Science & TechnologyS


Evil Rays

Weapons technology: Top 10 from 2008

Paul Marks
New Scientist
Wed, 31 Dec 2008 17:05 UTC
laser-based version of a light anti-armour weapon
© Ben Curtis/PA Archive/PAA soldier fires a laser-based version of a light anti-armour weapon during an exercise in Canada.
It's the stuff of science fiction: robots that can hunt down and kill humans, powerful lasers that can destroy targets without leaving a trace, and a weapon that can supposedly knock you down without even touching you - all of these, and more, came one step closer to reality in 2008.

The developers of these technologies say that they will help to ensure that modern warfare is as efficient and humane as possible. Their critics say the weapons are just the latest in a long line of lethal inventions that have increased man's brutality to man - successors to the Maxim automatic machine gun, the flame thrower, and mustard gas. Whichever view you take, they introduce new ethical and practical questions.

In this review, we have gathered the 10 most important stories that New Scientist published on this subject this year, so you can make up your own mind.

Airborne Laser lets rip on first target

Laser dogfights in the sky may not be such a long way off, after a megawatt laser weapon was fired from an aircraft for the first time. The plan is to target "rogue" missiles - but it could also be used against other planes or targets on the ground.

US boasts of laser weapon's 'plausible deniability'
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Camera

3-D Moon Imaging Inaugurated With NASA Instrument Aboard India's Chandrayaan-1 Spacecraft


Science Daily
Tue, 30 Dec 2008 22:58 UTC
moon's Orientale region
© NASA/JPL/BrownThe left figure is a color composite of processed data that accentuates compositional differences in the moon's Orientale region. The image on the right contains significant thermal emission in the signal and is particularly sensitive to small variations in local morphology.
Different wavelengths of light provide new information about the Orientale Basin region of the moon in a new composite image taken by NASA's Moon Mineralogy Mapper, a guest instrument aboard the Indian Space Research Organization's Chandrayaan-1 spacecraft.

The Moon Mineralogy Mapper is the first instrument to provide highly uniform imaging of the lunar surface. Along with the length and width dimensions across a typical image, the instrument analyzes a third dimension - color.

A two-image figure, and other data from NASA's Moon Mineralogy Mapper Instrument, can be found HERE.

The composite image consists of a subset of Moon Mineralogy Mapper data for the Orientale region. The image strip on the left is a color composite of data from 28 separate wavelengths of light reflected from the moon. The blue to red tones reveal changes in rock and mineral composition, and the green color is an indication of the abundance of iron-bearing minerals such as pyroxene. The image strip on the right is from a single wavelength of light that contains thermal emission, providing a new level of detail on the form and structure of the region's surface.
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Sun

Solar wind makes Earth's atmosphere fluctuate

Sid Perkins
Science News
Tue, 16 Dec 2008 22:46 UTC
Analyses of satellite data reveal that Earth's atmosphere expands and contracts in response to short-term variations in the solar wind. Understanding this previously unrecognized phenomenon and how it affects objects traveling in low-Earth orbits will enable scientists to better track satellites, and to track the space junk that threatens them.

Besides the more than 800 satellites in low-Earth orbit, more than 17,000 pieces of space junk also circle the planet, reported Jeffrey P. Thayer, an atmospheric scientist at the University of Colorado at Boulder, December 15 at the fall meeting of the American Geophysical Union.

Researchers have long known that variations in the amount of certain wavelengths of ultraviolet light emitted by the sun cause the planet's atmosphere to swell and shrink. The higher the amount of incoming UV radiation, the warmer the upper atmosphere becomes and the more it expands toward space, Thayer says.
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Magnify

Massive Volcanic Eruptions Could Have Killed Off the Dinosaurs

Betsy Mason
Wired
Mon, 15 Dec 2008 22:27 UTC
Huge volcanic eruptions that belched sulfur into the air for around 10,000 years could have killed the dinosaurs, according to new evidence unearthed by geologists.

Evidence is accumulating that it wasn't an asteroid that did the beasts in, but volcanoes -- the first real challenge the extinction theory has met in three decades.

A combination of studies on dinosaur fossils, magnetic signatures in rocks and the timing of the disappearance of different species suggest it was volcanoes, not an asteroid, that caused the dinosaurs' extinction.
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Meteor

Italian Sets Comet Sighting Record


Ansa.it
Mon, 29 Dec 2008 14:20 UTC
comet boattini
Astronomer Boattini spots seven in one year
Italian astronomer Andrea Boattini broke the record for the number of new comets sighted in one year when he spotted his seventh at Christmas.

The previous record had been held for some 150 years by Italian astronomers Francesco De Vito and Giovanni Battista Donati who in the mid-1800s sighted six comets in one year.

The new comet has the technical tag C/2008 Y1 but like the others has also been given its discoverer's name.
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Meteor

Did A Comet Cause The Carolina Bays?

Liza Roberts
Raleigh Metro Magazine
Tue, 30 Dec 2008 19:36 UTC
George Howard is many things. He is the president of the Raleigh-based Restoration Systems mitigation bank and a conservationist; he is a history buff, a science geek, a cartographer. The 42-year-old family man is a talented amateur artist, a dedicated if unprolific fisherman and a politico whose office photos show him chummy with folks including Jesse Helms, Newt Gingrich, Lauch Faircloth and both George Bushes.
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Meteor

Meteorite Strikes, Setting Off a Tsunami: Did It Happen Here?

Kenneth Chang
New York Times
Tue, 30 Dec 2008 19:26 UTC
The tsunami washed over Fire Island and, to the west, waves perhaps as high as 20 feet spilled into Lower Manhattan. The furious onrush of water left sediment a foot and a half deep on the Jersey Shore, and debris cascaded far up the Hudson River.
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Magnify

Drilling Holes Through Deadly Bacteria's Kevlar-like Hide


Science Daily
Mon, 29 Dec 2008 19:41 UTC
Image
© Rockefeller UniversitySeeing through walls. An experiment shows that when dividing strep bacteria are stripped of their surface proteins (left), they begin to grow back in just minutes. One surface protein, protein M (green), anchors to the spot where sortase A (red) assembles. Before the bacteria finish dividing (right), sortase A has already begun to migrate to the new site of division.
To protect themselves from human defenses, disease-causing bacteria have evolved a cell wall made from a nearly impenetrable tangle of tightly woven strands. That's made it difficult for scientists to see what goes on inside these potentially deadly organisms. But that era is now over. Rockefeller University researchers have now figured out how to drill holes through the Kevlar-like hide of gram-positive bacteria without obliterating them, and in doing so, they've made it possible to study, from the inside out, most of the known bacteria on the planet.

The work, led by Vincent A. Fischetti, head of the Laboratory of Bacterial Pathogenesis and Immunology, provides, for the first time ever, a look inside the rapidly multiplying and highly contagious Streptococcus pyogenes, the culprit behind a myriad of diseases, including strep throat and rheumatic fever. At a time when organisms are increasingly acquiring "superbug" powers, Fischetti and his colleague Assaf Raz, a graduate student in the lab, have used the technique to look specifically at a well-known enzyme called sortase A and its distribution inside the cell. Common to all gram-positive bacteria, the enzyme functions by anchoring surface proteins to the cell wall, endowing the bacteria with their infectious properties.
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Info

How Helium Can Be Solid And Perfect Liquid At Same Time


Science Daily
Mon, 29 Dec 2008 19:35 UTC
Image
© M. TroyerPerfect helium crystals are normal classical crystals in which the atoms are localised at their lattice positions. At the point of a crystal defect, such as the grain boundary shown in the image, quantum mechanical effects cause the atoms to lose their exact position. They become delocalized and can flow along the defect without any friction: a "supersolid" is formed, a solid that is also a perfect liquid at the same time.
At very low temperatures, helium can be solid and a perfect liquid at the same time. Theoreticians, though, have incorrectly explained the phenomenon for a long time. Computer simulations at ETH Zurich have shown that only impurities can make this effect possible.

Matthias Troyer and his team carry out experiments at their computers. Troyer is Professor of Computational Physics at ETH Zurich's Institute of Theoretical Physics. He simulates quantum phenomena such as "supersolid" structures. Supersolidity describes a physical phase which can occur at very low temperatures and where a material appears to be solid and "superfluid" at the same time.

Enquiries from the armed forces

However, the word can be misunderstood, as was discovered by one of Troyer's colleagues who works on the phenomenon in the USA. The US Navy thought that "supersolid" meant "extremely hard" and so asked the physicist whether such a material could be used to armour ships or at least put into a spray can or be used to kill someone. The physicist answered "No" - because "supersolid" does not mean super-hard. After that, the army showed no further interest.
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Meteor

Flashback Committee Report 17 of 50 - House Report 109-354 - National Aeronautics And Space Administration Authorization Act Of 2005

George E. Brown
The Library of Congress
Mon, 29 Dec 2008 08:49 UTC
SEC. 321. GEORGE E. BROWN, JR. NEAR-EARTH OBJECT SURVEY.

(a) Short Title- This section may be cited as the 'George E. Brown, Jr. Near-Earth Object Survey Act'.

(b) Findings- The Congress makes the following findings:
(1) Near-Earth objects pose a serious and credible threat to humankind, as many scientists believe that a major asteroid or comet was responsible for the mass extinction of the majority of the Earth's species, including the dinosaurs, nearly 65,000,000 years ago.

(2) Similar objects have struck the Earth or passed through the Earth's atmosphere several times in the Earth's history and pose a similar threat in the future.

(3) Several such near-Earth objects have only been discovered within days of the objects' closest approach to Earth, and recent discoveries of such large objects indicate that many large near-Earth objects remain undiscovered.

(4) The efforts taken to date by NASA for detecting and characterizing the hazards of near-Earth objects are not sufficient to fully determine the threat posed by such objects to cause widespread destruction and loss of life.
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