SPACE.com: A space rock explosion earlier this month over an island region of Indonesia is now being viewed as perhaps the biggest object to tangle with Earth in more than a decade.
On 8 October, reports from Indonesia told of a loud air blast around 11:00 am local time. One report indicated a bright fireball, accompanied by an explosion and lingering dust cloud, as the origin of the air blast.
According to experts at the NASA/JPL Near-Earth Object Program Office in Pasadena, California—Don Yeomans, Paul Chodas, Steve Chesley—the blast is thought to be due to the atmospheric entry of an asteroid more than 10 meters in diameter.
Due to atmospheric pressure, the object is thought to have detonated in the atmosphere, yielding an energy release of about 50 kilotons.
Usatoday.com: The most likely explanation for what force could have permanently bent a ring in our Milky Way Galaxy within the last 60 million years appears to be a giant clump of dark matter.
The dark matter is suspected to consist of enigmatic physics particles born in the fiery aftermath of the Big Bang and weighing as much as 10 million suns.
Left behind by this cataclysm was a tilted swirl of newborn stars circling within the galaxy called the "Gould Belt," which incidentally may have sent comets hurtling towards Earth, suggests astrophysicist Kenji Bekki of Australia's University of New South Wales in a recent Monthly Notices of the Royal Astronomical Society journal.
Science: Many aerosols cool the atmosphere (a negative forcing), whereas ozone and black carbon aerosol have a warming effect (a positive forcing).
There is thus a strong motivation for treating air pollution control and climate change in common policy frameworks, argue Almut Arneth and colleagues in Science.
However, changes in pollutant and precursor emissions, atmospheric burden, and radiative forcing are not necessarily proportional.
Drew T. Shindell and colleagues at NASA Goddard Institute for Space Studies in New York, report that current models do not capture many of the complex atmospheric processes involving aerosols and reactive trace gases.
As Arneth and colleagues state:
Changing aerosol burdens may alter local and regional cloud cover and precipitation, change the intensity or timing of the monsoon circulation, and even shift precipitation across national borders. Changes in cloud cover and precipitation will also feed back on the photochemistry and rainout of short-lived species. These issues must be considered if aerosol emissions are to become part of climate policy.
Given the toxicity of pollutants, the question is not whether ever stricter air pollution controls will be implemented, but when and where. The jury is out on whether air pollution control will accelerate or mitigate climate change. Still, the studies available to date mostly suggest that air pollution control will accelerate warming in the coming decades.
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The Observer: At first glance, the piece of metal in Steve Myers's hands could be taken for a harmonica or a pen. Only on closer inspection can you make out its true nature.
Myers, director of accelerators at the CERN particle physics laboratory outside Geneva, is clutching a section of copper piping from which a flat electrical cable is protruding.
It looks unremarkable. Yet a piece of cable like this one was responsible last year for the world's most expensive short circuit.
More than $50 million-worth of damage was done to the Large Hadron Collider (LHC), the most advanced particle accelerator ever built, a few days after its ceremonial opening.
It has taken Myers—and hundreds of other CERN scientists—more than a year to pinpoint the guilty piece of cable and repair the wreckage.
"It was a very small piece, but it did immense damage," he said. It remains to be seen whether Myers can fix CERN's tattered technological reputation in the process—when his team restart their great machine in a few weeks. "I am not a nervous person," said the 63-year-old Belfast-born engineer. "And that is probably just as well."
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Physics Today: A Russian Rokot launcher has successfully taken off from the Plesetsk Cosmodrome with Europe's Soil Moisture and Ocean Salinity satellite on board.
SMOS, a small 658-kg satellite, will provide the first global maps of the amount of moisture held in soils and of the quantity of salts dissolved in the oceans.
"Salinity is one of the drivers for the Thermohaline Circulation, the large network of currents that steers heat exchanges within the oceans on a global scale," says Volker Liebig, ESA's director of Earth observation programs. "Its survey has long been awaited by climatologists who try to predict the long-term effects of today's climate change."
The satellite was developed by ESA in cooperation with France's CNES and Spain's Centro para el Desarrollo Tecnológico Industrial (CDTI).
Its only instrument is called the Microwave Imaging Radiometer using Aperture Synthesis (MIRAS). The device works by connecting together 69 receivers mounted on three deployable arms to measure the temperature of the reflection of Earth's surface in the microwave frequency range. This temperature is linked to both the actual temperature of the surface and its conductive characteristics, which are in turn linked to soil moisture for land surface and to water salinity for sea surface.
"The data collected by SMOS will complement measurements already performed on the ground and at sea to monitor water exchanges on a global scale," says Liebig. "Since these exchanges—most of which occur in remote areas—directly affect the weather, they are of paramount importance to meteorologists."
SMOS is the second satellite launched under ESA's Earth Explorer program to gather new environmental data. It follows the Gravity and steady-state Ocean Circulation Explorer (GOCE), which was launched in March.
Next February, Cryosat-2 will be launched to measure the thickness of the ice sheets. This will be followed in 2011 by ADM-Aeolus—designed to study atmospheric dynamics—and the Swarm mission to monitor the weakening of Earth's magnetic field. Finally in 2013 the EarthCARE mission will study clouds and aerosols.
Continue reading ESA satellite to track water cycle.
Nature: Materials that combine ferroic properties—such as ferromagnetism and ferroelectricity—are highly desirable, but rare. A new class of multiferroic solids heralds a fresh approach for making such materials.
Multiferroics are attractive candidates for use in electrically controllable microwave elements, magnetic-field sensors and possibly even in spintronics.
Charles Stross: Homo Sapiens appear to be an infestation on this planet.
After the slow-burning evolution of hominins in Africa, our ancestral populations erupted out into Eurasia in a geological eye-blink, spread into the Americas by way of the Bering land bridge (sea levels being somewhat lower during the ice ages) and finally reaching even the remotest islands of oceania around twelve thousand years ago.Today we're ubiquitous. Even our pre-industrial ancestral cultures occupied a slew of geographical environments that put cockroaches to shame.
So you'd think that, to a first approximation, the Earth is inhabitable by human beings. And this tends to colour our approach the prospects of finding extrasolar planets that might be hospitable to human life.
"Actually," says Charles Stross, "I think this is not quite the case. In fact, to a first approximation, from the perspective of prospective interstellar colonists, the Earth is uninhabitable."
That we could imagine otherwise bespeaks a profound cognitive bias on our part (and a degree of relativism: because when all's said and done, the Earth is a lot less hostile than, say, the surface of Venus or the cloud base of Jupiter).Why is the Earth uninhabitable? To find out, read the entire column.
WSJ.com: The H1-B visa program that feeds skilled workers to top-tier US technology companies and universities is on track to leave thousands of spots unfilled for the first time since 2003, a sign of how the weak economy has eroded employment even among highly trained professionals.
Last year, even as the recession began to bite, employers snapped up the 65,000 visas available in just one day. This year, however, as of 25 September—nearly six months after the US government began accepting applications—only 46,700 petitions had been filed.
In addition to the weak economy, companies have curbed applications in the face of rising costs associated with hiring foreign-born workers.
While the number of visa holders is small compared with the US work force, their contribution is huge, employers say. For example, last year 35% of Microsoft's patent applications in the US came from new inventions by visa and green-card holders, according to company general counsel Brad Smith.
BBC news: Drawn half a millennium ago and then swiftly forgotten, one map made us see the world as we know it today... and helped name America. But, as BBC news reporter Toby Lester discovered, the first map that outlined the continents of the world as we know them today, also named America based on a pun.
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Wired.com: A cell in the eye may be worth two in the beak, at least when it comes to a migratory bird's magnetic compass.
In European robins (right image), a visual center in the brain and light-sensing cells in the eye—not magnetic sensing cells in the beak—allow the songbirds to sense which direction is north and migrate correctly, a new study finds. The study published in Nature, may improve conservation efforts for migratory birds.
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The Daily Telegraph: UK academics are calling on members of the public to use their mobile phones to record their local soundscape and send them the results.
It is hoped that the clips will then make up a detailed acoustic map of the noise environment around the country and help offset the growing menace of noise pollution.
The project—which will make the raw acoustic data available on the web—aims to get a better idea of why some sounds add to the atmosphere of a place and others detract and cause annoyance.
Nature: Forty years ago today the first message was sent between computers on the ARPANET. Vinton G. Cerf, who was a principal programmer on the project, reflects on how our online world was shaped by its innovative origins.
NPR: The NASA swift satellite has discovered the most distant γ-ray burst seen and the earliest astronomical object ever observed in cosmic history.
Two teams of scientists made the discovery, which they report in Nature.
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guardian.co.uk: The chief executive of defense research technology firm QinetiQ has quit the company just hours after it was criticized by the official report into a 2006 Nimrod plane crash in Afghanistan, which claimed 14 lives.
Graham Love, who has run the company for the last four years, is departing on 30 November. His replacement, Leo Quinn, is the former chief executive of bank-note maker DeLaRue.
"We have been looking at succession planning for over a year," a company spokesman said. "[It is] mistaken to directly link the two events."
Science: The blogosphere has been having a field day with global warming's apparent decade-long stagnation. Negotiators are working toward an international global warming agreement to be signed in Copenhagen in December, yet there hasn't been any warming for a decade. What's the point, bloggers ask?
Climate researchers are beginning to answer back in their preferred venue, the peer-reviewed literature. The pause in warming is real enough, but it's just temporary, they argue from their analyses. A natural swing in climate to the cool side has been holding greenhouse warming back, and such swings don't last forever. "In the end, global warming will prevail," says climate scientist Gavin Schmidt of NASA's Goddard Institute for Space Studies (GISS) in New York City.
latimes.com: A big earthquake and resultant fire could trigger potentially deadly releases of radioactive materials from Los Alamos National Laboratory in New Mexico due to "major deficiencies" in the nuclear weapons lab's safety planning, federal safety experts warned Tuesday.
The warning from the Defense Nuclear Facilities Safety Board was sent to Energy Secretary Steven Chu, urging him to "execute both immediate and long-term actions."
The Daily Telegraph: A team of fluid dynamics experts have worked out what causes the so-called "teapot effect" and have come up with a way to put an end to it.
They have deduced that at low pouring speeds tea starts to stick to the inside of the spout, causing the flow to momentarily stop and then start again—in other words to dribble.
By reducing the friction between the spout and the fluid, the dribble can be all but be eradicated even towards the end of a pour, claim the scientists at the University of Lyon in France.
Science: For the past 5 years, Jerry Nelson and his colleagues at University of California have been working on plans for the Thirty Meter Telescope (TMT)—whose primary mirror will be a glinting mosaic of 492 hexagonal segments.
An artist's concept showing the segmented primary mirror, which has 492 hexagonal segments arranged into an f/1 hyperboloidal mirror (credit: TMT)
Meanwhile, Roger Angel and his collaborators have set their sights on building the Giant Magellan Telescope (GMTO)—whose seven monolithic 8.4-meter mirrors, arranged like flower petals, will function as a primary mirror 24.5 meters in diameter.
Artist's concept showing the seven 8.4-meter mirrors. (credit: GMTO)
If the telescopes are built—TMT on Mauna Kea in Hawaii, GMT at Las Campanas—each will capture images up to 10 times sharper than today's best ground-based telescopes.
Both will shoot for the same scientific goals, looking at the first stars and galaxies, studying the formation of planets and stars, the growth of black holes, and probe the nature of dark matter and dark energy. And both will cost between $700 million and $1 billion.
So far, neither telescope has come close to securing the total funding it needs, and if they are built with little federal support, the National Science Foundation would be hard pressed to provide the operating and maintenance costs.
Given the funding challenges, some astronomers say the two sides should join forces to build one telescope to rival the European Southern Observatory's proposed 42-meter segmented-mirror telescope, the European Extremely Large Telescope.
Physical Review Focus: High-energy physicists have finally pinpointed their dust problem. Inside multi-million dollar storage rings, high-speed trains of electrons are often derailed by micron-sized specks of dust. Now a team has shown that dust grains arise from sparks inside a Japanese storage ring, the KEK Photon Factory Advanced Ring as they report in an upcoming paper in Physical Review Special Topics--Accelerators and Beams.
The team also caught on video, one of the tiny grains being swept along in the electron beam. The brief flashes of dust trapped in an invisible electron beam begin about halfway through the 10-second video.
Video courtesy of Y. Tanimoto, KEK.
Various: The launch of NASA's first new rocket in 25 years earlier today has given NASA a welcome boost while the agency grapples with a revised strategy for returning to the Moon and onto Mars under tighter budget conditions.
Above is the Ares I-X test rocket taking off from Launch Complex 39B at NASA's Kennedy Space Center in Florida. Liftoff occurred at 11:30 am. EDT. Credit: NASA/Jim Grossman
The Ares I-X test flight saw the first stage solid rocket boosters taking the vehicle to an altitude of 40km. The booster stage then parachuted down into the Atlantic for recovery, while the dummy second stage crashes into the ocean.
"It is a chance for the agency to remind itself what it takes to build a vehicle," said Robert Less, Ares I-X mission manager to the BBC.
The first stage is a highly modified version of a space shuttle rocket booster.
The Ares I-X mission profile, Image credit: NASA.
The recent Augustine Panel that looked at manned spaceflight even questioned whether Ares I is the right vehicle for the job. NASA says Ares I will be ready in 2015, others told the panel it will be longer.
The Ares I-X was rolled to the launch pad early last week.
Space.com's Jeremy Hsu goes behind the scenes of Ares I-X booster and visits the group that built it.
It represents the culmination of years of work by the rocket-minded ATK Space Systems in Utah and almost 1,000 other NASA workers and private contractors across 17 states.To ensure that they see the fruits of their labor, technicians have installed more than 700 sensors on the $445 million Ares I-X test vehicle.
It may be the only visible success of the program says New York Times reporter Kenneth Chang.
"Critics of the Ares I, which is part of NASA’s Constellation program intended to return astronauts to the Moon by 2020, have described it as too expensive, underpowered and technically flawed."
Continue reading Ares I test rocket takes off.
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