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.

60 Billion Earth-like Planets Could Exist in Milky Way Galaxy

Posted July 2nd, 2013 at 7:21 pm (UTC+0)
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A planet with clouds and surface water orbits a red dwarf star in this artist’s conception of the Gliese 581 star system. (Illustration: Lynette Cook)

A planet with clouds and surface water orbits a red dwarf star in this artist’s conception of the Gliese 581 star system. (Illustration: Lynette Cook)

A new study finds there could be about 60 billion Earth-sized habitable planets orbiting red dwarfs – the most common stars in our universe – in the Milky Way galaxy.

That’s more than twice as many potentially habitable planets than was previously thought.

The new report from two Chicago area universities finds that clouds surrounding these planets may be hiding them from detection.

The researchers drew upon current data from NASA’s Kepler Mission, which searched for Earth-like planets orbiting other stars up until this past May.  The new study from Northwestern University and the University of Chicago suggests there is approximately one Earth-size planet in the habitable zone of each red dwarf.

“Most of the planets in the Milky Way orbit red dwarfs,” said Nicolas Cowan, a postdoctoral fellow at Northwestern University. “A thermostat that makes such planets more clement means we don’t have to look as far to find a habitable planet.”

The findings contradict other recent studies, including one  from the Harvard-Smithsonian Center for Astrophysics, which found our galaxy  has about 4.5 billion Earth-sized planets. Another study from the California Institute of Technology (Caltech) estimated  there are about 30 billion of these planets in our galaxy.

“Those numbers are confusing, partially because they are still being sorted out,” Cowan said in an email to Science World.

All three studies were based on virtually the same data from Kepler.

While the Harvard-Smithsonian and Caltech studies each used 1D modeling to reach their findings, the Chicago area based study used a 3D model.

“Our 3D calculations of the HZ [Habitable Zone] move its inner edge much closer to the star,” said Cowan. “The Kepler planetary demographics tell us how many planets orbit at what distance from their host star. We therefore know that our revision to the HZ accommodates roughly twice as many planets.”

This illustration shows simulated cloud coverage (white) on a tidally locked planet (blue) that would be orbiting a red dwarf star. (Illustration by Jun Yang)

This illustration shows simulated cloud coverage (white) on a tidally locked planet (blue) that would be orbiting a red dwarf star. (Illustration by Jun Yang)

For decades, scientists have said that a star’s habitable zone is an area where planets can orbit their star while still being able to retain liquid water at their surfaces. But the researchers say that formula doesn’t take clouds, which have a major climatic influence, into consideration.

“Clouds cause warming, and they cause cooling on Earth,” said Dorian Abbot, an assistant professor in geophysical sciences the University of Chicago and member of the research team. “They reflect sunlight to cool things off, and they absorb infrared radiation from the surface to make a greenhouse effect. That’s part of what keeps the planet warm enough to sustain life.”

According to the team’s research, in order for a planet to be maintain liquid water it would need to complete an orbit around its star about once a year, just as Earth orbits the sun.

But, “if you’re orbiting around a low mass or dwarf star, you have to orbit about once a month, once every two months to receive the same amount of sunlight that we receive from the sun,” Cowan said.

Since these planets would maintain such tight orbits, they would sooner or later become “tidally locked with their sun,” with the same side of the planet are always facing their suns, similar to how the moon orbits around Earth.  According to computations made by the Chicago area team, the sun would always be directly above the planet, “at high noon.”

If astronomers find that tidally locked planets have no substantial cloud cover,  they will measure the highest temperatures of the planet when its dayside faces their telescopes. When that planet continues its orbit around its star and shows its dark side to the telescope, temperatures would reach their lowest point.

But if the exoplanet has highly reflective clouds dominating its dayside, they would block much of the infrared radiation from its surface.

“You would measure the coldest temperatures when the planet is on the opposite side, and you would measure the warmest temperatures when you are looking at the night side, because there you are actually looking at the surface rather than these high clouds,” said Jun Yang, a member of the research team from the University of Chicago.

Earth's climate is greatly affected by clouds. Chicago Area researchers say that if clouds only cooled the planet by reflecting solar energy back into space, Earth would completely ice over. But if clouds only warmed the planet by absorbing and reemitting infrared energy back to the surface, Earth would fry under a runaway greenhouse effect like the one on Venus. (Norman Kuring/NASA GSFC)

Earth’s climate is greatly affected by clouds. (NASA)

Previous efforts to simulate an exoplanet habitable zone’s inner edge were used one-dimensional calculations and mostly ignored clouds, said the Chicago researchers. Their work instead focused on charting how temperature decreases with altitude.

For the first time, by using three-dimensional global calculations, the research team was able to find the effect of water clouds on the inner edge of the habitable zone. The team used simulations similar to those used to predict Earth’s climate.

“There’s no way you can do clouds properly in one-dimension,” Cowan said. “But in a three-dimensional model, you’re actually simulating the way air moves and the way moisture moves through the entire atmosphere of the planet.”

The research team anticipates the forthcoming James Webb Space Telescope will verify its findings.  If the new telescope, which NASA hopes will launch in 2018, detects a signal from an exoplanet,  “it’s almost definitely from clouds, and it’s a confirmation that you do have surface liquid water,” said Abbot.

IRIS: New NASA Spacecraft to Study Mysterious Region of Sun’s Atmosphere

Posted June 28th, 2013 at 8:25 pm (UTC+0)
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NASA's Interface Region Imaging Spectrograph (IRIS) with solar panels open in flight position, in the clean room at the Lockheed Martin Advanced Technology Center in Palo Alto, where it was designed and built. (LMSAL)

NASA’s Interface Region Imaging Spectrograph (IRIS) with solar panels open in flight position, in the clean room at the Lockheed Martin Advanced Technology Center in Palo Alto, where it was designed and built. (LMSAL)

Did you know that the Sun’s outer atmosphere, or corona, is much hotter than its surface? Scientists have been quite curious about a mysterious interface region of the Sun’s atmosphere that amplifies energy from about 5,800 degrees Kelvin on the surface, or photosphere, to around 1,000,000 degrees Kelvin in the corona.

With Thursday’s launch of its Interface Region Imaging Spectrograph or IRIS spacecraft, NASA is planning to find out just how solar matter moves, gathers energy and heats up as it passes through the Sun’s chromosphere, it’s solar transition region, and into the corona that powers the solar wind.

According to NASA, most of the sun’s ultraviolet radiation, which they say has an impact on Earth’s climate, is also produced in this interface region.

This image from Japan Aerospace Exploration Agency’s (JAXA) Hinode mission shows the lower regions of the sun’s atmosphere, the interface region, which the Interface Region Imaging Spectrograph, or IRIS, will study in detail. (Photo: JAXA/Hinode)

This image from Japan Aerospace Exploration Agency’s (JAXA) Hinode mission shows the lower regions of the sun’s atmosphere, the interface region, which the Interface Region Imaging Spectrograph, or IRIS, will study in detail. (Photo: JAXA/Hinode)

“We are thrilled to add IRIS to the suite of NASA missions studying the sun,” said John Grunsfeld, NASA’s associate administrator for science in Washington. “IRIS will help scientists understand the mysterious and energetic interface between the surface and corona of the sun.”

At 6:30PM Thursday, an Orbital L-1011 carrier aircraft, with the Pegasus XL rocket and its IRIS spacecraft payload strapped beneath, it took off from California’s Vandenberg Air Force base to a release site over the Pacific Ocean.

Five seconds after being dropped by the plane, the first stage of the Pegasus XL ignited and carried IRIS into space. NASA officials said that the IRIS spacecraft successfully separated from its launch rocket’s third stage at 7:40 PM PDT.  Twenty-five minutes later, at 8:05 PM PDT, the IRIS team received confirmation that the spacecraft successfully deployed its solar arrays (seen in the top photo), had power, acquired its target, the sun, and that all systems were operating as expected.

NASA Video of the release and launch of the Pegasus XL from its Orbital L-1011 carrier aircraft

NASA says the IRIS is now going through what it calls a 60-day commissioning phase to make sure the spacecraft and its onboard instruments are functioning properly.

Mission leaders say that they are centering IRIS’ science investigation on three main themes.

The Sun's corona, or atmosphere, taken with a special camera that blocks out light from the Sun's main disk. (ESA/NASA/SOHO)

The Sun’s corona, or atmosphere, taken with a special camera that blocks out light from the Sun’s main disk. (ESA/NASA/SOHO)

1. Which types of non-thermal energy dominate in the Sun’s chromosphere and beyond?

2. How does the chromosphere regulate mass and energy supply the corona and heliosphere, which NASA says is the giant magnetic bubble that extends way beyond the orbit of Pluto and contains our solar system, the solar wind, and the entire solar magnetic field?

3. How do magnetic flux, the flow of magnetic energy, and matter rise through the lower atmosphere, and what role does flux emergence play in flares and mass ejections?

According to NASA, the IRIS spacecraft, which weighs 167 Kilograms, is 2.1 meters long and 3.7 meters across, was designed by the Smithsonian Astrophysical Observatory headquartered at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.

After its launch, IRIS was placed in a sun-synchronous polar orbit where it will circle over the north and south poles and pass over the same part of Earth at about the same time of day.  This unique orbit will allow the IRIS mission team to make almost continuous solar observations during its planned two-year mission.

Study: Diet Changes May Have Been Crucial Step in Becoming Human

Posted June 25th, 2013 at 7:27 pm (UTC+0)
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Artist Illustration of Paranthropus hominid in southern Africa 1 million years ago. (Artwork by Walter Voigt -provided by Lee Berger and Brett Hilton-Barber)

Illustration of Paranthropus hominid in southern Africa one million years ago. (Artwork by Walter Voigt -provided by Lee Berger and Brett Hilton-Barber)

A change in  diet about 3.5 million years ago  may have  set hominid species on a path to becoming  human, according to a study led by the University of Colorado, Boulder.

Scientists conducted high-tech tests on the tooth enamel found in  remains of ancient hominid species. The results indicated that, prior to that dietary change, the hominids ate pretty much like chimpanzees, dining on items like fruits and some leaves.

But then some hominid species started adding  grasses and flowering plants to their daily menus.

Grasses and sedges were readily available back then, but the hominids seem to have ignored them for an extended period, said anthropology Professor Matt Sponheimer, lead author of the study.

“We don’t know exactly what happened,” said Sponheimer. “But we do know that after about 3.5 million years ago, some of these hominids started to eat things that they did not eat before, and it is quite possible that these changes in diet were an important step in becoming human.”

A field of grass-like sedge in Hamerkop Kloof, Magaliesberg, South Africa (Wikimedia Commons)

A field of grass-like sedge in Hamerkop Kloof, Magaliesberg, South Africa (Wikimedia Commons)

Scientists had previously analyzed the teeth of  about 87 ancient hominid specimens.  Sponheimer and his team came up with new detailed information on the teeth of 88 additional specimens, which also included five previously unanalyzed hominid species.

To find out what kind of plants these early hominids ate, Sponheimer’s team analyzed the carbon isotopes found on the fossilized teeth.  The researchers found the carbon signals of two distinct plant groups; the first, called C3, came from plants like trees and bushes, while the other,  called C4, came from plants like grasses and sedges, which are flowering grasses.

The researchers also examined the microscopic wear of hominid teeth, which provided scientists with more information on the foods they were eating. Since there were multiple species of hominids, there was no such thing as one specific hominid diet.

The skull of Paranthropus boisei photographed at the Nairobi National Museum (Bjørn Christian Tørrissen via Wikimedia Commons))

The skull of Paranthropus boisei photographed at the Nairobi National Museum (Bjørn Christian Tørrissen via Wikimedia Commons)

While early ancestors in the genus Homo, which includes modern humans and the 3 million-year-old fossil known as Lucy – who many scientists see as the matriarch of today’s humans – were diversifying their diets with different food choices, another type of short, upright hominid, the Paranthropus boisei, who also lived in Eastern Africa at the time, was moving toward a much more specific diet made up mostly of items like the grasses.

Scientists had given the P. boisei hominids the nickname “Nutcracker Man” because it had large, flat teeth and powerful jaws that may have been powerful enough to crack nuts.  But, according to Sponheimer, more recent analyses suggest  they might have actually used their back teeth to grind grasses and sedges.

“We now have the first direct evidence that, as the cheek teeth on hominids got bigger, their consumption of plants like grasses and sedges increased,” he said. “We also see niche differentiation between Homo and Paranthropus. It looks probable that Paranthropus boisei had a relatively restricted diet, while members of the genus Homo were eating a wider variety of things. The genus Paranthropus went extinct about one million years ago, while the genus Homo, that includes us, obviously did not.”

Researchers are  puzzled at the differences in the evolution of those hominids living in eastern Africa compared to those from southern Africa.

Another hominid, called Paranthropus robustus, which was found in southern Africa was very anatomically similar its eastern African cousin, P. boisei.  But Sponheimer and his team found that the teeth of the two had quite different carbon isotopic compositions in their teeth, which suggested that they each ate different diets.

Another artist representation of Paranthropus in southern Africa more than 1 million years ago. (Courtesy ArchaeologyInfo.com/ScottBjelland)

Artist representation of Paranthropus in southern Africa more than one million years ago. (Courtesy ArchaeologyInfo.com/ScottBjelland)

The southern African P. robustus hominid appeared to have augmented its diet of grasses and sedges with items from the C3 group such as trees and bushes.

“This has probably been one of the biggest surprises to us so far,” said Sponheimer. “We had generally assumed that the Paranthropus species were just variants on the same ecological theme, and that their diets would probably not differ more than those of two closely related monkeys in the same forest.

But the researchers found that their isotopic evidence of each of the hominids indicated that their diets were so different from each other that they could have been as different as primate diets can be.

“Ancient fossils don’t always reveal what we think they will. The upside of this disconnect is that it can teach us a great deal, including the need for caution in making pronouncements about the diets of long-dead critters,” said Sponheimer.

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