Science & TechnologyS


Bulb

Scientists find key to creating clean fuel from coal and waste

Alok Jha
The Observer
Sun, 15 Nov 2009 22:53 UTC
'Gasification' process enhanced to save millions of tonnes of carbon and provide energy

Millions of tonnes of carbon dioxide could be prevented from entering the atmosphere following the discovery of a way to turn coal, grass or municipal waste more efficiently into clean fuels.

Scientists have adapted a process called "gasification" which is already used to clean up dirty materials before they are used to generate electricity or to make renewable fuels. The technique involves heating organic matter to produce a mixture of hydrogen and carbon monoxide, called syngas.

However gasification is very energy-intensive, requiring high-temperature air, steam or oxygen to react with the organic material. Heating this up leads to the release of large amounts of carbon dioxide. In addition, gasification is often inefficient, leaving behind significant amounts of solid waste at the end of the process.

To find out how to make the process more efficient, researchers led by Marco Castaldi, at the department of earth and environmental engineering at Columbia University, tried varying the atmosphere in the gasifier. They found that, by adding CO2 into the steam atmosphere of a gasifier, significantly more of the biomass or coal was turned into useful syngas.
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Sun

Solar Prominence


Space Weather
Sun, 15 Nov 2009 16:26 UTC
Yesterday, Alan Friedman of Buffalo, New York, trained his telescope on the sun and waited for sunspot 1029 to reappear. But that wasn't going to happen. It was shaping up to be a dull observing session when something completely different popped into view.

Image
© Alan FriedmanCorpse of Sunspot 1029
"This magnificent looping prominence stole the show from the corpse of sunspot 1029," says Friedman. "It was the most dramatic prominence I have seen in many months."

The same prominence was putting on a show this morning, Nov. 15th, when the sun rose over the Philippines. "I was elated when I was able to see it clearly visible in the field of my eyepiece!" reports James Kevin Ty from Manila. "I quickly set up my PST (Personal Solar Telescope) and was able to monitor the prominence for more than 2 hours."
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Igloo

Best of the Web: Study of lake in Ireland shows last ice age took just months to set in

Colin Coyle
The Sunday Times
Sun, 15 Nov 2009 12:58 UTC
Burren
© UnknownBlackhead Lighthouse, where the Burren meets Galway Bay, Co. Clare, Ireland
It wasn't quite The Day After Tomorrow but it's closer than we thought. An analysis of mud from Lough Monreagh, a lake in Co Clare, has revealed that Europe was struck by a sudden mini ice age 12,800 years ago, suggesting the kind of rapid climate change previously seen only in Hollywood disaster movies.

It was believed that the "Big Freeze" took about a decade to set in. Based on an analysis of Greenland's ice cores, scientists have estimated that the Younger Dryas, as the event is also named, occurred gradually.

However, after analysing mud deposits from Lough Monreagh, William Patterson of the University of Saskatchewan in Canada, has found that the freeze took only months to take hold.

Using a very precise robotic scalpel, Patterson and his colleagues shaved 0.5mm layers from the lake bed, each representing up to three months of sediment. Carbon isotopes in the samples recorded changes to biological activity in the lake, while oxygen isotopes revealed temperature and rainfall patterns.

The tiny mud deposits showed for the first time that temperatures in Ireland dropped suddenly in the space of several months at the time of the Big Freeze.

Comment: We can add this to the growing body of data pointing to the very real prospect of a sudden onset ice age:

Fire and Ice: The Day After Tomorow

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Question

A Physics Paradox: Holes That Block Light

Karen Fox
ScienceNOW
Fri, 13 Nov 2009 07:55 UTC
holes
© J. Braun et alNo entry. A scanning electron microscope image of the gold film, which didn't let much light through its holes
The way light moves, with its fixed speed and its ability to act like either a wave or a particle, often leads to some of the most curious paradoxes of physics. A new one has just been found: Make holes in a film of gold so thin that it's already semitransparent, and less light gets through.

Because of its wave nature, light generally can't squeeze through a hole whose width is smaller than the wavelength of the light. In 1998, however, researchers discovered that light could zip through certain patterns of such holes punched into thin metal plates. Physicists figured out that the light created waves in the metal's electrons--called plasmons--that move across the material's surface in much the same way that ripples move through water. The plasmons, which have wavelengths much shorter than light, couple with each other across the tiny holes and pull the light along for the ride. One possible application is to use plasmons to build better light-based integrated circuits that would be as fast as fiber optics but less bulky.

Toward this end, researchers from the University of Stuttgart in Germany laid very thin films of gold onto pieces of glass and then used ion beams to etch the film with holes arranged in a regular, square array. These holes were smaller than the wavelength of light and, despite being so tiny, are just the kind of openings that have been shown to let light through the thicker, opaque film used in the 1998 experiment. But in the new experiment, the gold film was so thin--only 20 nanometers--that light could already shine through it. And surprisingly, less light went through the holey gold than through the original semitransparent film.
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Telescope

University of Alberta Physicist Solves Mystery of Supernova 11,000 Years Ago

Bill Graveland
The Canadian Press
Wed, 04 Nov 2009 07:14 UTC
It took a decade, but two scientists have solved the mystery behind a chunk of radioactive rock the size of a small city that has been floating in space.

It turns out the material, discovered by astronomers in 1999, is the core of a supernova, or exploding star, that occurred 11,000 years ago, but only became visible 330 years ago.

Craig Heinke, a physics professor at the University of Alberta, along with Wynn Ho of Southampton University in the United Kingdom, finally figured it out.

"I'm pretty pumped. It's been absolutely great," said Heinke in an interview with The Canadian Press. The duo's findings are being published in the Nov. 5 edition of Nature.

"This one has been a real puzzle for about 10 years since other astronomers detected this object first. We have been able to figure out what it is. We are able to show conclusively that this is a neutron star, something that was not entirely clear before," Heinke explained.
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Question

Flashback The Puzzle of the Half-Comet, Half-Asteroid


Technology Review
Wed, 05 Aug 2009 16:39 UTC
A mysterious object that ejects dust like a comet but orbits like an asteroid could be a new class of object in the solar system.

comsteroid
In 1996, astronomers identified an extraordinary object orbiting the Sun between Mars and Jupiter in a region best known for its asteroids. And yet this body, called 133P, defied description: it had the orbit of an asteroid yet emitted dust like a comet.
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Sherlock

Incas Practiced Ritual Decapitation of Enemies, Archaeologists Say


Inside Costa Rica/EFE
Sat, 14 Nov 2009 03:00 UTC
Peruvian archaeologists have reached the conclusion that the Incas decapitated their enemies to use their heads as offerings after finding three skulls in a ceremonial vessel in the southeastern city of Cuzco.

The director of Sacsayhuaman Archaeological Park, Washington Camacho, told EFE Friday that the heads found this week on Qowicarana ridge, an ancient ceremonial center north of Cuzco, could have been those of ancient chiefs or leaders of peoples who were enemies of the Incas.

For the archaeologist, the "trophy heads" could have been cut off "during a battle or in some other place after the capture of these "curacas" (chiefs of enemy peoples).

It is believed, Camacho said, that the offering of heads belonged to "the last phase of the Inca Empire," in other words around 1500, probably "when Huayna Capac reigned."
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Sherlock

Japanese Subs Found Off Hawaii Could Have Changed World War II

Peter N. Spotts
The Christian Science Monitor
Thu, 12 Nov 2009 05:00 UTC
The two Japanese submarines - which were commandeered and scuttled by the US after World War II - were much larger, faster, and stealthier than US subs of the day. One included a float-plane that could attack New York.

Marine researchers have found a pair of Imperial Japanese Navy submarines on the sea floor off Hawaii's Oahu Island - vessels so advanced for their day they would provide plenty of fodder for a fresh novel by Tom Clancy.

Known by their vessel numbers, the I-14 was a 375-foot submarine aircraft carrier - its crew capable of assembling and launching two float-plane bombers in roughly 20 minutes. The other craft, the I-201, was an attack submarine, twice as fast as any in the US fleet and faster than subs in any other Navy during World War II.

"This is one of the most significant marine-heritage findings in recent years," according to Hans Van Tilburg, a marine archaeologist who is the maritime-heritage coordinator for the National Oceanic and Atmospheric Administration's National Marine Sanctuaries in the Pacific. The find was announced Thursday.
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Sun

Lightning Strike in Africa Helps Take Pulse of Sun


ScienceDaily
Sat, 14 Nov 2009 04:00 UTC
Sunspots
© NASASunspots, which rotate around the sun's surface, tell us a great deal about our own planet.
Sunspots, which rotate around the sun's surface, tell us a great deal about our own planet. Scientists rely on them, for instance, to measure the sun's rotation or to prepare long-range forecasts of Earth's health.

But there are some years, like this one, where it's not possible to see sunspots clearly. When we're at this "solar minimum," very few, if any, sunspots are visible from Earth. That poses a problem for scientists in a new scientific field called "Space Weather," which studies the interaction between the sun and Earth's environment.

Thanks to a serendipitous discovery by Tel Aviv University's Prof. Colin Price, head of TAU's Department of Geophysics and Planetary Science, and his graduate student Yuval Reuveni, science now has a more definitive and reliable tool for measuring the sun's rotation when sunspots aren't visible -- and even when they are. The research, published in the Journal of Geophysical Research -- Space Physics, could have important implications for understanding the interactions between the sun and Earth. Best of all, it's based on observations of common, garden-variety lightning strikes here on Earth.
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Cloud Lightning

Splash! NASA Moon Crash Struck Lots of Water

Alicia Chang
The Associated Press
Sat, 14 Nov 2009 08:28 UTC
Image
© AP Photo/NASAThe ejecta plume created by the LCROSS Centaur upper stage rocket about 20 seconds after after impact
The lunar dud for space enthusiasts has become a watershed event for NASA.

Spacecraft that crashed into the moon last month kicked up a relatively small plume. But scientists have confirmed the debris contained water - 25 gallons of it - making lunar exploration exciting again.

Experts have long suspected there was water on the moon. So the thrilling discovery announced Friday sent a ripple of hope for a future astronaut outpost in a place that has always seemed barren and inhospitable.
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