Science & TechnologyS


Telescope

Strange Clouds Spotted at the Edge of Space

Jeremy Hsu
Space.com
Tue, 02 Sep 2008 16:53 UTC
A weirdly wonderful sight appeared to astronauts aboard the International Space Station this summer - thin blue clouds hovering at the boundary between Earth's atmosphere and the void.

Polar Mesospheric Clouds
©NASA
Polar Mesospheric Clouds (also known as noctilucent clouds) are transient, upper atmospheric phenomena observed usually in the summer months at high latitudes (greater than 50 degrees) of both the Northern and Southern Hemispheres. This image was acquired at an altitude of just over 200 miles in the pre-dawn hours of July 22, 2008 as the International Space Station was passing over western Mongolia in central Asia.

The noctilucent or "night-shining" clouds are at an altitude of 47 to 53 miles (76 to 85 km), where meteors and bright aurora lights are not uncommon and the atmosphere gives way to the blackness of space. The clouds remain a scientifically baffling phenomenon more than 120 years after their discovery.

"It's lovely," said Gary Thomas, an atmospheric scientist at the University of Colorado after looking at a photo taken from the space station. "And it shows just how high these clouds really are - at the very edge of space."

The clouds form at dizzying heights where the air is one hundred million times drier than the Sahara. By contrast, the common high-altitude cirrus clouds only reach heights of 11 miles (18 km) up.
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Heart

Monogamy gene found in people

Priya Shetty
ABC News
Tue, 02 Sep 2008 12:53 UTC
What if you could tell whether a man is husband material just by peering at his genes?

There has been speculation about the role of the hormone vasopressin in humans ever since we discovered that variations in where receptors for the hormone are expressed makes prairie voles strictly monogamous but meadow voles promiscuous; vasopressin is related to the "cuddle chemical" oxytocin. Now it seems variations in a section of the gene coding for a vasopressin receptor in people help to determine whether men are serial commitment-phobes or devoted husbands.
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Telescope

Venus: Global Structure Of Winds And Clouds Have Been Mapped


Science Daily
Tue, 02 Sep 2008 12:52 UTC
Venus is a planet similar in size to the Earth. Nevertheless, it is quite different in other aspects. On the one hand, it spins very slowly on its axis, taking 224 terrestrial days and, moreover, it does so in the opposite direction to that of our planet, i.e. from East to West.

Venus winds
©Basque Research
Scientists have determined in detail the global structure of the winds on Venus at the level of the clouds while, at the same time, observing unexpected changes in the wind speeds.

Its dense atmosphere of carbon dioxide with surface pressures 90 times that of Earth (equivalent to what we find at 1000 metres below the surface of our oceans), causes a runaway greenhouse effect that raises the surface temperatures up to 450ºC, to such as extent that metals like lead are in a liquid state on Venus. At a height of between 45 km and 70 km above the surface there are dense layers of sulphuric acid clouds totally covering the planet.

It was in the 1960s that they discovered, by means of telescopic observations, that the top level of cloud layers moved very rapidly, orbiting the planet in only four days, compared to the planet's own orbit of 224 days. This phenomenon was baptised the "superotation" of Venus: the winds carrying these clouds travel at 360 km/h.
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Telescope

Thousand-ruby Galaxy: Pinwheel Shines In The Darkness


Science Daily
Tue, 02 Sep 2008 12:32 UTC
ESO's Wide Field Imager has captured the intricate swirls of the spiral galaxy Messier 83, a smaller look-alike of our own Milky Way. Shining with the light of billions of stars and the ruby red glow of hydrogen gas, it is a beautiful example of a barred spiral galaxy, whose shape has led to it being nicknamed the Southern Pinwheel.

spiral galaxy Messier 83
©ESO
Colour-composite image of the startling spiral galaxy Messier 83, made using data from the Wide Field Imager on the ESO/MPG 2.2-m telescope at La Silla.

This dramatic image of the galaxy Messier 83 was captured by the Wide Field Imager at ESO's La Silla Observatory, located high in the dry desert mountains of the Chilean Atacama Desert. Messier 83 lies roughly 15 million light-years away towards the huge southern constellation of Hydra (the sea serpent). It stretches over 40 000 light-years, making it roughly 2.5 times smaller than our own Milky Way.

However, in some respects, Messier 83 is quite similar to our own galaxy. Both the Milky Way and Messier 83 possess a bar across their galactic nucleus, the dense spherical conglomeration of stars seen at the centre of the galaxies.
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Info

Origin Of Cosmic Dust That Lands On Earth Discovered


Science Daily
Tue, 02 Sep 2008 12:17 UTC
The origin of the microscopic meteorites that make up cosmic dust has been revealed for the first time in new research out September 1, 2008.

chondrite interplanetary dust particle
©E.K. Jessberger, Institut für Planetologie, Münster, Germany, and Don Brownlee, University of Washington, Seattle (via Wikipedia)
Porous chondrite interplanetary dust particle.

The research shows that some of the cosmic dust falling to Earth comes from an ancient asteroid belt between Jupiter and Mars. This research improves our knowledge of the solar system, and could provide a new and inexpensive method for understanding space.

Cosmic dust particles, originally from asteroids and comets, are minute pieces of pulverised rock. They measure up to a tenth of a millimetre in size and shroud the solar system in a thin cloud. Studying them is important because their mineral content records the conditions under which asteroids and comets were formed over four and a half billion years ago and provides an insight into the earliest history of our solar system.

The study's author, Dr Mathew Genge, from Imperial College London's Department of Earth Science and Engineering, has trekked across the globe collecting cosmic dust. He says: "There are hundreds of billions of extraterrestrial dust particles falling though our skies. This abundant resource is important since these tiny pieces of rock allow us to study distant objects in our solar system without the multi-billion dollar price tag of expensive missions."
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Info

Prehistoric Funerary Precinct Excavated In Northern Israel Dating Back To 6,750-8,500 BCE


Science Daily
Tue, 02 Sep 2008 12:13 UTC
Hebrew University excavations in the north of Israel have revealed a prehistoric funerary precinct dating back to 6,750-8,500 BCE.

Image
©Professor Nigel Goring-Morris
(1) Phallic figurine, (2) Small symbolic axe made with serpentine, (3) Shell pendants, (4) Engraved token

The precinct, a massive walled enclosure measuring 10 meters by at least 20 meters, was discovered at excavations being undertaken at Kfar HaHoresh. The Pre-Pottery Neolithic B site in the Nazareth hills of the lower Galilee is interpreted as having been a regional funerary and cult center for nearby lowland villages.

Prof. Nigel Goring-Morris of the Hebrew University's Institute of Archaeology, who is leading the excavations, says that the precinct is just one of the many finds discovered at the site this year - including remains of a fully-articulated, but tightly contracted 40 year old adult male.

Accompanying grave goods include a sickle blade and a sea shell, while a concentration of some 60 other shells were found nearby. The sea shells provide evidence for extensive exchange networks from the Mediterranean and Red Seas. Symbolic items include small plain or incised tokens. An entire herd of cattle was also found buried nearby.

While fertility symbols during this period are often associated with female imagery, at Kfar HaHoresh only phallic figurines have been found to date, including one placed as a foundation deposit in the wall of the precinct.
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Butterfly

Why Butterflies Have 'Eye Spots'

Stéphan Reebs
Live Science/Natural History Magazine
Sun, 31 Aug 2008 09:13 UTC


owl butterfly
©Iowa State University Extension
Owl butterflies in the genus Caligo are so named because of the large eyespots, or ocelli, on the undersides of the hind wings. When the butterfly lands and folds its wings over its back these eyespots are prominent and threaten would-be predators.

Some moths and butterflies bear circular, high-contrast marks on their wings that have long been thought to scare off predators by mimicking the eyes of the predators' own enemies.

Not so, say Martin Stevens and two colleagues at the University of Cambridge in England, who argue the marks work simply because they are conspicuous. (Predators are wary of prey with striking patterns, as those patterns often warn of toxic substances.)
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Network

Internet traffic begins to bypass the U.S.

John Markoff
The New York Times
Sun, 31 Aug 2008 02:59 UTC
The era of the American Internet is ending.

Invented by American computer scientists during the 1970s, the Internet has been embraced around the globe. During the network's first three decades, most Internet traffic flowed through the United States. In many cases, data sent between two locations within a given country also passed through the United States.

Engineers who help run the Internet said that it would have been impossible for the United States to maintain its hegemony over the long run because of the very nature of the Internet; it has no central point of control.

And now, the balance of power is shifting. Data is increasingly flowing around the United States, which may have intelligence--and conceivably military--consequences.
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People

Human genes can map persons' ancestry to home countries

Mohit Joshi
TopNews Health
Mon, 01 Sep 2008 21:42 UTC
London - Human genomes can actually provide a geographical map through which one can map a person's ancestry down to his/her home country, according to new research.
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Key

In Our Genes, Old Fossils Take On New Roles

David Brown
Washington Post
Mon, 01 Sep 2008 21:37 UTC
"The past is never dead. It's not even past."

-- William Faulkner

Over the past 15 years, scientists have been comparing the inherited genetic material -- the genomes -- of dozens of organisms, acquiring a life history of life itself. What they're finding would impress even novelist William Faulkner, the great chronicler of how the past never really goes away.
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