Science & Technology
A team of McGill chemists have discovered that a technique known as photoacoustic infrared spectroscopy could be used to identify the composition of pigments used in art work that is decades or even centuries old. Pigments give artist's materials colour, and they emit sounds when light is shone on them.
Researchers working at Inchbonnie, a dairy-farming settlement about 60 kilometres from Greymouth that lies on the fault, dated wood from the dead podocarp, believed to be a matai, sitting in water at the southern end of Lake Poerua.
The dating was part of a series of investigations in the area in February 2008 to determine movement on the fault and how strain is transferred from it to the nearby Hope, Clarence and Kakapo faults at the western edge of the Marlborough Fault System.
Until now, the average annual horizontal slip rate of the Alpine Fault at Inchbonnie was believed to be about 10 millimetres a year.
The latest calculations, based on when the stump died as a result of an earthquake, show it is moving at an average 13.6mm a year, plus or minus 1.8mm. That equates to about an extra metre of movement each time the fault ruptures - about every 300 years.
The Alpine Fault is the boundary between the Australian and Pacific plates, which are moving past and pushing against each other, forcing the Southern Alps higher.
Magnetic minerals in 15-million-year-old rocks appear to preserve a moment when the magnetic north pole was rapidly on its way to becoming the south pole, and vice versa. Such "geomagnetic field reversals" occur every couple hundred thousand years, normally taking about 4,000 years to make the change. The Nevada rocks suggest that this particular switch happened at a remarkably fast clip.
Anyone carrying a compass would have seen its measurements skew by about a degree a week - a flash in geologic time. A paper describing the discovery is slated to appear in Geophysical Research Letters.
It is only the second report of such a speedy change in geomagnetic direction. The first, described in 1995 based on rocks at Steens Mountain, Oregon, has never gained widespread acceptance in the paleomagnetism community. A second example could bolster the theory that reversals really can happen quickly, over the course of years or centuries instead of millennia.
"We're trying to make the case that [the new work] is another record of a superfast magnetic change," says lead author Scott Bogue, a geologist at Occidental College in Los Angeles.
Macquarie University palaeobiologist Dr John Alroy used fossils to track the fate of major groups of marine animals throughout the earth's history.
He compiled data from nearly 100,000 fossil collections worldwide, tracking the fate of marine animals during extreme extinction events some 250 million years ago.
The findings, published this week in the international journal Science, showed a major extinction event was currently under way that had the potential to be more severe than any others in history.
"Organisms that might have adapted in the past may not be able to this time," Dr Alroy said.
"You may end up with a dramatically altered sea floor because of changes in the dominance of major groups. That is, the extinction occurring now will overturn the balance of the marine groups."
The research shows a combination of human behaviour and climate change could have devastating affects on species across the planet.
"When there's mass extinction all bets are off and anything could happen," Dr Alroy said.
"So what we're basically doing as the human species collectively is we're running this gigantic experiment with nature."
An asteroid mission requires a large-enough destination that astronauts could reach within a few months of launch from Earth, says Lindley Johnson, head of NASA's Near-Earth Object program in Washington. Other limits to such an ambitious undertaking include the viewing range of ground-based telescopes.
"They don't come all that close all that often," Johnson said at a NASA workshop on NEOs three weeks ago.
While NASA admits more knowledge about objects that pass within 28 million miles (45 million km) of Earth could increase the number of possible destinations, only two currently meet the guidelines set out by the space agency in its attempt to send a manned mission to an asteroid by 2025, a goal set by President Barack Obama. One of the asteroids could be reached in 2020 and the other in 2025.
Sucrose has long been used as an analgesic for newborns; but now a study published online today in the Lancet says that the sweetener has no effect on pain levels in the babies' brains.
"Sucrose seems to blunt facial expression activity after painful procedures, but our data suggest that it ... might not be an effective analgesic drug," they wrote.
Newborns can't really tell you exactly how much something hurts, so doctors have to judge by the babies' facial contortions. When babies are given sugar right before a procedure, their faces don't show the same anguished expression as they would otherwise.

As the solar wind encounters Mercury, it slows down, piles up and flows around the planet (gray ball). This figure shows the density of protons from the solar wind, as calculated by modeling of the planet's magnetic sheath, or magnetosphere. The highest density, indicated by red, is on the side facing the sun; yellow indicates a lower density, and dark blue is the lowest.
Really, though, the exosphere is constantly changing and being renewed with sodium, potassium, calcium, magnesium and other species that are liberated from Mercury's soil by barrages of particles. Because both these particles and Mercury's surface materials respond to sunlight, the solar wind, Mercury's own magnetic sheath (the magnetosphere) and other dynamic forces, the exosphere may not look the same from one observation to the next. Far from being dead, Mercury's exosphere is a place of amazing activity that can tell astronomers a lot about the planet's surface and environment.
Three related papers written by scientists at NASA's Goddard Space Flight Center in Greenbelt, Md., and their colleagues offer insight into the details of how the exosphere gets replenished and show that new modeling of the magnetosphere and exosphere can explain some intriguing observations of the planet. These papers are published as part of Icarus's September 2010 special issue devoted to observations of Mercury during the first and second flybys of the MESSENGER (short for MErcury Surface, Space ENvironment, GEochemistry, and Ranging) spacecraft.

The red giant carbon star CW Leonis as seen by the PACS and SPIRE cameras on board Herschel. The star itself is too bright to be seen well, but it is releasing material in a violent stellar wind, some of which is seen in a “bow shock” to the left of the star in this image.
Every recipe needs a secret ingredient. When astronomers discovered an unexpected cloud of water vapour around the old star CW Leonis in 2001, they immediately began searching for the source. Water is known to be present around several types of stars, but CW Leonis is a "carbon star" and therefore thought not to produce water. Initially they suspected the star's heat must be evaporating comets or even dwarf planets to produce the water.
Now, Herschel's PACS (Photodetector Array Camera and Spectrometer) and SPIRE instruments have revealed that the secret ingredient is ultraviolet light, because the water vapour is too hot to have come from the destruction of icy celestial bodies and is distributed throughout the stellar wind, including deep down near the surface of the star itself. This suggests that the water is being created by a previously unsuspected chemical process where ultraviolet radiation from interstellar space is breaking up the carbon monoxide and releasing oxygen atoms that can then react with hydrogen to form water molecules.
New evidence has been discovered that reinforces the panspermia thoery that the red rain which fell in India in 2001, contained cells unlike any found on Earth. Panspermia is the idea championed by physicist Fred Hoyle that life exists throughout the universe in comets, asteroids and interstellar dust clouds and that life of Earth was seeded from one or more of these sources.
In 1903, in the German journal Umschau, Svante Arrhenius removed the meteors from the equation. Instead, he wrote, individual spores wafted throughout space, colonizing any hospitable planet they lit on. Arrhenius named the theory panspermia.
A growing body of evidence suggests that it might be Hoyle and Arrhenius might have been correct.
For example, various insects such as have been shown to survive for months or even years in the harsh conditions of space. the Allen Hills Mars meteorite that some scientists believe holds evidence of life on Mars, is that its interior never rose above 50 degrees centigrade, despite being blasted from the Martian surface by an meteor impact and surviving a fiery a descent through Earth's opaque atmosphere.
"Spores," says Gerda Horneck, of DLR German Aerospace Center in Köln, "can withstand a variety of different hostile conditions: heat, radiation, desiccation, chemical substances, such as alcohol, acetone and others. They have an extremely long shelf life. This is because the sensitive material, the DNA, is especially packed and protected in the spores
In 2001, the inhabitants of Kerala in the southern India observed red rain falling during a two month period. One, Godfrey Louis, a physicist at nearby Cochin University of Science and Technology, intrigued by this phenomena, collected numerous samples of red rain to find out what was causing the contamination, perhaps sand or dust from some distant desert.
Egyptology professor and Department Chair John Darnell and his team worked their way through the previously unearthed site of Umm Mawagir in the western deserts of Egypt and discovered large piles of ash next to clay ovens, buried in the sand. At first, the team wondered why so many ovens were clustered so close together in the northern part of the town, far from areas where people lived. They realized the ovens must have been used for large-scale production, not private use, at the newly discovered site - once an oasis but now a no man's land.









