Science & TechnologyS


Meteor

Dinosaurs: End of Their World...


The Observer
Sun, 08 Feb 2009 14:33 UTC
So what really caused the dinosaurs to die out?

Crater
© GuardianSite of the meteorite strike.
Part of the mystery and allure of dinosaurs is their (relatively) sudden disappearance from the face of the Earth at the end of the Late Cretaceous epoch, 65m years ago. Many theories have been expounded to explain their sudden departure, with more fanciful ones including a build-up of methane from herbivorous dinosaur farts, mass blindness from cataracts, or an eradication of plantlife due to a global infestation of caterpillars.

It is, however, now widely accepted that the most likely cause of this mass extinction event (which, in fact, not only eradicated dinosaurs but 75% or more of all land-based animal species) is the impact of a huge meteorite that struck Earth around the coast of what is now the Yucatán peninsula in south-east Mexico.
Read More...
Meteor

New Potentially Hazardous Asteroid Discovered

Nancy Atkinson
Universe Today
Sat, 07 Feb 2009 14:23 UTC
Asteroids
© Robert HolmesImage where PHA 2009 BD81 (left) was discovered. PHA 2008 EV5 is on the right.
While observing a known asteroid on January 31, 2009, astronomer Robert Holmes from the Astronomical Research Institute near Charleston, Illinois found another high speed object moving nearby through the same field of view. The object has now been confirmed to be a previously undiscovered Potentially Hazardous Asteroid (PHA), with several possible Earth impact risks after 2042. This relatively small near-Earth asteroid, named 2009 BD81, will make its closest approach to Earth in 2009 on February 27, passing a comfortable 7 million kilometers away. In 2042, current projections have it passing within 5.5 Earth radii, (approximately 31,800 km or 19,800 miles) with an even closer approach in 2044. Data from the NASA/JPL Risk web page show 2009 BD81 to be fairly small, with a diameter of 0.314 km (about 1000 ft.) Holmes, one of the world's most prolific asteroid spotters, said currently, the chance of this asteroid hitting Earth in 33 years or so is quite small; the odds are about 1 in 2 million, but follow-up observations are needed to provide precise calculations of the asteroid's potential future orbital path.
Read More...
Magnify

New Insights into Scientific Theory on Motor Protein

Jo Kelly
Medical News Today
Sun, 08 Feb 2009 00:00 UTC
An international team of scientists led by the University of Leeds has shed new light on the little-understood motor protein called dynein, thought to be involved in progressive neurological disorders such as motor neurone disease.

Researchers from the University's Astbury Centre for Structural Molecular Biology and from the University of Tokyo have for the first time identified key elements of dynein's structure, and the winch-like mechanism by which it moves.

The research - funded by the Biotechnology and Biological Sciences Research Council and the Wellcome Trust - is published in the latest issue of Cell.
Read More...
Satellite

Russia's Progress digital cargo spacecraft 'buried' in Pacific


RIA Novosti
Sun, 08 Feb 2009 14:07 UTC
Moscow - Russia's new, digitally-controlled Progress M-01M series spacecraft was "buried" on Sunday at a "spaceship cemetery" in the southern Pacific, Mission Control said.

"The cargo spacecraft's remaining fragments fell into the Pacific Ocean after re-entry into the Earth's atmosphere is 11:19 a.m. Moscow time [81:49 GMT]," Mission Control said.

The Progress M-01M cargo spacecraft undocked on Friday from the International Space Station and served as a temporary space lab before its "burial" in the Pacific Ocean.
Read More...
Magnify

Digital scans of "Lucy" take pre-humans inside out


Reuters
Sun, 08 Feb 2009 02:54 UTC
Houston - Digital X-rays have turned Lucy, perhaps the world's best-known pre-human, inside out, and may answer questions about how our ancestors came down from the trees and walked, scientists said on Friday.

The team at the University of Texas in Austin, in collaboration with the Ethiopian government, completed the first high-resolution computed tomography or CT scan of the human ancestor, who lived 3.2 million years ago.

"These scans we've completed at the University of Texas permit us to look at the internal architecture -- how her bones are built," anthropology professor John Kappelman, who helped lead the work scanning all 80 pieces of the skeleton, told Reuters in an interview.
Read More...
Info

US: Underwater stones in Lake Michigan puzzle archeologists

James Janega
Chicago Tribune
Sat, 07 Feb 2009 22:49 UTC
Stones in Lake Michigan
© Chris DoyalUnderwater archeologist Mark Holley investigates a circle of stones on the Grand Traverse Bay floor near Traverse City, Mich. Scientists are not sure whether the stones were arranged by humans or natural forces
Debate unfolds: Man or nature?

Forty feet below the surface of Lake Michigan in Grand Traverse Bay, a mysterious pattern of stones can be seen rising from an otherwise sandy half-mile of lake floor.

Likely the stones are a natural feature. But the possibility they are not has piqued the interest of archeologists, native tribes and state officials since underwater archeologist Mark Holley found the site in 2007 during a survey of the lake bottom.

The site recently has become something of an Internet sensation, thanks to a blogger who noticed an archeological paper on the topic and described the stones as "underwater Stonehenge."
Read More...
Telescope

Stars Form At Record Speeds


Science Daily
Sat, 07 Feb 2009 20:52 UTC
Orion-KL region
© NASA, ESA, Robberto (STScI/ESA), Orion Treasury Project TeamThe level of star-forming activity in the Orion-KL region (marked by the rectangle) in the Orion nebula is comparable to that of the central region of J1148+5251, but confined to a much smaller volume of space.

When galaxies are born, do their stars form everywhere at once, or only within a small core region? Recent measurements of an international team led by scientists from the Max Planck Institute for Astronomy provide the first concrete evidence that star-forming regions in infant galaxies are indeed small - but also hyperactive, producing stars at astonishingly high rates.

Galaxies, including our own Milky Way, consist of hundreds of billions of stars. How did such gigantic galactic systems come into being? Did a central region with stars first form then with time grow? Or did the stars form at the same time throughout the entire galaxy? An international team led by researchers from the Max Planck Institute for Astronomy is now much closer to being able to answer these questions.
Read More...
Info

Large Hadron Collider may start up again in September

Matthew Chalmers
New Scientist
Sat, 07 Feb 2009 20:09 UTC
Large Hadron Collider's ring
© CERNA worker prepares a replacement magnet for the Large Hadron Collider's ring.

After spending a week in the French town of Chamonix thrashing out technical and logistical arguments (and fitting in the odd afternoon of skiing), 120 or so physicists from the CERN laboratory near Geneva have recommended a schedule for the restart of the Large Hadron Collider (LHC).

They say the 27-km machine will be ready for its first proton collisions at low energies in late 2009, and that it should be operated through the winter until autumn 2010 with a collision energy of 10 TeV to ensure the experiments collect enough data to get some new physics results.

Given that the LHC consumes as much electrical power as all the households in the region around Geneva, that will land CERN with an additional €8 million electricity bill if the recommendations from the Chamonix workshop are accepted by the lab's management on Monday.
Read More...
Blackbox

What's the point of being warm-blooded?

Nick Lane
New Scientist
Sat, 07 Feb 2009 18:41 UTC
Image
© Ted Kinsman / Photolibrary.comCouldn't the food that warm-blooded animals burn to stay toasty be put to better use?

If you stopped eating today, you wouldn't survive more than two months. A crocodile, on the other hand, might live for a year or more. Why the difference? You waste most of the food you eat generating heat.

The evolution of warm-bloodedness, or endothermy, is one of life's great mysteries. Sure, there are some advantages - staying active in the cold, keeping young cosy and warm, and avoiding having to go out into the open to soak up heat from the sun.

The thing is, you could get much the same advantages by turning up the heat only when and where in the body it is needed, as many animals do. So why do most birds and mammals keep the furnaces burning 24/7? Staying warm - which for birds means 40 °C on average - comes at a price. Some warm-blooded animals have to eat as much in one day as similarly sized reptiles do in a month, a dangerous and time-consuming strategy.
Read More...
Info

How the fetal brain wires up for action


New Scientist
Sat, 07 Feb 2009 17:28 UTC
Before a fetus is born, its brain undergoes the complex process of refining the connections between its different regions. Now a computer model is showing us how.

Although our genes provide an initial blueprint for the way different neurons connect together, the developing brain must still refine the wiring and prune out any redundant connections. "It's a big challenge to have a system that is ready by the time of birth so that newborns can begin experiencing the world right away," says Jean-Philippe Thivierge from Indiana University, Bloomington.

Neuroscientists suspect the brain achieves this by sending out waves of spontaneous electrical activity that cascade across groups of neurons, helping it to scout out the relative positions of neurons and forge the most efficient network.
Read More...