet went behind its star during orbit.

The Hubble in orbit above the Earth (Photo: NASA)

The Hubble in orbit above the Earth (NASA)

“We saw the brightness of the whole system drop in the blue part of the spectrum when the planet passed behind its star,” said the study’s first author, Tom Evans from the University of Oxford. “From this, we can gather that the planet is blue, because the signal remained constant at the other colors we measured.”

Unlike the Earth, HD 189733b’s cobalt blue color does not come from the reflection of oceans, but rather from its hazy and stormy atmosphere which scientists think may be mixed with silicate particles that disperse blue light.

“It’s difficult to know exactly what causes the color of a planet’s atmosphere, even for planets in the Solar System,” said Pont. “But these new observations add another piece to the puzzle over the nature and atmosphere of HD 189733b. We are slowly painting a more complete picture of this exotic planet.”

Curiosity Begins Mars Roadtrip

Posted July 9th, 2013 at 5:42 pm (UTC+0)
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This mosaic of images from the Mast Camera (Mastcam) on NASA's Mars rover Curiosity shows the rover's destination Mount Sharp in a white-balanced color adjustment that makes the sky look overly blue but shows the terrain as if under Earth-like lighting. (NASA/JPL/MSL)

This mosaic of images from the Mast Camera on NASA’s Mars rover shows Curiosity’s destination: Mount Sharp. A white-balanced color adjustment makes the sky look overly blue, but also shows the terrain as if under Earth-like lighting. (NASA)

Curiosity has taken off on a year-long roadtrip, which is how long it will take the Mars rover to travel the eight kilometers needed to reach its Mount Sharp destination.

NASA said the journey began last week from an area called Glenelg, which is about 400 meters east-southeast of Curiosity’s landing site.  According to mission officials, the rover drove about 18 meters toward Mount Sharp on July 4, and another 40 meters on July 7, traveling a total of about 58 meters toward its destination, with 7,942 meters to go.

Curiosity can travel an average of 30 meters per hour – depending on variables such as power levels, slippage, steep terrain and visibility – but the rover will take its time getting to Mount Sharp, stopping, or possibly backtracking, should it spot something of interest. Challenging terrain could also slow the rover’s progress.

This view from the left Navigation Camera (Navcam) of NASA's Mars Rover Curiosity looks back at wheel tracks made during the first drive away from the last science target in the "Glenelg" area. The drive commenced a long trek toward the mission's long-term destination: Mount Sharp.  (NASA/JPL/MSL)

NASA’s Mars Rover Curiosity looks back at wheel tracks made during the first drive away from the  Glenelg area, as it heads towards the foothills of Mount Sharp. (NASA)

The mission team is anxious for Curiosity to explore the lower layers of Mount Sharp, where they expect to find evidence of how the ancient Martian environment changed and evolved.

Each of the layers offers an opportunity to look back into Mars’ geological history, said Rob Manning, the Mars Science Laboratory’s (MSL) chief engineer. Curiosity’s mission to Mars is scheduled to last one Martian year, about 687 Earth days.  But, if the rover continues to operate, NASA could extend its mission, allowing Curiosity to continue its journey up Mount Sharp.

“We will continue going up and explore and explore,” Manning said.

Since beginning its mission after last August’s landing, Curiosity has made a number of discoveries, including finding evidence of an ancient wet environment with conditions favorable for microbial life.

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