Science & TechnologyS


Telescope

Pulsating Stars Enable New Precise Determination Of Rotation Of The Milky Way


Science Daily
Sun, 21 Sep 2008 14:25 UTC
New, very precise measurements have shown that the rotation of the Milky Way is simpler than previously thought. A remarkable result from the most successful ESO instrument HARPS, shows that a much debated, apparent 'fall' of neighbourhood Cepheid stars towards our Sun stems from an intrinsic property of the Cepheids themselves.

Image
©ESO
Artist's impression of the local neighbourhood of the Sun and its setting within our galaxy, the Milky Way (see insert above). The figure shows the positions of some bright stars (in white) in the sky as well as the eight Cepheids used in the investigation (in blue). After the rotation of the Milky Way had been accounted for (red arrow), it seemed that the Cepheids were all 'falling' towards the Sun (blue arrows; these are not to scale: in reality the blue velocities are typically a factor one hundred smaller than the velocity around the Milky Way). New, very precise measurements with the HARPS instrument have shown that this apparent 'fall' is due to effects within the Cepheids themselves and is not related to the way the Milky Way rotates. The motion indicated by the blue arrows is thus an illusion. The scale of the image is given in light-years (ly).
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Star

Astrophysicists 'Weigh' Galaxy's Most Massive Star


Science Daily
Sun, 21 Sep 2008 14:21 UTC
Theoretical models of stellar formation propose the existence of very massive stars that can attain up to 150 times the mass of our Sun.

Image
©CRAQ
Astrophysicists successfully "weighed" a star of a binary system with a mass 116 times greater than that of the Sun. Located in the massive star cluster NGC 3603, the supermassive star system, known under the name of A1, has a rotation period of 3.77 days.

Until very recently, however, no scientist had discovered a star of more than 83 solar masses. Now an international team of astrophysicists, led by Université de Montréal researchers from the Centre de recherche en astrophysique du Québec (CRAQ), has found and "weighed" the most massive star to date.

Olivier Schnurr, Jules Casoli and André-Nicolas Chené, all graduates of the Université de Montréal, and professors Anthony F. J. Moffat and Nicole St-Louis, successfully "weighed" a star of a binary system with a mass 116 times greater than that of the Sun, waltzing with a companion of 89 solar masses, doubly beating the previous record and breaking the symbolic barrier of 100 solar masses for the first time.
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Robot

MIT adds robotics, voice control to wheelchair


The New England Journal of Technology
Sun, 21 Sep 2008 02:09 UTC
MIT reports its researchers are developing a robotic, voice-driven wheelchair, which would allow a user to be able to tell the wheelchair to go to a specific location, rather than control every twist and turn.
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Monkey Wrench

What happened to the Big Bang machine?

Paul Rincon
BBS News
Sun, 21 Sep 2008 01:56 UTC
The fault that has shut down the Large Hadron Collider (LHC) will be hugely disappointing for scientists and engineers following the successful "start-up" of the experiment.
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Arrow Down

Spacecraft on collision course with Earth

Mark Furman
KVAL
Sat, 20 Sep 2008 17:55 UTC


jules verne spacecruft
©ESA

Better to burn out than fade away? For a celestial chunk of important space junk, the next few weeks will offer several faint glimpses of what will soon be a fireball.

An unmanned spacecraft that ferried cargo to the International Space Station will make a few more visible passes overhead before crash landing into the Earth's atmosphere on or around Sept. 29.

The Jules Verne Automated Transfer Vehicle launched March 9, 2008, and arrived at the International Space Station on April 3, where it remained docked while tons of cargo were off-loaded -- and tons of waste materials from the space station were loaded back onto the ATV.
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Snowman

Permafrost that lives up to its name: Ancient Canadian ice survived previous warm periods

Hannah Hoag
Nature
Thu, 18 Sep 2008 15:08 UTC


Image
©Duane Froese, University of Alberta
Undergound ice can last a long time

A 740,000-year-old wedge of ice discovered in central Yukon Territory, Canada, is the oldest known ice in North America. It suggests that permafrost has survived climates warmer than today's, according to a new study.

"Previously, it was thought that the permafrost had completely disappeared from the interior about 120,000 years ago," says Duane Froese, an earth scientist at the University of Alberta in Edmonton, Canada, who is the author of the study published today in Science. "This deep permafrost appears to have been stable for more than 700,000 years, including several periods that were warmer and wetter."
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Telescope

Dark matter 'bridge to nowhere' found in cosmic void

Rachel Courtland
New Scientist
Mon, 15 Sep 2008 13:54 UTC


String of galaxies
©A Zitrin
A line of 14 galaxies seems to be strung along a filament of dark matter. This image, reconstructed from observations from the 40-inch Wise Observatory telescope in Israel, shows the relative positions of the galaxies, which lie about 2 million light years away. Blue regions are where the most stars are forming.

More than a dozen galaxies seem to be lined up along a bridge of dark matter inside a region of nearly empty space. This 'bridge to nowhere' could shed light on how small galaxies formed in the early universe.

Galaxies in the universe are arranged in a lacy structure that contains many holes, or voids, that are largely bereft of galaxies. But the voids are not completely empty; astronomers expect they are criss-crossed by filaments of dark matter.

Now, astronomers have found a total of 14 galaxies that appear to be part of a dark matter bridge at least 1.5 million light years long.
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Sherlock

Malaysian archaeologists find complete Neolithic skeletons: report


Agence France-Presse
Sat, 20 Sep 2008 14:34 UTC
Archaeologists have found two groups of complete Neolithic human remains in peninsular Malaysia and on Borneo island that may better explain prehistoric human life, reports said Friday.

Archaeologists say the remains are more than 3,000 years old and were found within two months of each other, in prehistoric burial grounds surrounded by ceremonial beads, pottery, shells and animal bones, the Sun daily reported.
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Info

Emergence Of Agriculture In Prehistory Took Much Longer, Genetic Evidence Suggests


Science Daily
Sat, 20 Sep 2008 14:33 UTC
Researchers led by Dr Robin Allaby of the University of Warwick's plant research arm Warwick HRI have found evidence that genetics supports the idea that the emergence of agriculture in prehistory took much longer than originally thought.

Image
©iStockphoto/Tomas Bercic
A new mathematical model shows how plant agriculture actually began much earlier than first thought. It also shows that useful gene types could have actually taken thousands of years to become stable.

Until recently researchers say the story of the origin of agriculture was one of a relatively sudden appearance of plant cultivation in the Near East around 10,000 years ago spreading quickly into Europe and dovetailing conveniently with ideas about how quickly language and population genes spread from the Near East to Europe. Initially, genetics appeared to support this idea but now cracks are beginning to appear in the evidence underpinning that model.
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Stop

Hadron Collider halted for months


BBC
Sat, 20 Sep 2008 14:30 UTC
The Large Hadron Collider near Geneva will be out of action for at least two months, the European Organization for Nuclear Research (Cern) says.

Part of the giant physics experiment was turned off for the weekend while engineers probed a magnet failure.

But a Cern spokesman said damage to the £3.6bn ($6.6bn) particle accelerator was worse than anticipated.
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