*Membership spots not really limited!
David Bird wrote:
So... Andrew Higgs, Noble Laureate?
*Membership spots not really limited!
David Bird wrote:
So... Andrew Higgs, Noble Laureate?
David Bird wrote:
You're right! Maybe I was thinking Andrew because he's a Scot.
In our recent look at exoplanets, we emphasized that it's not enough to simply know where a planet is relative to its host star. To understand the planet's properties, you have to know details about its atmosphere among other things. So researchers have done just that, imaging each of the members of a four-planet system called HR 8799, which is centered on a bright young star about 130 light years from Earth.
Their findings suggest that none of the planets' atmospheres look very much like any of the others, and only one of them looks like a member of our own solar system.
Nearly everything about HR 8799 and its surroundings is rather unusual. (The authors refer to all of it as an exosolar system, in parallel to the term exoplanet.) The star itself has been estimated to be as young as 30 million years old. It's only a bit more massive than the Sun, but quite a bit brighter, especially in the UV. It's also much more variable than the Sun, with large changes in its output occurring over the span of just a few days.
Scientists at NTT Basic Research Laboratories in Japan have boldly gone where no man has gone before by successfully constructing the world's first true "phaser," an emission of sound waves similar to a laser but without the aid of light. As Wired points out, the word "laser" stands for “light amplification by stimulated emission of radiation," therefore these new sound-based devices, utilizing particles called phonons, might aptly be termed "phasers" as it is far too tempting to not compound the term "phonon laser" into a single word.
While phonon lasers first made waves - if you will pardon the pun - in 2010, when researchers at Johns Hopkins pioneered the technology, this development marks the first time that they have been made to work without relying on a conventional photon-based laser to direct the emission of phonons.
NASA is working on plans to robotically capture and tow a small asteroid back to Earth's vicinity by the end of the decade, setting the stage for manned visits to learn more about the threat asteroids pose, the resources they represent and to help perfect the technology needed for eventual flights to Mars.
Louis Friedman, former director of the Planetary Society and a co-author of the original Keck study, said the proposed mission "is quite an exciting idea" that supports President Obama's 2010 call for sending astronauts to an asteroid.
"It turns out, a first mission to an asteroid is still a big step, too big a step, because you'd need a much larger launch vehicle than we're building, you'd need a crew support system that could last for at least nine months in space because of the round-trip time," Friedman said in a telephone interview. "If we have to wait for that, it would be a couple of decades.
"But the nice idea here is we can robotically move the asteroid closer to Earth and do the mission as soon as ... the 2020s, the goal is 2025. By moving the asteroid here, we have a much safer, earlier first step for humans going beyond the moon."
The mission has "both technical advantages and scientific advantages because we're actually exploring an object instead of going to empty space," he said. "It also has an excitement about it because we get the robotic mission, which is a very interesting idea, moving an asteroid close to Earth ... and then sending astronauts up to visit it."
The Keck study estimated a cost of about $2.65 billion to capture and return a carbonaceous asteroid roughly 20 feet across. NASA officials had no official comment Friday and the mission outline obtained by CBS News did not include cost estimates.
A study published Wednesday in The Journal of the Royal Society Interface details the scientists’ quest, including their discovery of how the bugs get hooked on the leaves, how the scientists have tried to recreate these hooks synthetically and how their artificial hooks have proved to be less successful than the biological ones.
But even though there is no indication that the bean leaves and the bedbugs evolved to work together, the leaves are fiendishly clever in exploiting the insects’ anatomy. Like the armor covering knights in medieval times, the bedbug’s exoskeleton has thinner areas where its legs flex and its tiny claws protrude — like the spot where a greave, or piece of leg armor, ends.
“The areas where they appear to be pierceable,” Dr. Loudon said, “are not the legs themselves. It’s where they bend, where it’s thin. That’s where they get pierced.”
The first task was to determine exactly how the hooks — the technical name is trichomes — worked. The process was viewed through an electron microscope, Dr. Loudon said. “The foot comes down onto the surface, but as it’s lifting up, it’s catching on these hooks,” she said. “The point is pointing down. So all of their legs get impaled.”
“And as soon as one leg gets caught,” she added, “they are rapidly moving legs around and try to get away on the surface. That’s when they get multiply impaled.”
Dr. Loudon and her co-authors — Megan W. Szyndler and Robert M. Corn from Irvine and Kenneth F. Haynes and Michael F. Potter of the University of Kentucky — then set out to mimic the mechanism.
Using a casting process similar to one a sculptor might choose, the scientists replicated, with polymers from different epoxies, the geometry of the trichomes, the sharp point on their tips and their flexibility and strength. Sometimes the tips of the hooks broke off during the molding process, resulting in a hybrid of biological and fabricated materials.
On the natural leaves, bugs were snagged, on average, after six steps, or locomotory cycles. (In one cycle, each of the insect’s six legs moves once.) Once stuck, they tried to free themselves, but they usually ended up just flailing in place around the impaled limb.
The bugs, however, were largely unimpeded by the synthetic surfaces. According to the study, it took them, on average, a Hitchcockian 39 steps to be momentarily snagged, but their armor was never pierced, and they usually moved on.
The rain may fall mainly from the rings of Saturn.
While it does not have the same ring to the phrase repeated by Eliza in My Fair Lady as she learned the importance of pronunciation, scientists have discovered that water is raining onto Saturn from its own distinctive rings.
The finding may help to explain where water seen in Saturn's upper atmosphere is coming from.
Observations taken by the Keck Observatory in Hawaii have shown that electrically charged droplets of rain are showering onto the planet from the rings 120,000 miles overhead.
James O'Donoghue, the lead author of the study at Leicester University, said: "“Saturn is the first planet to show significant interaction between its atmosphere and ring system.
"The main effect of ring rain is that it acts to ‘quench’ the ionosphere of Saturn, severely reducing the electron densities in regions in which it falls."
The findings are published in the journal [url=http://www.telegraph.co.uk/science/space/9985666/[http://www.nature.com/nature/journal/v496/n7444/full/nature12049.html]Nature[/url] and reveal that the water falls across a large portion of the planet, influencing the composition and temperature in the upper parts of Saturn's atmosphere.
Bigger blue crabs sound like exactly what evolution should produce if the human palate were the driver: A crustacean that rewards easier picking with more meat. Unfortunately for the hungry, the results of ocean acidification appear to be precisely the opposite, according to a report in The Washington Post.
The oceans are slowly getting more laden with the carbon produced when humans burn oil, gas and coal. Carbon not only makes ocean water more acidic, but it proves a fine building block for crabs and other crustaceans. Or at least their shells, which are largely composed of calcium carbonate.
The result is bigger crabs with tougher exoskeletons. And since so much of the crab's energy goes into the intense process of building a shell, molting and building another shell, relatively little meat results.
It gets even worse for diners.
Because the crabs are bigger and stronger, they are also better predators. And they like to eat oysters.
How a Leafy Folk Remedy Stopped Bedbugs in Their Tracks
Generations of Eastern European housewives doing battle against bedbugs spread bean leaves around the floor of an infested room at night. In the morning, the leaves would be covered with bedbugs that had somehow been trapped there. The leaves, and the pests, were collected and burned — by the pound, in extreme infestations.
Now a group of American scientists is studying this bedbug-leaf interaction, with an eye to replicating nature’s Roach Motel.
The new technique might make it possible for scientists to create food without the use of soil, fertilizer, pesticides or large amounts of water.
A team of researchers at Virginia Tech recently succeeded in transforming cellulose into starch, a process that could be used to find new nutrient sources from plants not traditionally thought of as food crops. And at 20 to 40 percent of a person’s daily caloric intake, starch is an important- and increasingly scarce- resource in today’s world.
The caveats, however, have led to a number of arguments over whether a given exoplanet is likely able to host liquid water, with some candidates shifting in and out of the habitable zone more than once. Still, it's pretty clear that given the large number of reported candidate exoplanets, the odds suggest we've already spotted one. Today, scientists are announcing an exosolar system that has two planets that are both likely to be within the habitable zone, along with three others that are closer to the host star.
The findings come from the Kepler mission, which is dealing with a backlog of roughly 2,000 planet candidates to sort through and confirm. Normally, confirmation requires observing changes in the light emitted by the host star, which gets dragged closer to and further from the Earth as the planets circle it. However, this method requires that the planets either be large or orbiting close to the star so that their gravitational influence is big enough to shift it.
The new exosolar system, Kepler-62, couldn't be confirmed that way, in part because the planets orbiting it are simply too small. Measured in terms of the Earth, the five planets are 1.31, 0.54, 1.95, 1.61, and 1.41 Earth radii, in order of their distance from the host star. These measurements make the second planet, Kepler-62c, one of the smallest exoplanets yet spotted. The researchers refer to it as a "hot Mars," due to its proximity to the host star.
To confirm that the changes in the star's light were likely caused by planets passing in front of it, the authors calculated the odds of the changes resulting from a variety of alternatives. These include things like a complex system of stars orbiting each other or a chance confluence of stars at different distances from Earth. In every case, a system of planets ended up being thousands of times more likely to be the cause of the light changes from Kepler-62.
Samples of 400-year-old plants known as bryophytes have flourished under laboratory conditions.
Researchers say this back-from-the-dead trick has implications for how ecosystems recover from the planet's cyclic long periods of ice coverage.
The findings appear in Proceedings of the National Academy of Sciences.
They come from a group from the University of Alberta, who were exploring an area around the Teardrop Glacier, high in the Canadian Arctic.
The glaciers in the region have been receding at rates that have sharply accelerated since 2004, at about 3-4m per year.
That is exposing land that has not seen light of day since the so-called Little Ice Age, a widespread climatic cooling that ran roughly from AD 1550 to AD 1850.
Scientists at the U.S. Department of Energy’s Argonne National Laboratory in Illinois and from three other countries have joined together to perform the unlikely feat of transforming liquid cement into liquid metal. Using laser beams and an aerodynamic levitator, the researchers were able to turn liquid cement into a semiconductor, a process that could lead to new ways of manufacturing electronics.
To accomplish this marvel of modern-day alchemy, scientists from the U.S., Germany, Finland, and Japan used a process known as electron trapping. The team melted mayenite, a rare calcium aluminum oxide mineral that is part of alumina cement, to a temperature of about 2,000 degrees Celsius (3,632 degrees Fahrenheit), using a piece of equipment called an aerodynamic levitator.
The levitator, heated by a carbon dioxide laser beam, pumped out inert gas that caused the mayenite to levitate. This kept the hot liquid mayenite from touching any surfaces and forming crystals. The scientists then allowed the mayenite to cool into a glassy state, which created a material that traps electrons in a way favoring conductivity. The end result: the transformation of cement into a semi-conductor with metal-like qualities.
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