Science & TechnologyS


Star

Fundamental constant is pretty much constant

Jon Cartwright
Physorg
Sun, 24 Jun 2007 10:16 UTC
The idea that fundamental constants do not actually stay constant over space and time has long played on the mind of physicists. But by looking at how a distant galaxy has absorbed the light from a quasar, researchers in Australia have obtained a new limit on how much one fundamental constant -- the ratio of the electron and proton masses -- is changing with time. Their result, which is 10 times more accurate than previous measurements, gives the thumbs up to our current understanding of physics.
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Bulb

Sweet Dreams: Scientist Calls Mars a Terraforming Target for the 21st Century

Leonard David
Space.com
Sun, 24 Jun 2007 09:54 UTC
Mars will be transformed into a shirt-sleeve, habitable world for humanity before century's end, made livable by thawing out the coldish climes of the red planet and altering its now carbon dioxide-rich atmosphere.

How best to carry out a fast-paced, decade by decade planetary facelift of Mars - a technique called "terraforming" - has been outlined by Lowell Wood, a noted physicist and recent retiree of the Lawrence Livermore National Laboratory and a long-time Visiting Fellow of the Hoover Institution.

Lowell presented his eye-opening Mars manifesto at Flight School, held here June 20-22 at the Aspen Institute, laying out a scientific plan to "experiment on a planet we're not living on."
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Video

Hubble Photographs Two Huge Asteroids

Robert Roy Britt
Space.com
Sat, 23 Jun 2007 06:19 UTC
The Hubble Space Telescope has imaged two of the largest known asteroids, revealing craters and other features that will soon be the targets of close-up observations by NASA's Dawn spacecraft.

Ceres is round, like a planet, and 590 miles (950 kilometers) wide. The rock, about the size of Texas, contains some 30 to 40 percent of all the mass in the asteroid belt between Mars and Jupiter.

Thought to be a planet after its discovery in 1801, Ceres was later reclassified as an asteroid. But under the new and controversial planet definition that demoted Pluto, Ceres is now considered a dwarf planet.

Vesta, the other target, is irregularly shaped and about 330 miles (530 kilometers) wide-about the size of Arizona.
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Magic Wand

St. Jude study shows genes play an unexpected role in their own activation


EurekAlert
Sat, 23 Jun 2007 06:17 UTC
Investigators at St. Jude Children's Research Hospital have discovered how a single molecular "on switch" triggers gene activity that might cause effects ranging from learning and memory capabilities to glucose production in the liver.

The "on switch," a protein called CREB, is a transcription factor - a molecule that binds to a section of DNA near a gene and triggers that gene to make the specific protein for which it codes. CREB activates genes in response to a molecule called cAMP, which acts as a messenger for a variety of stimuli including hormones and nerve-signaling molecules called neurotransmitters.

The St. Jude team showed that each gene that responds to CREB chooses which co-factors, or helper molecules, CREB uses to activate that gene. This finding adds an important piece to the puzzle of how cells use CREB to activate specific genes in response to cAMP signals.

It also suggests that the current model scientists use to explain how CREB works is too simple, said Paul Brindle, Ph.D., associate member of the Department of Biochemistry at St. Jude. Brindle is senior author of a report on this work that appears in the June 20 issue of "The EMBO Journal."
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Wolf

Taking animals out of laboratory research


The University of Nottingham
Sat, 23 Jun 2007 06:11 UTC
Pioneering work to reduce the use of animals in scientific research - and ultimately remove them from laboratories altogether - has received a major boost at The University of Nottingham.

A laboratory devoted to finding effective alternatives to animal testing has been expanded and completely remodelled in a £240,000 overhaul designed to hasten the development of effective non-animal techniques.

Scientists hope that by developing the use of cell and tissue cultures, computer modelling, cell and molecular biology, epidemiology and other methods, they will one day be able to completely remove animals from medical research - while still maintaining crucial work to defeat diseases that affect millions of people.

The new FRAME Alternatives Laboratory, within the University's Medical School, is to be officially opened by Ed Balls MP, Economic Secretary to the Treasury, on July 6.
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Bulb

Geophysicists detect a molten rock layer deep below the American Southwest


Innovations report
Sat, 23 Jun 2007 05:12 UTC
A sheet of molten rock roughly 10 miles thick spreads underneath much of the American Southwest, some 250 miles below Tucson, Ariz. From the surface, you can't see it, smell it or feel it.

But Arizona geophysicists Daniel Toffelmier and James Tyburczy detected the molten layer with a comparatively new and overlooked technique for exploring the deep Earth that uses magnetic eruptions on the sun.
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Star

The Cosmic Horseshoe, a Nearly Complete Einstein Ring


Universe Today
Sat, 23 Jun 2007 05:00 UTC
If you want to peer into the furthest reaches of space, a regular telescope won't do. You need to harness the power of a massive galaxy to bend light from an even more distant galaxy - a gravitational lens. And a team of European astronomers have found one of the luckiest discoveries of all, an Einstein ring, where the lens and more distant galaxy line almost perfectly. Because of its unique shape, they're calling it "The Cosmic Horseshoe".

The discovery was made by more than a dozen astronomers from a handful of European universities, from England to Russia. They published their discovery in a research paper called The Cosmic Horseshoe: Discovery of an Einstein Ring around a Giant Luminous Red Galaxy, which has been submitted to the Astrophysics Journal.
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Clock

Mummies by demand: Three thousand year-old mummy discovered in Egypt


AFP
Sat, 23 Jun 2007 04:48 UTC
Archaeologists have discovered the 3,000-year-old mummy of a high priest to the god Amun in the southern city of Luxor, antiquities supremo Zahi Hawass told the official MENA news agency on Saturday.

The 18th Dynasty mummy of Sennefer was unearthed in a tomb in the Valley of the Kings -- one of the most famous archaeological sites in the world -- by a team from Britain's Cambridge University.

"The mummy was found in tomb 99 in the Valley of the Kings on the west bank of Luxor," Hawass said.
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Magnify

Has a Tunguska Crater Been Found?

David Tytell
Sky and Telescope
Fri, 22 Jun 2007 18:32 UTC
Here's a story that just hit our radar screen, and we wanted to share the news immediately rather than wait for further facts to come out. In the online journal Terra Nova, a team of Italian researchers led by marine geologist Luca Gasperini reports on what may be the missing Tunguska impact crater.

Comment: Here is the conclusion of the study cited above:
Cheko, a small lake located 8 km from the alleged epicentre of the 1908 Tunguska Event, has an unusual funnel-like bottom morphology, with 50 m maximum water-depth near the center and a 0.16 depth-to-diameter ratio. This morphology is different from that of subarctic Siberian thermokarst lakes, and is also hard to be accounted for other 'normal' Earth-surface tectonic or erosion/deposition processes, but is compatible with the impact of a cosmic body. Based on diameter, depth and morphology of the lake crater, and assuming that the impacting object was an asteroid, a mass of 1.5 × 106 kg (10 m diameter) was estimated for the projectile. However, this estimate is probably too large, because the crater was enlarged by permafrost melting and release of H2O, CH4 and other volatiles induced by the impact into a soggy ground. The projectile that formed Lake Cheko might have been a fragment of the main body that exploded in the atmosphere 5 - 10 km above ground. A prominent reflector observed in seismic reflection profiles 10 m below the bottom at the center of the lake indicates a sharp density/velocity contrast, compatible with either the presence of a fragment of the body, or of material compacted by the impact. Drilling could solve this dilemma.


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Coffee

NASA looks for break in weather to land shuttle


Reuters
Fri, 22 Jun 2007 13:48 UTC
NASA looked to Mother Nature for guidance on Friday as it sought for a second day to bring space shuttle Atlantis and seven astronauts home from a two-week-long mission.

The U.S. space agency said weather would decide if Atlantis lands at Kennedy Space Center in Florida or at back-up site Edwards Air Force Base in California.
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