What the work means for the carbon balance of the Earth is also not as obvious as it may seem.
or long-lived wood products to keep the carbon from the atmosphere, and then replanting with species that are suited slightly more to the changing climate."
which in 1980 became the first disease to be officially wiped out from the planet. The global polio initiative, a mammoth programme involving the vaccination of billions of children,
and corals will produce less calcium carbonate as the amount of CO2 in the atmosphere rises,
whether the Earth's skies are dimming or brightening, how this affects the amount of sunlight reaching the planet's surface and what that means for climate change.
Two studies published in Science in 2005 concluded that a global dimming trend that began in the 1950s has been replaced since 1990 by global brightening1,
2. The likely effect of all that extra solar radiation reaching the Earth's surface would be faster global warming.
which help to reflect the Sun's rays back into space and so cool the planet.
Aerosols can also reduce cloudiness, however, as probably happens in northern China, meaning that the net effect of aerosol pollution on global temperatures is worryingly uncertain.
tends to absorb sunlight rather than scattering it back into space. This means that it warms the troposphere in much the same way as carbon dioxide and other greenhouse gases.
which measured incoming solar radiation rather than visibility, concluded that the skies have brightened over most land areas,
some bacteria not only survive in the upper atmosphere but might affect weather and climate, according to a study published on 28 january in the Proceedings of the National Academy of Sciences1.
researchers analysed air samples from a six-week hurricane-research mission by NASA in 2010.
bacteria accounted for around 20%of all particles#biological and non-biological#a higher proportion than in the near-Earth atmosphere."
Genetic analysis revealed that some microbes in the upper atmosphere are thought related to bacteria to catalyse ice-crystal formation and cloud condensation2.
especially in the upper atmosphere where dust is relatively rare, could influence weather and climate3, says study co-author Athanasios Nenes, an atmospheric scientist at the Georgia Institute of technology."
Samples collected by the NASA mission before, during, and after two hurricanes also allowed researchers to study the effects of extreme weather on the atmospheric microbiome.
#Solar magnetism twists braids of superheated gas Geoff Brumfiel hears from researcher Jonathan Cirtain why the Sun s atmosphere is hotter than its surface.
For decades, researchers have suspected that powerful magnetic fields are heating the corona. The Sun's atmosphere is just jam-packed full of magnetic field,
says Cirtain. As the lines of those fields cross and twirl, the theory went, they push and pull the charged gas in the corona, giving it the energy that heats it up.
The problem is that nobody has been able to see the magnetic fields in close up until now. Cirtain and his team have developed the High-resolution Coronal Imager (Hi-C
a camera capable of taking pictures of the Sun's corona in fine detail. The imager was placed on board a research rocket at the White sands Missile Range in New mexico
and flown to the edge of space. It took several minutes to fall to Earth, during which time it took a series of pictures of the Sun (see video).
A team member started analysing the data on the drive back from the missile range, and immediately saw evidence of braids in the twists of coronal gas.
We slammed on the brakes and swerved off to the side of the road, says Cirtain.
The group now hopes to put the Hi-C on a next-generation spacecraft that will monitor the Sun for longer periods of time e
) Meanwhile, the Japanese space agency JAXA will get#22.9#billion to refurbish its facilities and to speed up development of ALOS-2,
a satellite that will monitor natural disasters and measure atmospheric carbon dioxide levels. The extra cash will keep it on schedule for launch before April next year.
when it helped with the initial design of K-STAR, believes that the K-DEMO project is feasible,
Gisele Azimi and Adam T. Paxsona thin film made of a water-repelling ceramic material#here a rare-earth oxide#can help you stay dry.
Exposed to the sun, a solar cell employing such nanowires can turn nearly 14 percent of the incoming light into electricity#a new record that opens up more possibilities for cheap and effective solar power.
and phosphorus that absorbs much of the light from the sun (a property known as its band gap).
At the same time the novel cells could be built into so-called multijunction solar cells#compound devices that incorporate several different types of semiconductor material in layers like a sandwich to absorb as much of the energy in sunlight as possible.
Such multijunction cells have converted more than 43 percent of the energy in sunlight into electricity#currently
but they can be made cheaper by combining them with low-cost lenses to concentrate the sunlight onto smaller versions of the cells.
Or maybe it s a devious scheme predicated on boring a hole into the depths of the planet with the world s hardest drill bit.
"We still need really superhard materials to explore deeper and deeper into Earth s interior,
Had one of these started running at the Big bang and continued up to the present, it would have lost
#Nearby star is almost as old as the Universe Astronomers have discovered a Methuselah of stars#a denizen of the Solar system's neighbourhood that is at least 13.2 billion years old and formed shortly after the Big bang."
"We believe this star is known the oldest in the Universe with a well determined age,
says Howard Bond, an astronomer at Pennsylvania State university in University Park, who announced the finding on 10 january at a meeting of the American Astronomical Society in Long beach, California1.
The venerable star, dubbed HD 140283, lies at a comparatively short distance of 190 light years from the Solar system
and has been studied by astronomers for more than a century. Researchers have known long that the object consists almost entirely of hydrogen
and helium#a hallmark of having formed early in the history of the Universe, before successive generations of stars had a chance to forge heavier elements.
But no one knew exactly how old it was. Determining the star s age required several steps.
First, Bond and his team made a new and more accurate determination of the star s distance from the Solar system,
using 11 sets of observations recorded between 2003 and 2011 using the Hubble space telescope s Fine Guidance Sensors,
which measure the position of target stars relative to reference stars. The astronomers also measured the brightness of the star as it appears in the sky,
and were then able to calculate its intrinsic luminosity. The team then exploited the fact that HD 140283 is in a phase of its life cycle in
which it is exhausting the hydrogen at its core. In this phase, the star's slowly dimming luminosity is a highly sensitive indicator of its age,
says Bond. His team calculates that the star is 13.9 billion years old, give or take 700 million years.
Taking into account that experimental error, the age does not conflict with the age of the Universe, 13.77 billion years.
The star's age is therefore at least 13.2 billion years #which was estimated the age of another known Methuselah2#and possibly older.
Its age is known with considerably better confidence than that of the previous Methuselah says Bond.
The discovery places constraints on early star formation, says Volker Bromm, an astronomer at the University of Texas at Austin.
The very first generation of stars coalesced from primordial gas, which did not contain appreciable amounts of elements heavier than helium,
but non-zero abundance of heavy elements#shows that the star must have formed after the first stellar generation.
Conditions for making the second generation of stars, then, "must have been in place very early, says Bromm.
The very first stars are thought usually to have coalesced a few hundred million years after the Big bang,
But before the second generation of stars could form, that gas had to cool down. The early age of the second-generation star HD 140283 hints that the cooling time,
#Meteorite carries ancient water from Mars It may just look like your average rock, but in fact it's an extra-special delivery from the red planet.
Laboratory analysis has revealed that a specimen bought from a Moroccan meteorite dealer in 2011 is the first sample of Martian origin that is similar to the water-rich rocks examined by NASA s rovers.
The meteorite, dubbed Northwest Africa (NWA) 7034, contains a concentration of water by weight about ten times higher than in any of the other 100
or so known Martian meteorites#those rare rocks that get ejected from the Martian surface into space when an asteroid hits the planet,
and eventually find their way to Earth. It s also the only known Martian sample On earth that hails from a critical period, about 2 billion years ago,
when Mars is thought to have become colder and drier than it was originally. Carl Agee of the University of New mexico in Albuquerque and his colleagues report their findings from samples of the meteorite in Science online today1."
"Agee and his collaborators have thrown open the door to a whole new part of Mars, says planetary scientist Munir Humayun at Florida State university in Tallahassee,
who was involved not in the study. The meteorite, he adds, is"the first of a new class of Martian meteorites that provides more direct clues to the surface history of Mars. Moreover,
Humayun says, NWA 7034 may provide the only direct corroboration for the rovers observations for some time to come,
as the fate of a long-delayed mission to bring samples of Mars back to Earth is still uncertain.
Carl Ageethe rock found in the Sahara desert, has a higher water content than any Martian meteorite previously analysed.
The elemental composition of the meteorite strongly resembles that of rocks examined in 2005 by NASA s Spirit rover at Gusev Crater2.
Those rocks showed evidence of chemical alteration by interactions with liquid water, notes Agee. The composition of NWA 7034 also matches that of rocks studied by Curiosity, NASA s newest rover,
as described in preliminary reports from members of that mission. Dating from 2. 1 billion years ago,
NWA 7034 is the second-oldest Martian meteorite, and provides a missing link in the planet s geological record,
according to Agee. The oldest prospective Martian meteorite, ALH 84001, is 4. 5 billion years old,
whereas all other Martian meteorites are 1. 3 billion years old or younger.)Several lines of evidence indicate that parts of Mars were warmer and wetter,
and therefore a possible haven for carbon-based life, some 4 billion years ago. The relatively high water content of NWA 7034,
which could be as much as 0. 6%by weight, suggests that"crustal or surface processes involving water may have lasted well beyond the 4-billion-year mark,
Agee adds. That is not a surprise, given the map of hydrogen (a stand-in for water) generated by an instrument on the Mars Odyssey orbiting spacecraft and the presence of small amounts of water in younger Martian meteorites
notes Harry Mcsween at the University of Tennessee in Knoxville. The meteorite is made of volcanic rock,
and the presence of water in it suggests that crustal rocks on Mars interacted with surface water that was delivered by volcanic activity,
near-surface reservoirs or by impacting comets, Agee says. But Jeffrey Taylor of the University of Hawaii in Honolulu says that
whether that water content truly reveals an abundance of surface water on Mars 2. 1 billion years ago awaits further study u
#Quantum gas goes below absolute zero It may sound less likely than hell freezing over, but physicists have created an atomic gas with a sub-absolute-zero temperature for the first time1.
Their technique opens the door to generating negative-Kelvin materials and new quantum devices, and it could even help to solve a cosmological mystery.
whereas clouds of atoms would normally be pulled downwards by gravity, if part of the cloud is at a negative absolute temperature,
Another peculiarity of the sub-absolute-zero gas is that it mimics'dark energy''the mysterious force that pushes the Universe to expand at an ever-faster rate against the inward pull of gravity.
Schneider notes that the attractive atoms in the gas produced by the team also want to collapse inwards,
"It s interesting that this weird feature pops up in the Universe and also in the lab,
"This may be something that cosmologists should look at more closely o
#Memory molecule dethroned For years, a particular protein has been cast as a lynchpin of long-term memory.
#Ephemeral third ring of radiation makes appearance around Earth First discovered in 1958, the Van allen belts have been thought to comprise two reservoirs of high-speed,
electrically charged particles, corralled into separate doughnut-shaped rings by Earth s magnetic field. The outer ring orbits at a distance of some 10,000-60,000 kilometres above Earth,
and encircles an inner band of even more energetic particles, roughly 100-10,000 kilometres above Earth.
That s the configuration the belts were in when James Van allen first spotted them using satellite data half a century ago,
and that s also the structure that NASA s twin Van allen Probes recorded when they began operation on 1 september 2012.
But just two days later, telescopes on the probes revealed the emergence of an additional,
however, and Baker and his team now attributes its creation to an interplanetary shock wave#a travelling outburst of solar-wind particles from the Sun#that has been detected by other craft.
NASATHE two Van allen Probes orbit through the radiation belts that surround Earth, shown in cross section in this artist's impression.
either escaping into the atmosphere or reacting with the alkali and slowing down the methanol-hydrogen conversion.
parallel universe of unexplored RNAS, says Nikolaus Rajewsky, the lead author of one of the studies and a systems biologist at the Max Delbr#ck Center for Molecular Medicine in Berlin.
and her colleagues sent the first missive from the circular universe. They reported finding a plethora of circular human RNAS
#Moon-size exoplanet circling sun-like star smallest yet A newfound world called Kepler 37 b could easily blend in to the long and growing list of known extrasolar planets,
But the new addition to the catalogue of 800-plus exoplanets stands out in at least one major respect#it is far smaller than any planet yet discovered outside of our solar system.
In fact, it is just a shade larger than Earth s moon.""What makes this very interesting is this is a planet smaller than anything we see in our own inner solar system,
says Thomas Barclay, a research scientist at the NASA AMES RESEARCH CENTER in Moffett Field, Calif. Barclay is lead author of a study published online February 20 in Nature announcing the discovery of Kepler 37 b and two slightly larger worlds in the same planetary system.
Scientific American is part of Nature Publishing Group. The researchers used NASA s Kepler space telescope to identify the three planets orbiting Kepler 37, a star some 200 light-years away that is somewhat smaller than the sun. The spacecraft monitors more than 150,000 stars in the Milky way
for occasional winks, or dips in brightness, that might be caused by a planet passing in front of its star, from the probe s perspective.
The Kepler mission has discovered already more than 100 new planets since its launch in 2009 and has identified thousands of additional candidates that await confirmation.
Planets smaller than Earth block relatively small amounts of starlight which limits astronomers ability to detect them with Kepler.
But the star Kepler 37 is bright and relatively free of disturbances, such as starspots, that can obscure a faint planetary signal.
By observing the planet Kepler 37 b as it transited, or passed in front of its star, more than 50 times,
Barclay and his colleague drew out a subtle but recurrent pattern. Every 13 days or so the star dimmed by a tiny fraction#just 0. 002 percent#as the tiny planet passed across the star s face.
The exoplanet that previously held the record on the tiny end of the size spectrum#a Mars-size object known as Kepler 42 d#is nearly twice the diameter of Kepler 37 b. The newfound body is just 80 percent
Mercury s diameter and 30 percent that of Earth. Kepler measures the diameters and orbital properties of exoplanets but is usually unable to pinpoint their masses.)
All three of the exoplanets found by Barclay and his colleagues, in fact, will rank among the smallest known:
Kepler 37 c is 74 percent the diameter of Earth, and Kepler 37 d is roughly twice our planet s diameter.
Orbiting its star at one tenth the distance between Earth and the sun, tiny Kepler 37 b must be extremely hot."
"Any water on the surface would disappear very quickly, Barclay says.""There is almost no chance of an atmosphere or liquid on the surface.
The researchers predict that Kepler 37 b would be a barren, rocky world similar to Mercury.
The larger worlds in the planetary system orbit somewhat farther out but would still suffer scorching heat from the star.
All three planets keep closer to the star Kepler 37 than any planet orbits the sun."It just shows that Kepler has just an extraordinary ability to see a wide diversity of planetary architectures,
says Greg Laughlin, a professor of astronomy and astrophysics at the University of California, Santa cruz, who did not contribute to the new study.
Kepler was built to search for exo-Earths#rocky planets in cooler orbits than the uninhabitable worlds of the Kepler 37 system.
But in the meantime it has found numerous planetary systems that little resemble ours.""What Kepler is also showing,
and this is a side dividend to the main mission, is that the galactic planetary census is a lot different than we had believed from looking at our own planetary system,
Laughlin says.""Our solar system just contains nothing whatsoever inside Mercury s orbit. But it turns out that the average planetary system has a lot going on in the inner region.
More from Scientific American. There is one catch in Kepler s search for worlds comparable with or smaller than Earth:
Whereas giant Jupiter-size planets often exert a gravitational tug on their host stars that is detectable with Earth-based telescope spectrographs,
smaller exoplanet discoveries have proved difficult to confirm with observations other than Kepler s . So researchers have turned to statistical arguments
instead to quantify the probability of a false positive#for instance, a pair of undetected binary stars whose regular eclipses mimic a planetary signal.
Barclay and his colleagues used computer modeling to identify potential false positives and then rule them out with additional observations from the ground.
In the end, based on population estimates of exoplanets binary stars and other astronomical objects, the researchers calculated the probability that the signal collected from Kepler represents a true planet."
"In this case, with the innermost planet we are confident that it is a true planet orbiting the target star with a confidence of 99.95 percent,
Barclay says.""So we re very confident that this is what we think it is
#FDA Approves First Retinal implant An article by Scientific American. The Food and Drug Administration (FDA) Thursday approved the first retinal implant for use in the United states. The FDA s green light for Second sight s Argus II Retinal Prosthesis System gives hope to those blinded
by a rare genetic eye condition called advanced retinitis pigmentosa, which damages the light-sensitive cells that line the retina.
#Computer program roots out ancestors of modern tongues In Fiji, a star is a kalokalo. For the Pazeh people of Taiwan, it is mintol,
Such things have included everything from spare parts for the International space station above to the beef on our dinner plates to the organs inside our bodies.
#Planck snaps infant Universe For astronomers, it is the ultimate treasure map. On 21 march, the Planck space telescope team released the highest-precision map yet of the cosmic microwave background (CMB),
the faint but ubiquitous afterglow of the Big bang. Crowning nearly 50 years of CMB study,
the map records the precise contours of the nascent Universe #and in doing so pins down key parameters of the Universe today.
The tiny fluctuations embedded in the CMB map reveal a Universe that is expanding slightly more slowly than had been thought.
That dials back the amount of gravity-countering dark energy to 68.3%of the Universe and adds a little more unseen dark matter to the mix.
It also means that the Universe is a little older: 13.82 billion years old, adding a few tens of millions of years to the previously calculated value.
The map even shows that the number of neutrino flavours permeating the cosmos will probably remain at three#had there been a fourth,
the Universe would have expanded more quickly during its first moments. These results represent refinements of numbers obtained by previous missions such as the Wilkinson Microwave Anisotropy Probe (WMAP.
Where the Planck spacecraft, watching the sky from a vantage point 1. 5#million kilometres away,
breaks the most new ground is in its support for the reigning theory that describes the instant after the Big bang. The theory, known as inflation,
holds that during an unimaginably rapid expansion lasting just 10##32#seconds or so, the Universe grew from a subatomic point to something the size of a grapefruit that then continued to expand at a more stately pace.
This growth spurt would help to explain why the Universe we see today is homogeneous on the largest scales
yet riddled with clumps, filaments and sheets of galaxies.""Planck could have found that there was something majorly wrong with inflation,
says astrophysicist Jo Dunkley at the University of Oxford, UK, who has worked on data from Planck and the WMAP."
"Instead, we ve got new evidence that this expansion did happen. In the minutes that followed the burst of inflation,
particles such as protons and electrons formed from the cauldron of proto-matter, and photons began to bounce around like pinballs.
It was only 380,000#years later, when the charged plasma cooled into neutral atoms, that those photons could fly freely.
and carry with them an imprint of the quantum fluctuations that roiled the inflationary Universe. Seen in the map as tiny variations around an average temperature of 2. 7 kelvins
which ultimately snowballed into the galaxies seen today.""All the structures we see in the Universe are coming from these little perturbations,
says Paul Shellard, a Planck cosmologist at the University of Cambridge, UK. SLIDESHOW: Homing in on the cosmic microwave background In 1965,
Arno Penzias and Robert Wilson discovered the cosmic microwave background. Their giant but crude microwave receiver saw the radiation as being the same in all directions,
occurring at 2. 7 kelvin. NASA/WMAP SCIENCE TEAMIT was not until the launch of the Cosmic Background Explorer (COBE) spacecraft that astronomers could begin to see variations in the background, at levels of 1 part in 100,000.
NASATHE Wilkinson Microwave Anisotropy Probe, launched in 2001, improved on COBE by looking for such anisotropy at much smaller angular scales.
NASA/WMAP SCIENCE TEAMPLANCK launched in 2009, provides a capstone to the study of the cosmic microwave background.
But unambiguous confirmation of a cosmic burst of expansion known as inflation remains elusive. ES a
#Canada puts commercialization ahead of blue-sky research Canadian finance minister Jim Flaherty yesterday released the country's 2013 budget,
there is a piecemeal approach, with the government"picking winners and providing new money to the automotive, aerospace, forestry and aquaculture sectors."
#Planck telescope peers into primordial Universe The Planck space telescope has delivered the most detailed picture yet of the cosmic microwave background, the residual glow of the Big bang. Unveiling the results from the##700-million (US$904-million) European space agency (ESA) probe,
scientists say that the images shed fresh light on the first instants of the Universe s birth and peg the age of the Universe at 13.82 billion years#slightly older than previously estimated."
"For cosmologists, this map is a gold mine of information, says George Efstathiou, director of the Kavli Institute for Cosmology at the University of Cambridge, UK,
and one of Planck s lead researchers. The results strongly support the idea that in the 10##32 seconds or so after the Big bang,
the Universe expanded at a staggering rate#a process dubbed inflation. Inflation would explain why the Universe is so big,
and why we cannot detect any curvature in the fabric of space (other than the tiny indentations caused by massive objects such as black holes).
The sudden ballooning also amplified quantum fluctuations into clumps of matter that went on to seed the first stars,
and, eventually, the straggly superclusters of galaxies that now span hundreds of millions of parsecs.
The cosmic microwave background radiation studied by Planck dates from about 380,000 years after the Big bang, by
which time the Universe had cooled to a few thousand degrees and neutral atoms of hydrogen and helium were beginning to form from the seething mass of charged plasma.
That transition allowed photons to travel unimpeded through space, in a pattern that carried the echoes of inflation.
Those photons are still out there today as a dim glow of microwaves with a temperature of just 2. 7 kelvin.
Since the cosmic microwave background was detected first in 1964, two space-based experiments#the Cosmic Background Explorer (COBE) and the Wilkinson Microwave Anisotropy Probe (WMAP)# have mapped the tiny temperature variations within it.
Those data have enabled cosmologists to work out when the Big bang happened, estimate the amount of unseen dark matter in the cosmos
and measure the dark energy that is accelerating the expansion of the Universe. Planck, launched in 2009,
is more than three times more sensitive than the WMAP. Its high-frequency microwave detector is cooled to just 0. 1 degrees above absolute zero
which enables it to detect temperature variations as small as a millionth of a degree.
These precise measurements show that the Universe is expanding slightly slower than estimated from WMAP's data.
which suggests that the Universe is about 50 million years older than calculated from WMAP images.
The Planck data also implies that dark energy makes up 68.3%of the energy density of the Universe,
The contribution of dark matter swells from 22.7%to 26.8%%leaving normal matter making up just under 5%.Planck also confirmed some oddities earlier picked up by the WMAP.
The simplest models of inflation predict that fluctuations in the cosmic microwave background should look the same all over the sky.
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