Science & TechnologyS


Info

Smart dust could give early warning of space storms

Jessica Griggs
New Scientist
Sun, 07 Feb 2010 12:53 UTC
Image
© SOHO/ESA/NASA/SPLSolar flare, headed our way.
A swarm of "smart dust" spacecraft, positioned at a sweet spot between the Earth and the sun, could alert us to the approach of dangerous space storms well before a conventional craft can. The first prototypes are due for launch into low-Earth orbit this year, perhaps as early as May.

Mason Peck, a mechanical engineer at Cornell University in Ithaca, New York, and his colleague Justin Atchison have designed a 1-centimetre-square spacecraft that is 25 micrometres thick and weighs under 7.5 milligrams. The craft is modelled on the dust particles that orbit the sun and are propelled by the photons streaming out from the sun. This solar radiation pressure would have a negligible effect on normal-sized spacecraft but is significant at the millimetre scale. The grooved edges of the "spacecraft-on-a chip" deflect incoming photons in such a way as to ensure it always faces the sun.

The craft's miniature size would let it hitch a ride into space on the back of another satellite mission headed for the Lagrange point between the Earth and the sun. A Lagrange point is a kind of gravitational sweet spot, where a small object can be stationary relative to two larger objects.
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Meteor

Astronomers Spot Aftermath of Asteroid Collision


Boulder Weekly / McClatchy-Tribune News Service
Fri, 05 Feb 2010 20:14 UTC
Image
© NASA, ESA, D. Jewitt (UCLA)Is this mystery object a comet or the result of an asteroid collision?
An object imaged last week by the Hubble Space Telescope looks at first glance to be a comet, but a closer examination indicates it is something researchers have never seen before - the immediate aftermath of two asteroids colliding.

The scattered debris that looks like a comet's tail is actually the result of two asteroids colliding nearly head-on at more than 11,000 miles per hour, scattering pieces in all directions, NASA announced earlier this week. The asteroid belt between Mars and Jupiter, where the collision occurred, contains the remains of many such events from the distant past, but this is first time that researchers have observed such debris so soon after a collision.

The object, called P/2010 A2, was first observed Jan. 6 by the Lincoln Near-Earth Asteroid Research program, and astronomers thought it was a comet. But images taken by Hubble on Jan. 25 and 29 show something far different.

Comets are icy bodies that fall into the inner solar system from distant reservoirs in the Kuiper Belt and Oort Cloud. As they warm up, they shed particles and water vapor that are pushed away from the comet in a smooth tail by solar pressure.

Comment: For a closer look at meteorites, asteroids and comets read Laura Knight-Jadczyk's Meteorites, Asteroids, and Comets: Damages, Disasters, Injuries, Deaths, and Very Close Calls.

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Info

Electric Planes Could Transform How We Fly

Charles Choi
TechNewsDaily.com
Sun, 07 Feb 2010 09:49 UTC
As the promise of electric cars grows, so too does the potential of electric planes. These aircraft, whose motors are far more efficient, reliable and quiet than internal combustion engines, could help transform how we fly - if a few problems could be solved.

Electric motors are three to four times better than internal combustion engines at driving an airplane propeller. And the reliability of electric motors is "perhaps 10 times or even 20 times that of a piston engine," said Brien Seeley, president of the Comparative Aircraft Flight Efficiency (CAFE) Foundation, an independent flight test agency which hosts NASA's Centennial Challenges for Aeronautics.
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Sun

High-Tech Glitter to Create Flexible Solar Panels

Adam Hadhazy
TechNewsDaily.com
Sun, 07 Feb 2010 09:43 UTC
Researchers have unveiled super-small solar cells no bigger than the pieces of glitter on your holiday ornaments and cards. These highly efficient photovoltaics could be game-changers in the burgeoning field of solar power, allowing arrays of microcells to be placed on bendable or curved surfaces and even woven into clothing.

Unlike the conventional, rigid solar cells deployed as flat panels on rooftops, for instance, the new miniscule cells could be encapsulated in flexible plastic and made to fit virtually any object.

"With this technology, one can envision ubiquitous [solar-powered] devices," said Greg Nielson, lead investigator at Sandia National Laboratories in New Mexico.
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Magnify

Archaeologists stumble on 8,000-year-old skeleton in Kenyir Lake


The Star Online
Sun, 07 Feb 2010 09:39 UTC
Hulu Terengganu - Archaeologists have stumbled upon human skeletal remains believed to be from the Mesolithic Age in the Bewah Cave in the Kenyir Lake area, according to a university professor.

The remains, believed to be those of a youth, are estimated to be between 8,000 and 11,000 years old, said Prof Datuk Dr Nik Hasan Shuhaimi Nik Abdul Rahman, deputy director of the Institute of the Malay World and Civilisation (ATMA) of Universiti Kebangsaan Malaysia (UKM).

The remains were uncovered by archaeologists from UKM, the Museums Department and the Terengganu Museum Board at a depth of 65 to 70 centimetres, he told reporters after a visit by Terengganu Menteri Besar Datuk Ahmad Said and reporters to the cave on Saturday.
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Cuneiform tablets, Seals and Tombs Unearthed in Syria

Ruaa AL-Jazaeri
Global Arab Network
Sun, 07 Feb 2010 09:34 UTC
Image
© Unknown
According to Syrian media, archaeological expeditions working at North-eastern Syria (Hasaka Province) have discovered several collective tombs and parts of seals with different shapes in addition to 27 cuneiform tablets dating back to 2500 BC.

Director of Hasska Antiquities Department Abdul-Masih Baghdo said that the British expedition working at the site of Tal Barak had studied many clay jars discovered at the site.

He added that the expedition also studied several archaeological findings to find out the location of the buildings dating back to the Babylonian and Mitanni periods.

Three collective tombs were also unearthed at the site of Tal Majnuna, dating back to the period between 3600 to 3800 BC.
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Magnify

Wall with Maya Seignior Glyphs Discovered at Archaeological Zone


artdaily.org
Sun, 07 Feb 2010 09:28 UTC
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© EFE/Héctor Montaño/INAHThe discovery adds up to the sarcophagus recently uncovered by specialists.
Chiapas, Mexico.- A wall with a rich glyphic text that includes the complete name of the ruler that founded one of the most important Maya military seigniories was discovered in Tonina Archaeological Zone, in Chiapas. Epigraphists point out that the finding will bring in new information regarding Maya grammar, since it shows linguistic features yet to be deciphered.

The discovery adds up to the sarcophagus recently uncovered by specialists of the National Institute of Anthropology and History (INAH). The wall dated in 708 AD was detected at El Palacio; a stucco portrait of K'inich B'aaknal Chaahk, the most powerful seignior of the ancient Maya city, was found as well.
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Beer

Explorer's Whiskey Found Buried Near South Pole

Lauren Frayer
AOL News
Sat, 06 Feb 2010 16:26 UTC
Image
© New Zealand Antarctic Heritage Trust
It's probably the most sought-after scotch in history - crates of whiskey buried in Antarctica by the famed explorer Ernest Shackleton a century ago. He abandoned them on a failed attempt to reach the South Pole in 1909, and they've been on ice - literally - ever since.

Researchers from New Zealand found the crates while restoring a hut Shackleton built and used during the expedition. He and his team were forced to cut short the trip and abandon supplies, including their booze, to sail away before winter ice trapped them there.

Comment:


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Sherlock

Stonehenge's secret: archaeologist uncovers evidence of encircling hedges


The Guardian
Thu, 04 Feb 2010 16:08 UTC
stonehedge
english-heritage.org.uk
Survey of landscape suggests prehistoric monument was surrounded by two circular hedges.

The Monty Python knights who craved a shrubbery were not so far off the historical mark: archaeologists have uncovered startling evidence of The Great Stonehenge Hedge.

Inevitably dubbed Stonehedge, the evidence from a new survey of the Stonehenge landscape suggests that 4,000 years ago the world's most famous prehistoric monument was surrounded by two circular hedges, planted on low concentric banks.

The best guess of the archaeologists from English Heritage, who carried out the first detailed survey of the landscape of the monument since the Ordnance Survey maps of 1919, is that the hedges could have served as screens keeping even more secret from the crowd the ceremonies carried out by the elite allowed inside the stone circle.
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Meteor

Dark Ages: Did a comet impact cause global catastrophe around 500 A.D.?

Richard A. Lovett
National Geographic News
Wed, 03 Feb 2010 11:04 UTC
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© Detlev van Ravenswaay, Astrofoto, Peter Arnold Images, PhotolibraryAn asteroid hurtles toward Earth in an artist's rendering.
Double impact may have caused tsunami, global cooling

Pieces of a giant asteroid or comet that broke apart over Earth may have crashed off Australia about 1,500 years ago, says a scientist who has found evidence of the possible impact craters.

Satellite measurements of the Gulf of Carpentaria (see map) revealed tiny changes in sea level that are signs of impact craters on the seabed below, according to new research by marine geophysicist Dallas Abbott.

Based on the satellite data, one crater should be about 11 miles (18 kilometers) wide, while the other should be 7.4 miles (12 kilometers) wide.

For years Abbott, of Columbia University's Lamont-Doherty Earth Observatory, has argued that V-shaped sand dunes along the gulf coast are evidence of a tsunami triggered by an impact.

"These dunes are like arrows that point toward their source," Abbott said. In this case, the dunes converge on a single point in the gulf - the same spot where Abbott found the two sea-surface depressions.

The new work is the latest among several clues linking a major impact event to an episode of global cooling that affected crop harvests from A.D. 536 to 545, Abbott contends.

According to the theory, material thrown high into the atmosphere by the Carpentaria strike probably triggered the cooling, which has been pinpointed in tree-ring data from Asia and Europe.

What's more, around the same time the Roman Empire was falling apart in Europe, Aborigines in Australia may have witnessed and recorded the double impact, she said.

Comment: For an in-depth study, read Laura Knight-Jadczyk's review of New Light on the Black Death: The Cosmic Connection.

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