Science & TechnologyS


Bug

Common Chemical Causes Locusts to Swarm

Randolph E. Schmid
The Associated Press
Thu, 29 Jan 2009 19:15 UTC
A chemical that affects people's moods also can transform easygoing desert locusts into terrifying swarms that ravage the countryside, scientists report.

"Here we have a solitary and lonely creature, the desert locust. But just give them a little serotonin, and they go and join a gang," observed Malcolm Burrows of the University of Cambridge in England.

The brain chemical serotonin has been linked to mood in people. It plays a role in sexual desire, appetite, sleep, memory and learning, too.

Under certain conditions, locusts triple the amount of serotonin in their systems, changing the insects from loners to pack animals, Burrows and his co-authors report in Friday's edition of the journal Science.
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Stormtrooper

Truck-mounted laser shoots down spy drone

Paul Marks
New Scientist
Thu, 29 Jan 2009 18:43 UTC
mounted laser
© BoeingUncrewed drones have become popular with armed forces around the world and they are tricky to defend against, but a truck-mounted laser that can shoot them down could dilute their usefulness.

Uncrewed aerial vehicles are "revolutionary" technology that America must invest more in. Not the military's view, but that of President Obama in a statement on his defence priorities.

But a technology designed to make UAVs history is already showing promise - aerospace firm Boeing reports that their prototype truck-mounted laser has shot down a UAV at a missile range in New Mexico.

Uncrewed aircraft are powerful tools because they remove pilots from harm's way and because they can be built smaller than conventional spy or combat planes, making them harder to knock out of the sky.

UAVs come in all shapes and sizes: from the hand-launched Aerovironment Raven surveillance plane to the small airliner-sized Global Hawk.
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Telescope

How was the solar system built?

Richard Webb
New Scientist
Thu, 29 Jan 2009 18:37 UTC
Image
© T Pyle (SSC) / JPL-Caltech / NASA)This artist's concept depicts a distant hypothetical solar system, similar to the one recently discovered with the Spitzer Space Telescope. A narrow asteroid belt, filled with rocks and dusty debris, orbits a star similar to our own Sun when it was approximately 30 million years old (about the time Earth formed). Within the belt, a hypothetical planet also circles the star.

Looking at the planets of the solar system, you could be forgiven for thinking that if they do belong to the same family, it is by adoption rather than kinship. Not so: the story of the solar system's birth reveals that they are blood siblings, all created from the same molecular cloud whose collapse formed the sun. You might also think that these disparate bodies are scattered across the solar system without rhyme or reason. But move any piece of the solar system today, or try to add anything more, and the whole construction would be thrown fatally out of kilter. So how exactly did this delicate architecture come to be?

When our sun formed, it swallowed about 99.8 per cent of the debris cloud around it. According to the generally favoured picture, the lean pickings that remained were sculpted by gravity into a thin disc of gas and dust encircling the newborn star's midriff. As the dust grains of this disc orbited the sun, they collided and progressively coagulated into ever larger bodies. In the disc's innermost region, the ignition and burning of hydrogen in the sun made things very hot, so that only metals and silicate minerals with high melting points were present in solid form. Bodies in that region could only reach a certain size - producing the four small rocky planets of the inner solar system: Mercury, Venus, Earth and Mars.
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Info

Hatred of slavery drove Darwin to emancipate all life

Rowan Hooper
New Scientist
Thu, 29 Jan 2009 18:18 UTC
Image
© Library of Congress"Am I Not a Man and a Brother?" - the image of a slave in chains was cast in pottery by Josiah Wedgwood, Darwin's grandfather, and is used here to illustrate an 1837 anti-slavery poem.

For someone who came up with what has justly been described as "the single best idea anyone has ever had", Darwin has been vilified to an extraordinary degree. Clearly, his achievement of uniting all species under a common ancestor outraged millions, and still does. The book, Darwin's Sacred Cause, spectacularly humanises him, showing how he was driven by the great moral cause of his day: opposition to slavery.

Adrian Desmond and James Moore have come up with something astonishing: a radical new explanation of the force that drove Darwin. I hesitate to call this work definitive, as that was how the same authors' epic biography of Darwin was described in 1991. I wouldn't have thought it possible to further elevate the standing Darwin and his work have, but by trawling through reams of correspondence and notebooks, Desmond and Moore have done just that.

Darwin's family was passionately abolitionist and he continually mixed with people devoted to the cause. On his travels aboard the Beagle he was outraged by the suffering he saw inflicted by slavery, and that left a bigger impression on him than, say, the Galapagos finches.
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Meteor

Mammoth-Killing Comet Questioned

Jason Palmer
BBC News
Thu, 29 Jan 2009 13:49 UTC
mammoths
© BBC NewsWoolly mammoths were not the only ones to die out 13,000 years ago.
A study of wildfires after the last ice age has cast doubt on the theory that a giant comet impact wiped out woolly mammoths and prehistoric humans.

Analysis of charcoal and pollen records from around 13,000 years ago showed no evidence of continental-scale fires the cometary impact theory suggests.

However, the results showed increased fires after periods of climate change.
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Einstein

Best of the Web: Belief in God 'childish,' Jews not chosen people: Einstein letter


Agence France-Presse
Tue, 13 May 2008 10:09 UTC

Comment: References to the letter Einstein wrote in regards to religion and the Jewish people, though published in the mainstream media during May of last year, appear more pertinent now than ever before, in view of Israel's crimes committed in Gaza.


Albert Einstein
© Albert Einstein
Albert Einstein described belief in God as "childish superstition" and said Jews were not the chosen people, in a letter to be sold in London this week, an auctioneer said Tuesday.

The father of relativity, whose previously known views on religion have been more ambivalent and fuelled much discussion, made the comments in response to a philosopher in 1954.

As a Jew himself, Einstein said he had a great affinity with Jewish people but said they "have no different quality for me than all other people".
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Info

Six Biggest Mysteries of our Solar System


New Scientist
Wed, 28 Jan 2009 18:29 UTC
Image
© Unknown

Once upon a time, 4.6 billion years ago, something was brewing in an unremarkable backwater of the Milky Way. The ragbag of stuff that suffuses the inconsequential, in-between bits of all galaxies - hydrogen and helium gas with just a sprinkling of solid dust - had begun to condense and form molecules. Unable to resist its own weight, part of this newly formed molecular cloud collapsed in on itself. In the ensuing heat and confusion, a star was born - our sun.

We don't know exactly what kick-started this process. Perhaps, with pleasing symmetry, it was the shock wave from the explosive death throes of a nearby star. It was not, at any rate, a particularly unusual event. It had happened countless times since the Milky Way itself came into existence about 13 billion years ago, and in our telescopes we can see it still going on in distant parts of our galaxy today. As stars go, the sun is nothing out of the ordinary.
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Saturn

Astronomers Get a Sizzling Weather Report from a Distant Planet


PhysOrg
Wed, 28 Jan 2009 18:25 UTC
Planet
© D. Kasen, J. Langton, and G. Laughlin (UCSC)The planet HD80606b glows orange from its own heat in this computer-generated image. A massive storm has formed in response to the pulse of heat delivered during the planet's close swing past its star. The blue crescent is reflected light from the star.
Astronomers have observed the intense heating of a distant planet as it swung close to its parent star, providing important clues to the atmospheric properties of the planet. The observations enabled astronomers at the University of California, Santa Cruz, to generate realistic images of the planet by feeding the data into computer simulations of the planet's atmosphere.

"We can't get a direct image of the planet, but we can deduce what it would look like if you were there. The ability to go beyond an artist's interpretation and do realistic simulations of what you would actually see is very exciting," said Gregory Laughlin, professor of astronomy and astrophysics at UCSC. Laughlin is lead author of a new report on the findings published this week in Nature.

The researchers used NASA's Spitzer Space Telescope to obtain infrared measurements of the heat emanating from the planet as it whipped behind and close to its star. In just six hours, the planet's temperature rose from 800 to 1,500 Kelvin (980 to 2,240 degrees Fahrenheit).
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Info

Mars polar water is pure


Agence France-Presse
Wed, 28 Jan 2009 18:24 UTC
Image
© Agence France-PresseMars Northern Polar Ice Cap

A large ice cap found at Mars' northern pole is "of a very high degree of purity," according to an international study reported on Tuesday by French researchers.

Radar data sent back by the US Mars Reconnaissance Orbiter (MRO) point to 95 percent purity in this deposit, France's National Institute of Sciences of the Universe (Insu) said in a press release.

The Martian polar regions are believed to hold the equivalent of two to three million cubic kilometres" (0.47-0.72 million cu. miles) of ice, it said.
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Telescope

Most Large Galaxies Formed Without Mergers


AScribe Newswire
Wed, 28 Jan 2009 14:36 UTC
Three leading-edge researchers in the field of galaxy formation have published their findings that most large galaxies have formed and developed without the involvement of galaxy mergers. This historic development in cosmology provides an important missing piece to the universe's cosmological puzzle.

Avishai Dekel published his scientific paper this month, Michael J. Disney published his late last year and Jerome Drexler authored relevant books in 2006 and 2008.The most obvious immediate effect could be a paradigm shift away from the 24-year-old Cold Dark Matter theory of weakly interacting massive particles (WIMPs).

The UC Santa Cruz (UCSC) central doctrine for Cold Dark Matter has been that small galaxies form first and larger galaxies are formed through mergers of smaller galaxies.
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