Science & TechnologyS


Meteor

Kansas scientists probe mysterious possible comet strikes on Earth

Brendan M. Lynch
University of Kansas
Mon, 14 Dec 2009 20:25 UTC
An investigation by the University of Kansas' Adrian Melott and colleagues reveals a promising new method of detecting past comet strikes upon Earth and gauging their frequency

It's the stuff of a Hollywood disaster epic: A comet plunges from outer space into the Earth's atmosphere, splitting the sky with a devastating shock wave that flattens forests and shakes the countryside.

But this isn't a disaster movie plotline.

"Comet impacts might be much more frequent than we expect," said Adrian Melott, professor of physics and astronomy at the University of Kansas. "There's a lot of interest in the rate of impact events upon the Earth. We really don't know the rate very well because most craters end up being destroyed by erosion or the comets go into the ocean and we don't know that they're there. We really don't have a good handle on the rate of impacts on the Earth."
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Sun

Theorists propose a new way to shine -- and a new kind of star

Kevin Mayhood
Case Western Reserve University
Mon, 14 Dec 2009 20:22 UTC
Dying, for stars, has just gotten more complicated.

For some stellar objects, the final phase before or instead of collapsing into a black hole may be what a group of physicists is calling an electroweak star.

Glenn Starkman, a professor of physics at Case Western Reserve University, together with former graduate students and post-docs De-Chang Dai and Dejan Stojkovic, now at the State University of New York in Buffalo, and Arthur Lue, at MIT's Lincoln Lab, offer a description of the structure of an electroweak star in a paper submitted to Physical Review Letters and posted online at http://arxiv.org/abs/0912.0520.
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Sun

New planet discoveries suggest low-mass planets are common around nearby star

Tim Stephens
University of California - Santa Cruz
Mon, 14 Dec 2009 20:17 UTC
An international team of planet hunters has discovered as many as six low-mass planets around two nearby Sun-like stars, including two "super-Earths" with masses 5 and 7.5 times the mass of Earth. The researchers, led by Steven Vogt of the University of California, Santa Cruz, and Paul Butler of the Carnegie Institution of Washington, said the two "super-Earths" are the first ones found around Sun-like stars.

"These detections indicate that low-mass planets are quite common around nearby stars. The discovery of potentially habitable nearby worlds may be just a few years away," said Vogt, a professor of astronomy and astrophysics at UCSC.

The team found the new planet systems by combining data gathered at the W. M. Keck Observatory in Hawaii and the Anglo-Australian Telescope (AAT) in New South Wales, Australia. Two papers describing the new planets have been accepted for publication in the Astrophysical Journal.
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Meteor

Infrared space telescope launched from California

Steve Gorman, Dan Whitcomb and Cynthia Osterman
Reuters
Mon, 14 Dec 2009 16:26 UTC
NASA's new infrared space telescope was launched into orbit on Monday on a 10-month mission expected to reveal previously unseen objects ranging from near-Earth asteroids to some of the most distant galaxies in the cosmos.

The Wide-field Infrared Survey Explorer, or WISE, was carried into a polar orbit 326 miles above Earth by a Delta II rocket that lifted off before dawn from Vandenberg Air Force Base in central California.

"All systems are looking good, and we are on our way to seeing the entire sky better than ever before," said William Irace, the mission's project manager at NASA's Jet Propulsion Laboratory in Pasadena.
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Magnify

ClimateGate: A closer look at some of the 'tricks' by the email authors

David Rose
Mail Online
Sun, 13 Dec 2009 01:49 UTC
The claim was both simple and terrifying: that temperatures on planet Earth are now 'likely the highest in at least the past 1,300 years'. As its authors from the United Nations Intergovernmental Panel on Climate Change (IPCC) must have expected, it made headlines around the world.

Yet some of the scientists who helped to draft it, The Mail on Sunday can reveal, harboured uncomfortable doubts. In the words of one, David Rind from the US space agency Nasa, it 'looks like there were years around 1000AD that could have been just as warm'.
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Magnify

Mystery Volcano May Have Triggered Mini Ice Age


National Public Radio
Sat, 12 Dec 2009 09:20 UTC
Scientists say evidence in the ice of Antarctica and Greenland shows a volcanic eruption, probably near the equator, contributed to global cooling early in the 19th century.

Global warming may be making some people nervous now, but from 1810 to 1819, people worried because the Earth was colder than usual.

For an entire decade, the Earth cooled almost a full degree Fahrenheit. In fact, 1816 was known as the year without a summer. And until recently, scientists weren't quite sure why everyone was shivering.

The chill of 1816 has long been blamed on an Indonesian volcano called Tambora, which erupted the year before. But no one could figure out why the years before Tambora's eruption were also colder than usual.
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Meteor

Geminid meteors will create a sky show Sunday night


Space Weather
Sat, 12 Dec 2009 22:41 UTC
Image
© Bill Cooke
This weekend, Earth is passing through a stream of debris from extinct comet 3200 Phaethon, source of the annual Geminid meteor shower. Forecasters expect more than 100 meteors per hour to fly out of the constellation Gemini when the shower peaks on Dec. 13th and 14th. For most observers, the best time to look will be from 10 pm local time on Sunday night to dawn on Monday morning.

Click here to watch an early-arriving Geminid streak past the Moon on Dec. 9th.
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Hourglass

Genetic Ancestry Highly Correlated With Ethnic and Linguistic Groups in Asia


ScienceDaily
Thu, 10 Dec 2009 05:35 UTC
Several genome-wide studies of human genetic diversity have been conducted on European populations. Now, for the first time, these studies have been extended to 73 Southeast Asian (SEA) and East Asian (EA) populations.

In a paper titled, "Mapping Human Genetic Diversity in Asia," published in online Science on 10 Dec. 2009, over 90 scientists from the Human Genome Organisation's (HUGO's) Pan-Asian SNP Consortium report that their study conducted within and between the different populations in the Asia continent showed that genetic ancestry was highly correlated with ethnic and linguistic groups.
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Magnify

Study Provides Genetic Map of Asian Population


Press TV
Sat, 12 Dec 2009 12:50 UTC
Image
© Unknown
Scientific studies have revealed that the diverse Asian population has been formed as a result of a single migration from the south.

The Pan-Asian SNP Consortium of The Human Genome Organization (HUGO) conducted the study on almost 2,000 Asians finding genetic similarities between Asians throughout the continent.

Some 90 scientists from China, India, Indonesia, Japan, Korea, Malaysia, Philippines, Singapore, Taiwan, Thailand and the US were involved in the consortium, BBC reported.

According to the study published in the journal Science, an increasing genetic diversity from northern towards southern latitudes were found.
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Magnify

Ancient Mayans Were Nature Lovers, Not Destroyers


AndhaNews
Sat, 12 Dec 2009 06:00 UTC
In a new research, a team of archaeologists has disputed claims made by experts that the ancient Mayans agricultural practices led to their eventual collapse, and that the forest gardens cultivated by the Maya demonstrate their great appreciation for the environment.

Many archaeologists, anthropologists, and other scholars are of the opinion that the Mayan civilization's slash-and-burn approach to farming caused such widespread environmental devastation that the land simply could not sustain them.

But, research conducted by Anabel Ford, an archaeologist at UC Santa Barbara and director of the university's MesoAmerican Research Center, suggests the contrary may be true -- that the forest gardens cultivated by the Maya demonstrate their great appreciation for the environment.

A forest garden is an unplowed, tree-dominated plot that sustains biodiversity and animal habitat while producing plants for food, shelter, and medicine.
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