Astronomers Detect a Galaxy Far, Far Away

Posted May 6th, 2015 at 11:12 pm (UTC-4)
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The galaxy EGS-zs8-1 sets a new distance record. It was discovered in images from the Hubble Space Telescope from the CANDELS survey.  (NASA, ESA, P. Oesch and I. Momcheva (Yale University), 3D-HST and HUDF09/XDF Teams)

The galaxy EGS-zs8-1 sets a new distance record. It was discovered in images from the Hubble Space Telescope from the CANDELS survey. (NASA, ESA, P. Oesch and I. Momcheva (Yale University), 3D-HST and HUDF09/XDF Teams)

Astronomers have discovered the most distant galaxy ever detected, gaining new insight into the early beginnings of our universe.

Identified as EGS-zs8-1, the international team of astronomers measured its exact distance at 13 billion light years away from Earth. That means that light from the galaxy now reaching Earth was produced back when the universe was only 5% of its present age.

Astronomers say the galaxy was one of the most enormous and brightest objects in the early universe.

The team also found that, 13 billion years ago, this distant galaxy was forming stars some 80 times faster than our galaxy does today.

“It has already built more than 15% of the mass of our own Milky Way today,” said Pascal Oesch, a Yale astronomer in a press release.

W. M. Keck Observatory located near the summit of Mauna Kea in Hawaii (T. Wynne/JPL)

W. M. Keck Observatory located near the summit of Mauna Kea in Hawaii (T. Wynne/JPL)

The team’s observations of galaxy EGS-zs8-1, as it existed so many years ago, also provided evidence that the universe at its early age, was going through some significant changes.

They found that intergalactic hydrogen was evolving from a neutral or normal state into an ionized state.

“It appears that the young stars in the early galaxies like EGS-zs8-1 were the main drivers for this transition, called reionization,” said Rychard Bouwens of the Leiden Observatory.

The astronomers, led by Yale University and the University of California-Santa Cruz, were able to determine the exact distance of EGS-zs-8-1 by using the powerful Multi-Object Spectrometer for Infra-Red Exploration or MOSFIRE instrument.

This device, which lets astronomers effectively conduct research on several galaxies at the same time, was installed in 2012 on the Keck 1 telescope at the W. M. Keck Observatory in Hawaii.

The distant EGS-zs8-1 galaxy was first identified by its particular colors that appeared in images from NASA’s Hubble and Spitzer space telescopes.

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

Astronomers Observe Exoplanet Temperatures Swinging Wildly

Posted May 4th, 2015 at 11:06 pm (UTC-4)
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Artist rendering of super-Earth exoplanet 55 Cancri e in close orbit with its sun. (NASA)

Artist rendering of super-Earth exoplanet 55 Cancri e in close orbit with its sun. (NASA)

For the first time ever, scientists in the United Kingdom detected temperature fluctuations on a super-Earth exoplanet – 55 Cancri e, the so-called “diamond planet.”

Using NASA’s Spitzer Space Telescope to study the rocky exoplanet’s thermal radiation over a two-year period, researchers led by the University of Cambridge found that the temperature on the side of the planet facing its nearby sun rapidly shifted between 1,000-2,700 degrees Celsius.

55 Cancri E is tidally locked, which means that it doesn’t rotate on its axis like Earth. So it has a permanent ‘day’ side that always faces its sun, and a permanent ‘night’ side – always away from its sun.

“This is the first time we’ve seen such drastic changes in light emitted from an exoplanet, which is particularly remarkable for a super-Earth,” said Nikku Madhusudhan of the University of Cambridge’s Institute of Astronomy in a press release.

Madhusudhan, who is also the co-author of a study published in the Monthly Notices of the Royal Astronomical Society, said “no signature of thermal emissions or surface activity has ever been detected for any other super-Earth to date.”

Past observations reveal that 55 Cancri e is a rocky exoplanet that is about twice the size of Earth and has eight times its mass. It orbits its parent star from such a close distance that one year there is only 18 hours long.

Artist impression showing surface of the rocky exoplanet 55 Cancri e with its sun in the background (Ron Miller/NASAblueshift)

Artist impression showing surface of the rocky exoplanet 55 Cancri e with its sun in the background (Ron Miller/NASAblueshift)

Along with five other exoplanets, 55 Cancri E orbits 55 Cancri, a Sun-like star located about 40 light years away in the Cancer constellation.

Back in 2012, Madhusudhan, then a researcher at Yale University, was lead author of a study that found that 55 Cancri e’s chemistry was much different from Earth. He and his colleagues found that the exoplanet’s surface was probably covered in graphite and diamond rather than water and granite like Earth.

It is now thought that the results of the new study may throw doubt on those earlier observations and that further study of the planet’s possible chemical composition is needed.

“When we first identified this planet, the measurements supported a carbon-rich model,” said Madhusudhan. “But now we’re finding that those measurements are changing in time. The planet could still be carbon rich, but now we’re not so sure. Earlier studies of this planet have even suggested that it could be a water world.”

Analysis of data is at an early stage, but the researchers think that enormous clouds of gas and dust that occasionally cover the exoplanet’s surface may be a contributing factor to the wide fluctuation of temperatures.

The researchers believe that these clouds of gas and dust, which could be partially molten, could be caused by a remarkably high amount of volcanic activity on 55 Cancri e.

“While we can’t be entirely sure, we think a likely explanation for this variability is large-scale surface activity – possibly volcanism … spewing out massive volumes of gas and dust, which sometimes blanket the thermal emission from the planet so it is not seen from Earth,” said the study’s lead author, Brice-Olivier Demory of the University of Cambridge’s Cavendish Laboratory.

Demory said the researchers observed “300 percent change in the signal coming from this planet, which is the first time we’ve seen such a huge level of variability in an exoplanet.”

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

The Best Science Images – April 2015

Posted April 29th, 2015 at 8:26 pm (UTC-4)
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The Calbuco volcano, near Puerto Varas, Chile, recently erupted for the first time in more than 42 years.  Here’s a spectacular photo of the volcano erupting the night of 4/23/15. (AP)

The Calbuco volcano, near Puerto Varas, Chile, recently erupted for the first time in more than 42 years. Here’s a spectacular photo of the volcano erupting the night of 4/23/15. (AP)

This photo taken from outer space by NASA’s Earth observing Terra satellite on 4/23/15 shows an ash plume rising from the erupting Calbuco volcano in southern Chile. (NASA’s Earth Observatory)

This photo taken from outer space by NASA’s Earth observing Terra satellite on 4/23/15 shows an ash plume rising from the erupting Calbuco volcano in southern Chile. (NASA’s Earth Observatory)

Here’s a view of the shortest lunar eclipse of the century as seen from the Echo Park district of Los Angeles on 4/4/15.  (AP)

A view of the shortest lunar eclipse of the century as seen from the Echo Park district of Los Angeles on 4/4/15. (AP)

Apple fans were excited when the highly anticipated Apple Watch was recently released.  Here a customer tries on the Apple Watch Edition at the Eaton Centre Apple Store, in Toronto on 4/10/15.  (AP)

Apple fans were excited when the highly anticipated Apple Watch was recently released. Here a customer tries on the Apple Watch Edition at the Eaton Centre Apple Store, in Toronto on 4/10/15. (AP)

A SpaceX Falcon 9 rocket, carrying a Dragon cargo spacecraft, was launched from Cape Canaveral Air Force Station in Florida on 4/14/15. (NASA)

A SpaceX Falcon 9 rocket, carrying a Dragon cargo spacecraft, was launched from Cape Canaveral Air Force Station in Florida on 4/14/15. (NASA)

The Dragon spacecraft, seen here in this image from NASA-TV, is about to be grappled by the International Space Station’s robotic arm as it arrives on 4/16/15.  The cargo ship delivered nearly 2,000 kg of food, science experiments, equipment and the first espresso maker in space to the 6 ISS crewmembers (NASA)

The Dragon spacecraft, seen here in this image from NASA-TV, is about to be grappled by the International Space Station’s robotic arm as it arrives on 4/16/15. The cargo ship delivered nearly 2,000 kg of food, science experiments, equipment and the first espresso maker in space to the 6 ISS crewmembers (NASA)

A robot plays the ball during a soccer match during the RoboCup German Open 2015 in Magdeburg, Germany on 4/24/15.  Around 200 robotic teams from 14 countries demonstrated state-of-the-art robotics with a variety of competitions (AP)

A robot plays the ball during a soccer match during the RoboCup German Open 2015 in Magdeburg, Germany on 4/24/15. Around 200 robotic teams from 14 countries demonstrated state-of-the-art robotics with a variety of competitions (AP)

Researchers recently found evidence, in this image of NGC 6388, that a white dwarf star may have ripped apart a planet as it came too close.  The image of the globular cluster was captured by NASA's Chandra X-ray Observatory. (NASA)

Researchers recently found evidence, in this image of NGC 6388, that a white dwarf star may have ripped apart a planet as it came too close. The image of the globular cluster was captured by NASA’s Chandra X-ray Observatory. (NASA)

Japan’s space agency JAXA recently announced that it is considering an unmanned mission to the moon by 2018 or early 2019.  This is an artist’s rendering of the proposed Japanese lunar spacecraft SLIM (Smart Lander for Investigating Moon) as it is about to touch down on the lunar surface (Japan Aerospace Exploration Agency via AP)

Japan’s space agency JAXA recently announced that it is considering an unmanned mission to the moon by 2018 or early 2019. This is an artist’s rendering of the proposed Japanese lunar spacecraft SLIM (Smart Lander for Investigating Moon) as it is about to touch down on the lunar surface (Japan Aerospace Exploration Agency via AP)

After orbiting Mercury for a little over four years, NASA’s MESSENGER mission is scheduled to come to an end on 4/30/15 when it runs out of fuel and crashes into the surface of the planet.  The MESSENGER sent back one its final images on 4/26/15.  (NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

After orbiting Mercury for a little over four years, NASA’s MESSENGER mission is expected to come to an end on 4/30/15 when it runs out of fuel and crashes into the surface of the planet. The MESSENGER sent back one its final images on 4/26/15. (NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington)

This is the Noor I solar power plant near Ouarzazate, Morocco on 4/24/15.  Construction of the 160 megawatt solar power station is nearly complete. (AP)

This is the Noor I solar power plant near Ouarzazate, Morocco on 4/24/15. Construction of the 160 megawatt solar power station is nearly complete. (AP)

NASA/NOAA Suomi National Polar-orbiting Partnership spacecraft captured this combination image of Southern Africa and the surrounding oceans on 4/9/15 and released it to the public on 4/21/15 just in time for Earth Day the following day.  Note: Tropical Cyclone Joalane can be seen (upper right side) over the Indian Ocean.  (Ocean Biology Processing Group/Goddard Space Flight Center)

NASA/NOAA Suomi National Polar-orbiting Partnership spacecraft captured this combination image of Southern Africa and the surrounding oceans on 4/9/15.  They released it to the public on 4/21/15 just in time for Earth Day the following day. Note: Tropical Cyclone Joalane can be seen (upper right side) over the Indian Ocean. (Ocean Biology Processing Group/Goddard Space Flight Center)

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

Calling ET: NASA Expands Search for Alien Life

Posted April 27th, 2015 at 10:48 pm (UTC-4)
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(NASA)

(NASA)

The search for life beyond our own solar system has taken a major step forward with a new interdisciplinary research coalition devoted to the search for life in the cosmos.

Nexus for Exoplanet System Science (NExSS) will be made up of research teams from several NASA facilities, 10 U.S. universities and two research institutions, according to a recent NASA announcement.

Research teams were picked from proposals submitted to the four various divisions that make-up the space agency’s Science Mission Directorate.

NExSS experts will search for life in the cosmos by studying various aspects of a extra solar planet or exoplanet, as well as how the planet’s star and neighboring worlds all act together to support life.

NASA said NExSS researchers will be better equipped to look for life on extrasolar planets if they gain a better understanding of how biology interacts with various components of an exoplanet, such as its interior, atmosphere, geology and ocean, and how its host star affects these interactions.

“This interdisciplinary endeavor connects top research teams and provides a synthesized approach in the search for planets with the greatest potential for signs of life,” said Jim Green, NASA’s Director of Planetary Science in a press release.

Artist rendering of 51 Pegasi by Celestia Français (Kirk39/Wikimedia Commons)

Artist rendering of 51 Pegasi b the first discovered exoplanet.  (Calista Francais/Kirk39/Wikimedia Commons)

He said “the hunt for exoplanets is not only a priority for astronomers, it’s of keen interest to planetary and climate scientists as well.”

As more and more planets are found in solar systems beyond our own, researchers have been working on scientific methods that would not only allow them to confirm whether the alien planets are suitable to host life, but also help them look for specific biosignatures that point to the presence of life on these planets.

Experts from the four divisions of NASA’s Science Mission Directorate will provide NExSS with guidance and knowledge in the areas of Earth Science, Planetary Science, Helieophysics and Astrophysics. And NExSS team members will study and classify newly discovered exoplanets, determine if they are possibly habitable, and develop the needed tools and technologies to find life beyond our own planet.

“NExSS scientists will not only apply a systems science approach to existing exoplanet data, their work will provide a foundation for interpreting observations of exoplanets from future exoplanet missions such as TESS, JWST, and WFIRST,” noted Paul Hertz, director of the Astrophysics Division at NASA Headquarters, Washington.

The TESS or Transiting Exoplanet Survey Satellite mission is scheduled for a 2017 launch date. The JWST or James Webb Space Telescope – Hubble’s replacement – is set to be launched in 2018.  And NASA is now studying the WFIRST or Wide-field Infrared Survey Telescope which they hope to launch sometime in the 2020s.

The first extrasolar planet was discovered only 20 years ago when 51 Pegasi b was found orbiting 51Pegasi, a main sequence star much like our own Sun, some 50 light years away.

After NASA’s Kepler space telescope went into operation in May 2009, scientists were able to confirm the existence of more than 1,800 exoplanets.

Thousands more await confirmation.

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

Giant Magma Reservoir Found Beneath Yellowstone Supervolcano

Posted April 23rd, 2015 at 6:00 pm (UTC-4)
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The gorgeous colors of Yellowstone National Park’s Grand Prismatic hot spring are among the park’s many hydrothermal features created by the fact that Yellowstone sits above a supervolcano – the largest type of volcano on Earth. (Robert B. Smith & Lee J. Siegel)

Yellowstone National Park’s Grand Prismatic hot spring are among the park’s many hydrothermal features. (Robert B. Smith & Lee J. Siegel)

Yellowstone National Park’s many geothermal features, including its estimated 10,000 hot springs and geysers, draw millions of visitors each year.

There’s good reason why the approximately 8,983 square km park has such a high level of geothermal activity. You see, the park sits atop one of the world’s largest active volcanic systems.

According to the US Geological Survey, Yellowstone’s supervolcano exploded with three cataclysmic volcanic eruptions over the past 2.1 million years. The most recent took place about 640,000 years ago.

Scientists say those three catastrophic Yellowstone supervolcano eruptions covered much of North America in volcanic ash. A similar eruption today would be equally devastating, according to researchers.

Today, a number of people – possibly inspired by a few conspiracy theories and docudrama television programs – are concerned that a significant and catastrophic eruption of Yellowstone’s supervolcano is imminent.

And seismologists from the University of Utah have made a new discovery that may add to these concerns.

This cross-section illustration - cutting southwest-northeast - under Yelowstone depicts the supervolcano's "plumbing system" as revealed by recent seismic imaging. (Hsin-Hua Huang, University of Utah)

This cross-section illustration – cutting southwest-northeast under Yelowstone – depicts the supervolcano’s “plumbing system” as revealed by recent seismic imaging. (Hsin-Hua Huang, University of Utah)

The scientists said they discovered and made images of a reservoir of hot and partially molten rock located about 19 to 45 km below the Yellowstone supervolcano. The researchers added that this reservoir is about 4.4 times larger than the long-known and shallower magma chamber above.

According to Jamie Farrell, a co-author of a study published in the journal Science, the reservoir of hot rock would fill the 4,168 cubic kilometer Grand Canyon 11.2 times. The magma chamber above it was calculated to fill the Grand Canyon 2.5 times.

“For the first time, we have imaged the continuous volcanic plumbing system under Yellowstone,” said the study’s first author Hsin-Hua Huang, a postdoctoral researcher in geology and geophysics, in a press release.

“That includes the upper crustal magma chamber we have seen previously plus a lower crustal magma reservoir that has never been imaged before and that connects the upper chamber to the Yellowstone hotspot plume below,” he added.

To allay any fears that the Yellowstone volcano is about to blow up, the seismologists emphasized that its “plumbing system” is neither larger nor is it any closer to erupting than before.

Robert Smith, a research and emeritus professor of geology and geophysics at the University of Utah, took this a step further, saying the annual chance of the supervolcano erupting is 1 in 700,000.

One of the most popular hydrothermal features at Yellowstone park is the geyser Old Faithful, shown here during one of its regular eruptions. (Jon Sullivan/Wikimedia Commons)

One of the most popular hydrothermal features at Yellowstone park is the geyser Old Faithful, shown here during one of its regular eruptions. (Jon Sullivan/Wikimedia Commons)

The researchers also stressed that contrary to what many people may think, the magma chamber beneath the Yellowstone supervolcano and the magma reservoir beneath that are not bubbling with molten rock. While the rock material is hot, the researchers said it’s mostly solid and spongy, with only pockets of molten rock within it.

The hot rock in the upper magma chamber contains an average of about nine percent molten rock, according to researchers’ calculations. That is pretty much in line with past estimates of between 5-15 percent of molten rock in that chamber. The researchers also found that the contents in the lower magma reservoir are made of about two percent of melted rock.

Study co-author Fan-Chi Lin, assistant professor of geology and geophysics, said that the new research is providing a “better understanding the Yellowstone magmatic system.”

“We can now use these new models to better estimate the potential seismic and volcanic hazards,” he said.

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

Read My Lips: Researchers Develop New Automated Film Dubbing Technique

Posted April 20th, 2015 at 7:00 pm (UTC-4)
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A series of facial movements that are used when pronouncing phrases listed on the right (Disney Research

A series of facial movements that are used when pronouncing phrases listed on the right (Disney Research)

Sixteen days after its April 3, 2015 release, the new American action film “Furious 7” made a whopping $858.3 million in international markets, compared to a more modest $294.4 million in North America. Movie and television programs companies have taken notice and are aggressively marketing their products to a wide international audience.

But reaching an international audience means the film’s dialog must often be dubbed by actors speaking local languages.

Current methods of dubbing dialogue to match the on screen facial movements of the person talking as closely as possible often come across as terribly disjointed. That makes for an unpleasant movie viewing experience for the audience.

Given such a lucrative international market, filmmakers are taking extraordinary steps to ensure that the translated version’s sound matches the facial movements of onscreen actors as closely to as possible.

Disney Research, Pittsburgh and the United Kingdom’s University of East Anglia have conducted studies that they said will help in the development an automated dialogue re-dubbing system that will make movies more enjoyable for people who speak the languages spoken by international audiences.

This is a movie dubbing studio where dialogue is translated and revoiced into other languages and then dubbed into movies set for international release. (arceus555 via Creative Commons)

This is a movie dubbing studio where dialogue is translated and revoiced into other languages and then dubbed into movies set for international release. (arceus555 via Creative Commons)

The new system, developed by a team led by Sarah Taylor at Disney Research, Pittsburgh, automatically analyzes the on screen actor’s speech. It then allows film producers to reduce or in some cases eliminate even the most subtle differences between words spoken on screen and what the audience hears.

The system is based on something called “dynamic visemes,” which are facial movements that are connected with certain sounds produced in speech.

“The method using dynamic visemes produces many more plausible alternative word sequences that are perceivably better than those produced using a static viseme approaches,” Taylor said in a press release.

The system will provide filmmakers with a wider variety of word sequences that match facial movements.  This will allow producers to write local language dialogue that not only corresponds with the movie’s script, but also ensures that on-screen facial movements are more in synchronization with what the audience hears.

As an example, the researchers found that when an actor says a phrase like “clean swatches,” his facial movements are the same as those for other phrases, such as “likes swats,” “then swine,” or “need no pots.”

Taylor and her research team will present their findings on April 23 at the 40th International Conference on Acoustics, Speech and Signal Processing (ICASSP), that’s being held from April 19-24, 2015, in Brisbane, Australia.

How the new technique will affect international revenues remains unclear. While Furious 7 has performed well at the international box office so far, it still needs to earn at least another $1.17 to beat out James Cameron’s 2009 blockbuster Avatar – the all-time international money-making film that has earned nearly $2.03 in international receipts.


Video demonstrates new dubbing method developed by Disney Research (Disney Research)

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

Scientists Find Evidence of Liquid Water on Mars

Posted April 14th, 2015 at 2:27 pm (UTC-4)
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An artist’s impression shows how Mars may have looked about four billion years ago. (ESO/M. Kornmesser/N. Risinger/skysurvey.org)

An artist’s impression shows how Mars may have looked about four billion years ago. (ESO/M. Kornmesser/N. Risinger/skysurvey.org)

Previous studies have indicated that liquid water once flowed on the Red Planet. Some even suggested that at one time, Mars held great quantities of H2O. But scientists now believe that most of the Planet’s current water supply exists solely in ice or vapor form.

In a recent analysis of data produced by NASA’s Mars Rover Curiosity, researchers at the University of Copenhagen’s Niels Bohr Institute found evidence that there may be salty but liquid water closer to the surface of Mars than previously thought.

Writing in the journal Nature, the researchers said they found the presence of the salt calcium perchlorate in the Martian soil. Salt can lower the freezing point of water so it doesn’t freeze into ice so easily, which is why it’s often used to melt ice on sidewalks and roadways.

Morten Bo Madsen, associate professor and head of the Mars Group at the Niels Bohr Institute, said that under the right conditions the calcium perchlorate can absorb water vapor from the atmosphere.

Measurements he and his colleagues made from Curiosity’s weather monitoring station have indicated that these ‘right conditions’ just happen to occur at night and right after sunrise during winter on Mars.

The researchers believe that Gale Crater was a large lake between 3.5 and 2.7 billion years ago. (NASA/JPL/Caltech/ESA/DLR/MSSS)

The researchers believe that Gale Crater was a large lake between 3.5 and 2.7 billion years ago. (NASA/JPL/Caltech/ESA/DLR/MSSS)

At night, some of Mars’ atmospheric moisture is concentrated into frost on the planet’s surface, much like it does here on Earth.

But when the calcium perchlorate within the Martian soil absorbs the moisture, Madsen said it forms a brine that lowers the freezing point and turns it into a liquid. That liquid water then seeps through and down the porous soil.

“Over time, other salts may also dissolve in the soil. And now that they are liquid, they can move and precipitate elsewhere under the surface,” explained Madsen in a Neil Bohr Institute press release.

Past observations made with Curiosity’s stereo camera showed areas of Mars that had the attributes of an ancient riverbed, indicating that plenty of running water once flowed on the Red Planet.

Some new close-up photos taken by the rover while traveling across Gale Crater on its way to Mount Sharp have revealed swaths of sedimentary deposits that were found lying as ‘plates’ piled atop one another and leaning toward the Martian mountain.

Very fine-grained sediments, which slowly fell down through the water, were deposited right at the bottom of the crater lake. The sediment plates at the bottom are level, which indicates the entire Gale Crater may have once held a large lake. (NASA/JPL, MSSS)

Very fine-grained sediments, which slowly fell down through the water, were deposited right at the bottom of the crater lake. The sediment plates at the bottom are level, which indicates the entire Gale Crater may have once held a large lake. (NASA/JPL, MSSS)

“These kind of deposits are formed when large amounts of water flow down the slopes of the crater and these streams of water meet the stagnant water in the form of a lake. When the stream meets the surface, the solid material carried by the stream falls down and is deposited in the lake just at the lake shore,” said Madsen.

While the sediment layers that the Curiosity observed were found leaning toward Mt. Sharp, the same type of deposits located on the bottom of the crater are level –  something that Madsen said indicates that at one time, the entire Gale Crater may have been a large lake.

While Madsen and his colleagues may have found signs of liquid water on Mars, a key ingredient for life, as we know it, to emerge and survive, they also assert that any potential life forms that might be able to endure the planet’s harsh conditions would probably be wiped out by the Red Planet’s powerful cosmic radiation. Based on that, Madsen and his team said it’s unlikely that life will be found on a planet so cold and dry.

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

Brain Activity May Hasten Death in Cardiac Arrest Patients

Posted April 6th, 2015 at 7:00 pm (UTC-4)
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(Photo: photos.com)

(Photo: photos.com)

A multidisciplinary team of researchers at the University of Michigan has found that when death induced by cardiac arrest is near, the brain bursts into a flurry of activity that may actually play a role in hastening the patient’s death.

It is generally thought that the sudden eruption of signals between the brain and heart may be part of the brain’s efforts to help save the cardiac arrest patient. But in a new study, the research team uncovered surprising evidence that this brain activity, in fact, disrupts heart function.

“Despite the loss of consciousness and absence of signs of life, internally the brain exhibits sustained, organized activity and increased communication with the heart, which one may guess is an effort to save the heart,” said neurologist and senior author Jimo Borjigin, associate professor of molecular and integrative physiology in a University press release.

The research team included investigators with a wide-ranging backgrounds, from engineering, neuroscience, physiology, cardiology, chemistry, to pharmacology. The team examined the biological processes that can lead a healthy heart to stop beating after being deprived of oxygen for a few minutes.

The researchers simultaneously examined the hearts and brains of lab rats who were in cardiac arrest after experimental asphyxiation.

Along with asphyxiation, medical conditions such as cardiac arrhythmias, ischemic stroke, traumatic brain injury, brain hemorrhage and epilepsy can also induce cardiac arrest.

While monitoring the brain and heart activity of rats in cardiac arrest, the researchers noticed an immediate release of a number of neurochemicals from the brain as well as the initiation of heightened brain-heart communication.

An EMS technician performs CPR on a cardiac arrest patient.  Behind patient is an automated external defibrillator (AED) which is also used to help stop ventricular fibrillation (David Bruce Jr./Creative Commons)

An EMS technician performs CPR on a cardiac arrest patient. Behind patient is an automated external defibrillator (AED) which is also used to help stop ventricular fibrillation (David Bruce Jr./Creative Commons)

Using a new device called the electrocardiomatrix, which was developed in Borjigin’s laboratory, researchers noticed that signals from the brain synchronized with the heart rhythm following a steep drop in the heart rate of the lab animals.

But by blocking the flow of the brain’s neurochemicals and communication with the heart, the researchers said that they were able to greatly delay ventricular fibrillation, the most serious cardiac rhythm disturbance.

The lower chambers of the heart simply quiver and are unable to pump any blood during ventricular fibrillation.

“The study suggests that a pharmacological blockade of the brain’s electrical connections to the heart during cardiac arrest may improve the chances of survival in cardiac arrest patients,” said Borjigin.

According to the American Heart Association, brain death and permanent death can begin in just 4-6 minutes after cardiac arrest. A cardiac victim’s chances of survival drop by 7-10 percent with each passing minute without CPR and defibrillation assistance. Few attempts at resuscitation succeed after 10 minutes, according to the American Heart Association.

The study by Borjigin and her team will be published in this week’s PNAS Early Edition.

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

The Best Science Images – March 2015

Posted April 1st, 2015 at 6:41 pm (UTC-4)
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A robot installation is pictured at the booth of Deutsche Telekom at the CeBIT technology on 3/15/15.  The German technology exposition was held in Hanover from 3/16/15-3/20/15 (AFP)

A robot installation is pictured at the booth of Deutsche Telekom at the CeBIT technology fair on March 15, 2015. The German technology exposition was held in Hanover March 16-20, 20/15 (AFP)

A total solar eclipse is visible through the clouds as seen from Vagar on the Faeroe Islands on 3/30/15.  The Faeroe Islands is an archipelago located halfway between Norway and Iceland. (AP)

A total solar eclipse is seen through the clouds from Vagar on the Faeroe Islands on March 30, 2015. The Faeroe Islands is an archipelago located halfway between Norway and Iceland. (AP)

The United Launch Alliance Atlas V rocket with NASA’s Magnetospheric Multiscale (MMS) spacecraft onboard launches from the Cape Canaveral Air Force Station Space Launch Complex 41, 3/12/15.  (NASA)

The United Launch Alliance Atlas V rocket with NASA’s Magnetospheric Multiscale (MMS) spacecraft onboard launches from Cape Canaveral Air Force Station Space Launch Complex 41, March 12, 2015. (NASA)

Here’s an aerial photo, taken on 3/31/15, of some of the solar panels that make up a photovoltaic park in southern France.  Considered to be the biggest solar farm in France, this facility consists of 112,780 solar modules covering an area of 200 hectares of land and representing 100 MW of power.  (Reuters)

An aerial photo, taken on March 31, 2015, shows some of the solar panels that make up a photovoltaic park in southern France. Considered to be the country’s biggest solar farm, this facility consists of 112,780 solar modules covering an area of 200 hectares of land and representing 100 MW of power. (Reuters)

The Solar Impulse-2 takes off from Ahmadabad, India on 3/18/15 as it begins the third leg of its’ historic round-the-world trip. The sun-powered aircraft began its voyage on 3/9/15 in Abu Dhabi, UAE where it is scheduled to return in 8/15 (AP/Press Trust of India)

The Solar Impulse-2 takes off from Ahmadabad, India on March 18, 2015, beginning the third leg of its’ historic round-the-world trip. The sun-powered aircraft began its voyage on March 9, 2015 in Abu Dhabi, UAE, where it is scheduled to return in August of this year. (AP/Press Trust of India)

This is typhoon Maysak as seen from the International Space Station on 3/31/15.  The photo was taken by astronaut Samantha Cristoforetti.  The Pacific Daily News newspaper in Guam reported that the storm has been upgraded to a super typhoon with winds of 241 kph. Officials say super Typhoon Maysak is expected to significantly weaken before reaching the Philippines around Sunday. (NASA/Samantha Cristoforetti)

Typhoon Maysak, as seen from the International Space Station on March 31, 2015, in a photo taken by astronaut Samantha Cristoforetti. The Pacific Daily News newspaper in Guam reported that the storm has been upgraded to a super typhoon with winds of 241 kph. Officials say super Typhoon Maysak is expected to significantly weaken before reaching the Philippines around Sunday. (NASA/Samantha Cristoforetti)

Sunset falls over antennae at the National Radio Astronomy Observatory's Very Large Array, on 3/3/15.  The radio astronomy antenna array is located in Socorro County, New Mexico. (AP)

Sunset falls over antennae at the National Radio Astronomy Observatory’s Very Large Array, on March 3, 2015. The radio astronomy antenna array is located in Socorro County, New Mexico. (AP)

This is a mosaic of images taken by the panoramic camera aboard NASA's Mars Exploration Rover Opportunity shows part of the Red Planet’s "Marathon Valley".  The images that make up this mosaic were taken on 3/13/15, during the 3,958th Martian day, or sol, of Opportunity's work on Mars.  (NASA/JPL-Caltech/Cornell University/Arizona State University)

A mosaic of images taken by the panoramic camera aboard NASA’s Mars Exploration Rover Opportunity shows part of the Red Planet’s “Marathon Valley.” The images that make up this mosaic were taken on March 13, 2015 during the 3,958th Martian day, or sol, of Opportunity’s work on Mars. (NASA/JPL-Caltech/Cornell University/Arizona State University)

A photo of Ceres that was taken by NASA’s Dawn spacecraft on 3/1/15, just a few days before the mission achieved orbit around the previously unexplored dwarf planet to begin a 16-month exploration.  The Dawn spacecraft was about 48,000 kilometers away from Ceres when this photo was taken. (NASA)

This photo of Ceres was taken by NASA’s Dawn spacecraft on March 1, 2015, a few days before the mission achieved orbit around the previously unexplored dwarf planet to begin a 16-month exploration. The Dawn spacecraft was about 48,000 kilometers away from Ceres when this photo was taken. (NASA)

This 3/11/15 file photo shows an array of some of the 2,000 pressure vessels used to convert seawater into fresh water in the Carlsbad Desalination Project’s plant, Carlsbad, Calif.  Considered to be the largest desalination facility in the western hemisphere, it is scheduled to start operations some time later this year and is expected to provide 50 million gallons of fresh drinking water a day.  (AP)

This 3/11/15 file photo shows an array of some of the 2,000 pressure vessels used to convert seawater into fresh water in the Carlsbad (California) Desalination Project’s plant. Considered to be the largest desalination facility in the western hemisphere, it is scheduled to start operations some time later this year and is expected to provide 50 million gallons of fresh drinking water a day. (AP)

Researchers in a study released on 3/13/15 have successfully identified what they are calling a "treasure chest" of ancient galaxy clusters. This map of the entire sky was captured by the European Space Agency's Planck mission. The band running through the middle corresponds to dust in our Milky Way galaxy. The black dots indicate the location of galaxy cluster candidates identified by Planck and subsequently observed by the European Space Agency's Herschel mission.  (ESA/Planck Collaboration/ H. Dole, D. Guéry & G. Hurier, IAS/University Paris-Sud/CNRS/CNES)

In a study released on March 13, 2015, researchers successfully identified what they call a “treasure chest” of ancient galaxy clusters. This map of the entire sky was captured by the European Space Agency’s Planck mission. The band running through the middle corresponds to dust in our Milky Way galaxy. The black dots indicate the location of galaxy cluster candidates identified by Planck and subsequently observed by the European Space Agency’s Herschel mission. (ESA/Planck Collaboration/ H. Dole, D. Guéry & G. Hurier, IAS/University Paris-Sud/CNRS/CNES)

A Soyuz spacecraft carrying a new crew to the International Space Station, blasts off from Baikonur cosmodrome, Kazakhstan on 3/28/15.  The Russian rocket carries U.S. astronaut Scott Kelly, Russian cosmonauts Gennady Padalka, and Mikhail Korniyenko. (AP)

A Soyuz spacecraft carrying a new crew to the International Space Station, blasts off from Baikonur cosmodrome, Kazakhstan on March 28, 2015. The Russian rocket carries U.S. astronaut Scott Kelly, Russian cosmonauts Gennady Padalka, and Mikhail Korniyenko. (AP)

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

Mercury’s Surface ‘Painted’ With Carbon from Comets

Posted March 30th, 2015 at 2:39 pm (UTC-4)
1 comment

Planet Mercury from image data by NASA's MESSENGER spacecraft. (NASA/JHU Applied Physics Lab/Carnegie Inst)

Mercury from image data by NASA’s MESSENGER spacecraft. (NASA/JHU Applied Physics Lab/Carnegie Inst)

A first glance, the planet Mercury looks a lot like our Moon, both gray and pockmarked with craters after being bombarded with meteorites and blasted by the solar wind over the millennia.  Some take the similarity further, referring to them as “twins.”

The color of Mercury’s surface though is much darker than the moon, so much so that scientists consider it to be the least reflective of all the planets in our solar system.   It’s nearest neighboring planet, Venus, on the other hand, is considered the brightest and most reflective of our planetary neighbors.

Now a group of scientists say that new research they’ve conducted may have solved the long-standing mystery of Mercury’s dark, dull finish.

Writing in the latest edition of the journal, Nature Geoscience, the scientists said their studies suggest that a steady dusting of carbon released by passing comets over billions of years has slowly painted Mercury’s surface black.

“Our study answers a longstanding mystery about why Mercury’s surface is darker than the moon’s surface, by implicating carbon as a “stealth” darkening agent, which is difficult to detect with available remote sensing methods,” said lead author Megan Bruck Syal, a postdoctoral researcher at Lawrence Livermore National Laboratory in a press release. “Mercury is effectively painted black by the constant influx of carbon-rich micrometeorites.”

Impact material generated without the presence of carbon from complex organics, top left, is lighter than material generated with carbon, top right. Scanning electron microscope images, bottom row, show finer-scale structure and texture variations. Images: (NASA/Ames/Brown University)

Impact material generated without the presence of carbon from complex organics, top left, is lighter than material generated with carbon, top right. Scanning electron microscope images, bottom row, show finer-scale structure and texture variations. Images: (NASA/Ames/Brown University)

Since comets often break apart as they get close to the sun, Mercury a mere 57,910,000 km away, receives a steady barrage of cometary dust, which is about 25 percent carbon by weight, from these crumbling celestial bodies.

So, the researchers developed and used a computer model to estimate just how much of the cometary dust that hit Mercury actually stuck to the planet’s surface versus the amount that bounced back into space.

Calculations made from the model suggested that Mercury’s surface should be between 3 to 6 percent carbon after billions of years collecting cometary dust.

The researchers then needed to determine just how dark Mercury’s surface would be after being coated by so much cometary carbon over such a long period of time.

Using a 4 meter cannon at NASA’s Ames Vertical Gun Range the researchers shot projectiles that were surrounded by sugar, which mimicked the organic material found in comets, into a target substance that simulated lunar basalt.

“We used the lunar basalt model because we wanted to start with something dark already and see if we could darken it further,” said Peter Schultz, professor emeritus of geological sciences at Brown University and a co-author of the new research.

The heat produced by the cannon blast burned up the sugar and released carbon which became deeply embedded into the target material that melted from the impact of the projectile.

The researchers found that amount of light reflected by the target material, after the cannon shot, was decreased to a level of less than five percent, which is also about the same amount of light reflected by the darkest areas of Mercury.

After conducting a spectroscopic analysis of impact material samples from the cannon shots the researchers didn’t find any distinctive spectral fingerprints just like the spectral signatures from Mercury.

“We show that carbon acts like a stealth darkening agent,” Schultz said. “From the standpoint of spectral analysis, it’s like an invisible paint.”

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.