Dead Stars 'to Guide Spacecraft'
|6:47:26 PM, Sunday, April 01, 2012|
“(By Jonathan Amos, Science correspondent, BBC News) Spacecraft could one day navigate through the cosmos using a particular type of dead star as a kind of GPS.
German scientists are developing a technique that allows for very precise positioning anywhere in space by picking up X-ray signals from pulsars.
These dense, burnt-out stars rotate rapidly, sweeping their emission across the cosmos at rates that are so stable they rival atomic clock performance.
This timing property is perfect for interstellar navigation, says the team.
If a spacecraft carried the means to detect the pulses, it could compare their arrival times with those predicted at a reference location. This would enable the craft to determine its position to an accuracy of just five kilometres anywhere in the galaxy.
"The principle is so simple that it will definitely have applications," said Prof Werner Becker from the Max-Planck Institute for Extraterrestrial Physics in Garching.
"These pulsars are everywhere in the Universe and their flashing is so predictable that it makes such an approach really straightforward," he told BBC News.
Prof Becker has been describing his team's research here at the UK National Astronomy Meeting in Manchester.
The proposed technique is very similar to that employed in the popular Global Positioning System, which broadcasts timing signals to the user from a constellation of satellites in orbit.
But GPS only works on, or just above, the Earth so it has no use beyond our planet.
Currently, mission controllers wanting to work out the position of their spacecraft deep in the Solar System will study the differences in time radio communications take to travel to and from the satellite. It is a complex process and requires several antennas dotted across the Earth.
It is also a technique that is far from precise, and the errors increase the further away the probe moves.
For the most distant spacecraft still in operation - Nasa's Voyager satellites, which are now approaching the very edge of the Solar System, some 18 billion km away - the errors associated with their positions are on the order of several hundred km.
Even for a probe at the reasonably short separation of Mars, the positioning uncertainty can be about 10km.
It is unlikely though that navigation by pulsar beacon will find immediate use.
The telescope hardware for detecting X-rays in space has traditionally been bulky and heavy.
Engineers will need to miniaturise the technology to make a practical pulsar navigation unit.
"It becomes possible with the development of lightweight X-ray mirrors," said Prof Becker.
"These are on the way for the next generation of X-ray telescopes. Current mirrors have a 100 times more weight and would be completely unusable.
"In 15-20 years, the new mirrors will be standard and our device will be ready to be built."
The scientist believes his navigation solution will certainly find use on Solar System probes, providing autonomous navigation for interplanetary missions and perhaps for future manned ventures to Mars where high performance systems will be an absolute requirement for safety reasons.
But he also likes the idea of humanity one day pushing out across interstellar space.
"You know for GPS that if you go to another country, you have to buy the maps for your device. Well, we were joking with our students in Garching about selling maps for different galaxies for ships like Enterprise [on Star Trek]."”
Oldest Alien Planets Found—Born at Dawn of Universe
|7:22:07 PM, Saturday, March 31, 2012|
“(Nat. Geo.) Two huge planets found orbiting a star 375 light-years away are the oldest alien worlds yet discovered, scientists say.
With an estimated age of 12.8 billion years, the host star—and thus the planets—most likely formed at the dawn of the universe, less than a billion years after the big bang.
"The Milky Way itself was not completely formed yet," said study leader Johny Setiawan, who conducted the research while at the Max-Planck Institute for Astronomy in Heidelberg, Germany.
During a recent survey, Setiawan and colleagues found the signatures of the two planets orbiting the star, dubbed HIP 11952.
Based on the team's calculations, one world is almost as massive as Jupiter and completes an orbit in roughly seven days. The other planet is nearly three times Jupiter's mass and has an orbital period of nine and a half months.
It's possible the planets are much younger than they seem if the worlds formed long after their star was born—but such a scenario is unlikely, the team says.
"Usually planets form just shortly after the star formation," Setiawan said. "Second-generation planets might also form after a star has died, but this is still under debate."
Ancient Planets Defy Theory
Setiawan and colleagues found the ancient planets using a technique called radial velocity, in which astronomers watch for periodic wobbles in a star's light due to the gravitational tugs of orbiting worlds.
The discovery indicates that planet formation in the early universe was possible despite the fact that stars in existence back then were metal-poor—the astronomy term for stars lacking in elements heavier than hydrogen and helium.
In the case of HIP 11952, "its iron abundance is only about one percent that of our sun," Setiawan said.
The idea of planets springing from such a stellar makeup runs counter to a widely accepted theory called the accretion model, which says that heavy elements are needed to form planets.
Even gas giants like Saturn and Jupiter require heavy elements to take shape, the thinking goes, because they are built upon solid cores.
The accretion theory has so far been backed up by observations: Most of the planet-harboring stars discovered to date are relatively young and have moderate to high amounts of metals.
But there may be an observational bias, Setiawan said: Astronomers may think the accretion model is correct because planet hunters have been targeting mostly young, sunlike stars.
"To verify this issue, it is necessary to do a planet-search survey around [older] metal-poor stars," Setiawan said.
Clock Ticking for Oldest Worlds
Despite the newfound planets' longevity, it's unlikely the worlds will survive for another 13 billion years.
The parent star will soon transform into a red giant, Setiawan said, one of the last stages of a sunlike star's life.
During this stage, the star will swell in size and most likely engulf any nearby planets.”
Lamborghini Batman is Pulled Over in Maryland
|7:56:09 AM, Saturday, March 31, 2012|
"There really should be more Superheroes in the real world, and it seems like this unnamed wealthy philanthropist agrees. He has taken it upon himself to give some sick kids in the hospital a very special visit.
The man was first seen a few days ago, in full Batman regalia, pulled over by Montgomery County Maryland Police. He was standing next to a black convertable Lamborghini Gallardo with yellow detailing, which doubles as this generous caped crusader’s Batmobile.
The story that unfolded revealed that he was apparently pulled over because his Batmobile did not have plates on it. He allegedly had the plates in the car, but was unable to make them fit in the Lamboghini’s plateholder.
Why he was still in the Batman suit was simply for convenience. The latex outfit is difficult to get in and out of, so he wears it to his appearance and changes out of it at home.
I imagine if I was incredibly wealthy I would have a hot car too. But this guy goes one step beyond, spending his spare time putting a smile on the face of some young unfortunate soul in the hospital. He’s a true Batman if there ever was one."
Simulations Unravel Mysteries of 2009 Jupiter Impact
|6:46:34 PM, Friday, March 30, 2012|
“(PhysOrg.com) -- During July of 1994, both amateur and professional astronomers were captivated as comet Shoemaker/Levy 9 broke apart and slammed into the atmosphere of Jupiter. While these types of impacts are generally rare, a second impact event occurred fifteen years later in July of 2009. The object responsible for the 2009 impact was not directly observed, so astronomers could only make inferences about the object based on the disturbances in the Jovian atmosphere, as shown in the image above.
New research by Jarrad Pond (University of Central Florida), and a team from the University of Central Florida and University of California, Santa Cruz aims to help determine the object responsible for the 2009 impact on Jupiter. Without a direct observation of the event, the team used numerical simulations in order to better understand the object responsible for the large disturbance of the Jovian atmosphere.
Using three dimensional hydrodynamics code, the team modeled the impacts of eight simulated impactors. The team used impactors of .5 and 1km, with different densities and compositions (basalt or ice). By using the same impact angle (69 degrees) and impact velocity 61.4 km/sec), the team was able to narrow down the potential size and composition of the object responsible for the July 2009 impact…”
-- This is an unusually image heavy article for PhysOrg.com, follow the link for the rest of the article.
Einstein Proved Correct on View of the Universe
|6:35:27 PM, Friday, March 30, 2012|
“(telegraph.co.uk) The new test of Einstein's view of the universe has proved him right with ''incredible accuracy'' and is helping scientists to understand the mysterious acceleration of the universe.
A team of cosmologists have announced at the National Astronomy Meeting being held at the University of Manchester, the most accurate measurement ever made from when the expansion of the universe began to accelerate.
It means that the phenomenon can be explained using just Einstein's general theory of relativity and the cosmological constant - the simplest theoretical explanation for the acceleration of the universe.
The results will be used to understand what is causing the acceleration and why, and will shed new light on dark energy - the name adopted for the fundamental agent driving the acceleration about which little is known.
The cosmologists from the University of Portsmouth and the Max Planck Institute for Extraterrestrial Physics have examined the period between five and six billion years ago when the universe was almost half its present age and made measurements of extraordinary accuracy - within 1.7 per cent.The findings support Einstein's general theory of relativity which predicts how fast galaxies, separated by large distances, should be moving toward one another and at what rate the structure of the universe should be growing.
The conclusions are consistent with the concordance model of a universe that bloomed from the big bang 13.7 million years ago.
Team member Dr Rita Tojeiro said: ''The results are the best measurement of an intergalactic distance ever made, which means cosmologists are closer than ever to understanding why the universe's expansion is accelerating.
''One of the great things about Einstein's general theory of relativity is that it is testable. Our results support the theory and are fully consistent with the notion that constant vacuum energy - empty space creating a repulsive force - is driving the acceleration of the universe.
''These are profound statements that describe the physics of our universe at the most fundamental level.
''Critically, the results find no evidence that dark energy is simply an illusion stemming from our poor understanding of the laws of gravity - Einstein's theory has passed its most stringent test yet at extra-galactic scales.''
The experiment was designed to follow up on an observation made in 1998, when scientists studied the brightness of mighty stellar explosions to deduce that the universe's expansion is, against all odds and against our understanding of fundamental physics, becoming increasingly fast.
The new discoveries are based on work by a collaboration of astronomers from across the globe representing the Baryon Acoustic Oscillation Spectroscopic Survey (BOSS), part of the third Sloan Digital Sky Survey (SDSS-III), which is mapping the three-dimensional positions of more than one million galaxies.
Professor Will Percival, head of this team at the university's Institute of Cosmology and Gravitation, said: ''Dark Energy was only discovered 14 years ago, and there's this feeling that we are still riding the wave of discovery.
''It's a very exciting time to be a cosmologist.''
Meanwhile, Einstein's brain has gone on show as a star attraction at an exhibition of human brains.
Other brains on display at The Wellcome Trust, London, include those of Charles Babbage and William Burke.
The exhibition, Brains: the mind as matter, includes more than 150 objects such as rare images of real brains, artworks, manuscripts, artefacts, videos and photography.
Curator Dr Marius Kwint, art historian and University of Portsmouth lecturer in visual culture, said: ''The exhibition shows how a single, fragile organ has become the object of modern society's most profound hopes, fears and beliefs, and some of its most extreme practices and advanced technologies.
''The different ways in which we have treated and represented real, physical brains open up a lot of questions about our collective minds.
''The brain is the most complex entity in the known universe and the exhibition is a fascinating exploration of how humans have tried to come to terms with this infinitely mysterious organ.''”
World Water Day
|6:08:20 PM, Friday, March 30, 2012|
"March 22, is World Water Day, an event established by the United Nations in 1993 to highlight the challenges associated with this precious resource. Each year has a theme, and this year's is "Water and Food Security." The UN estimates that more than one in six people worldwide lack access to 20-50 liters (5-13 gallons) of safe freshwater a day to ensure their basic needs for drinking, cooking, and cleaning. And as the world's population grows beyond 7 billion, clean water is growing scarcer in densely populated areas as well as in remote villages. Collected here are recent images showing water in our lives -- how we use it, abuse it, and depend on it."
-- I know I'm late, but the photos and the message are too good not to share! Follow the link and check them out.
Say Hello to an Extraterrestrial Ocean, the Enceladan Ocean, - and Maybe Extraterrestrial Life
|3:14:09 PM, Friday, March 30, 2012|
“(TIME Science) It's hard enough for kids to remember all the known oceans and seas — Atlantic, Pacific, Indian, Norwegian, Barents — and now they can add one more to the list: the Enceladan Ocean. The name is lovely, and the place is nifty, but there's not much chance of visiting it soon. It's located on Enceladus, one of Saturn's 66 known moons. While Enceladus has been familiar to us since it was first spotted in 1789, the discovery of its ocean, courtesy of the venerable Cassini spacecraft, is a whole new and possibly game-changing thing.
Enceladus has always been thought of as one of the more remarkable members of Saturn's marble bag of satellites. For one thing, it's dazzlingly bright. The percentage of sunlight that a body in the solar system reflects back is known as its albedo, and it's determined mostly by the color of the body's ground cover. For all the silvery brilliance of a full moon on a cloudless night, the albedo of our own drab satellite is a muddy 12%, owing mostly to the gray dust that covers it. The albedo of Enceladus, on the other hand, approaches a mirror-like 100%.
Such a high percentage likely means the surface is covered with ice crystals — and, what's more, that those crystals get regularly replenished. Consider how grubby and gray a fresh snowfall becomes after just a couple of days of splashing road slush and tromping people. Now imagine how a moon would look after a few billion years of cosmic bombardment by incoming meteors.
When the Voyager probes barnstormed Enceladus in 1982, they found that the moon is indeed covered in ice and being constantly repaved. Vast valleys and basins were filled with fresh, white cosmic snow. Craters were cut clean in half, with one side remaining visible and the other covered over. Most remarkably, Enceladus orbits within Saturn's E ring — the widest of the planet's bands — and just behind the moon is a visible bulge in the ring, the result of the sparkly exhaust from ice volcanoes that trails Enceladus like smoke from a steamship. It's that cryovolcanism that's responsible for the regular repaving.
In 2008, Cassini confirmed that the cryovolcanic exhaust is ordinary water, filled with carbon dioxide, carbon monoxide, potassium salts and other organic materials. Tidal pumping — or gravitational squeezing — by Saturn and the nearby sister moons Tethys and Dione keeps the interior of Enceladus warm, its water deposits liquid and the volcanoes erupting. The big question was always, How much water is there? A lake? A sea? A globe-girdling ocean? The more there is and the more it churns and circulates, the likelier it is that it could cook up some life.
The answer to that question finally came this week, thanks to Cassini images of stress cracks known as tiger stripes in the ice on the Enceladan surface. Cassini scientists were particularly interested in a pair of tiger stripes in the moon's warmer polar regions, since they are very deep and comparatively wide and seem to change over time.
The new images revealed that the cracks indeed widen and narrow and do so more than was once thought. The two sides of the cracks also move laterally relative to each other, the same way the two banks of the San Andreas Fault can slide forward and back and in opposite directions. And the greatest shifting, as expected, occurs after Enceladus makes its closest approach to Saturn.
"This new work gives scientists insight into the mechanics of these picturesque jets," says Terry Hurford, a Cassini associate at NASA's Goddard Space Flight Center. "[It] shows that Saturn really stresses Enceladus."
The fact that Enceladus becomes as dramatically distorted as it does is a powerful indicator of just how much water it contains. A watery world, after all, is a flexible world, and for Enceladus to be so elastic, it must contain a very large local ocean or perhaps even a globe-girdling one. Portions of that ocean may be not just bathwater warm but outright hot.
Enceladus is not the only moon in the solar system that is home to such a feature. Jupiter's Europa is even more certain to contain a global ocean of its own. On both worlds, organics plus water plus warmth plus time could be more than enough to get biology going.
"Cassini's seven-plus years ... have shown us how beautifully dynamic and unexpected the Saturn system is," says project scientist Linda Spilker at NASA's Jet Propulsion Laboratory. The idea that that system might also be a living one has just become a little more plausible.”
It Might be ‘Snowing Microbes’ on One of Saturn’s Moons
|9:53:00 PM, Thursday, March 29, 2012|
“A NASA scientist says there's a good chance of finding extraterrestrial life inhabiting one of Saturn's tiny orbiting moons.
"More than 90 jets of all sizes near Enceladus's south pole are spraying water vapor, icy particles, and organic compounds all over the place," says Carolyn Porco, an award-winning planetary scientist and leader of the Imaging Science team for NASA's Cassini spacecraft. "Cassini has flown several times now through this spray and has tasted it. And we have found that aside from water and organic material, there is salt in the icy particles. The salinity is the same as that of Earth's oceans."
NASA says the watery jets are erupting through icy cracks in a "vast underground sea" on this moon's surface. And the sea may be home to microbes similar to those found in some of the deepest parts of our own planet's oceans. While there is no direct sunlight reaching beneath the surface, Saturn's own orbit may be creating enough heat beneath the surface of Enceladus to helped create the tiny life-forms.
When filmmaker James Cameron returned from his historic voyage to the bottom of the Mariana Trench this week, he said the virtually unexplored depths reminded him of an isolated lunar landscape.
But since the watery jets of Enceladus are spewing with enough velocity to reach into outer space, astronauts may not even need to make a heralding voyage to Enceladus, or beneath its icy surface.
"It's erupting out into space where we can sample it. It sounds crazy but it could be snowing microbes on the surface of this little world," Porco said. "In the end, it is the most promising place I know of for an astrobiology search. We don't even need to go scratching around on the surface. We can fly through the plume and sample it."
Life's Building Blocks May Have Formed in Dust Around Young Sun
|7:33:28 PM, Thursday, March 29, 2012|
“(SPACE.com) The organic molecules that were the building blocks for life on Earth could have formed in the dusty disk that surrounded our sun before the solar system had planets, a new computer model shows. What's more, the study suggests the process would be the same around other stars that acquired planets, which means some of those worlds, too, could be seeded with the pieces necessary for life.
Geophysicist Fred Ciesla and astrobiologist Scott Sandford showed in their computer model how the orbiting dust that provided the raw material for planets, asteroids and comets could have been exposed to the ultraviolet light needed to develop organic molecules.
"The origin of these organics has been a mystery," Ciesla told SPACE.com. "There have been a number of places where they have been thought to have formed, and none are mutually exclusive."
Scientists think Earth and the solar system's other planets were formed around 4.5 billion years ago, in a process that began with tiny grains of dust colliding into each other as they orbited the sun, sticking together, forming chunks of rock and gradually building up more and more mass until gravity took over, pulling the chunks together.
Ciesla, of the University of Chicago, and Sandford, of NASA's Ames Research Center in Moffett Field, Calif., built a computer model of this protoplanetary disk of dust grains to test whether organic molecules could have formed there.
Organic compounds include basic molecules such as carbon and nitrogen, as well as more complex forms, such as amino acids and the nucleobases that form DNA and RNA.
Sandford had conducted previous experiments in the lab with sub-millimeter-size dust grains covered in ice. When these are exposed to the photons of ultraviolet light, Sandford found, the photons can break down the molecular bonds in the material, allowing atoms to recombine into more complex molecules.
Scientists were unsure, however, whether enough ultraviolet photons would have penetrated into the early sun's protoplanetary disk to allow organics to form there.
Ciesla and Sandford's model showed this wasn't a problem. In fact, the disk seems to have been dynamic enough that dust grains easily would be lofted onto the outer edges of the disk, where they would be exposed to the ultraviolet light from the sun necessary to form the complex molecules.
"It was exciting for us because it just fell out naturally," Ciesla said. "We didn't have to invoke any special conditions in our model. We just found everything we hoped would work out worked out perfectly."
That means it also should work out well around other stars.
"The dynamics and the processes that we've put in the model here, we don't expect them to be unique to our solar system," Ciesla said. "We expect this to be present in all planet-forming disks."
Still, the fact that organics could have formed in the disk doesn't explain exactly how they got onto Earth. When Earth formed, it would have been a molten mess, with temperatures high enough to destroy any organics present at the time.
However, scientists say organic compounds could have survived on the asteroids and comets left behind in the solar system after the planets formed. As these bodies pummeled the Earth over the eons, they could have deposited the building blocks for life.
The new findings are detailed in the March 30 issue of the journal Science.”
Up All Night on NASA's Flying Telescope
|4:30:00 PM, Thursday, March 29, 2012|
“The new SOFIA observatory isn't your average NASA project. Engineers took a 30-year old 747 airplane, cut a hole in the side and installed a 17-ton telescope. Most telescopes are either on the ground or somewhere in orbit, but SOFIA falls somewhere in the middle, flying around at about 40,000 feet.
I got the chance to hitch a ride on one of its recent research flights as the plane left Moffett Field at theNASA Ames Research Center. It's definitely not the kind of flight where you get a bag of peanuts and movie.
The researchers take advantage of the nighttime sky, so we left at dusk for 10-hour tour flying zigzags across the Pacific Ocean. Each leg of the journey is carefully calculated so the telescope can pinpoint a far away star. The plane interior is packed with computers and equipment. It also lacks insulation since much of it was removed to install the telescope, so it's both cold and loud inside.
At four in the morning, the astronomers are still hard at work. If they're as tired as I am, they certainly aren't showing it.
"For me, this is very exciting," says Ian McLean, a professor at the University of California-Los Angeles. He usually works on the ground. "All my career has been ground-based astronomy. So, it's only my second flight."
McLean says there's a good reason to do astronomy in the stratosphere. The atmosphere is thinner, which means it's easier for the telescope to see the stars. "It's almost as good as space," says McLean. "Not quite, but almost."
And unlike the Hubble Space Telescope, this telescope lands everyday, which means the scientists can update and fix the equipment. "By the time you get a mission into orbit, the technology you're using is relatively old. Here we can stay state of the art all the time," says McLean. NASA began developing SOFIA in 1997 and almost cancelled the project at one point. It flew its first science mission in November 2010 and now costs about $80 million a year to operate.
Searching for a "Holy Grail"
McLean says the SOFIA telescope could show astronomers something that's considered a Holy Grail in their field: seeing a star being born. It happens in huge, dusty clouds – stellar nurseries, as Mclean calls them. "The cloud is huge, light years across and it's gradually contracting to form a whole nursery of stars."
But there's a problem. Astronomers can't see what's happening inside the clouds because, once again, they're made of dust and it's hard to see through.
"We don't mean dust bunnies, but we mean little, tiny little grains of solid material. Doesn't matter how big a telescope you have, you can't see inside it," McLean says.
That's why SOFIA looks at a special kind of light called infrared light. If you look through a telescope on the ground, you're looking at the visible light from space – the light our eyes can see. Infrared light is invisible to us, but it penetrates space dust, which means the telescope can see through the dust too.
"You get to see what you can't see with your eye. It's like a window has been opened," says McLean. They're looking for exactly how stellar nurseries give birth to young stars. McLean says catching a star as it's forming can reveal clues about how own solar system formed.
But star birth isn't the only thing these researchers want to see. They're also looking at the way stars die.
A Star on the Way Out
As the plane makes as sharp right turn, the telescope focuses on an object called NGC 7027. It's a planetary nebula – also known as a dying star. McLean and his team are capturing an infrared image of the nebula, which is about 3,000 light years away. They can also see what it's made of.
"It has a distinctive shape. It's oval. There's a hole in the middle and that's because it literally is a shell of gas that came off the star," says McLean.
7027 is dying because the star has run out of fuel – the same fate that our sun will face in about five billion years. As it dies, the star casts off its outer layers, shedding huge amounts of material to form a cloud around it. But it's not entirely a sad story.
"It won't be wasted," says McLean. "The material that was thrown off by that star in its dying phase, somewhere, millions, perhaps billions of years from now, will find its way into a new star and the planets that form around it."
From dead stars come new stars – and planets like our own. The oxygen and nitrogen in our bodies were once formed inside a star. "The cosmos is within us," as astronomer Carl Sagan once said. "We're made of star stuff."
As sky begins to lighten, we descend towards the Dryden Aircraft Operations Facility in the Mojave Desert, where the plane is based. The SOFIA telescope is now undergoing service upgrades and then will return to the skies three times a week. Astronomers from around the world are lining up to get on board.”
Pesticides Hit Queen Bee Numbers
|4:11:37 PM, Thursday, March 29, 2012|
“(BBC) Some of the world's most commonly used pesticides are killing bees by damaging their ability to navigate and reducing numbers of queens, research suggests.
Scientific groups in the UK and France studied the effects of neonicotinoids, which are used in more than 100 nations on farm crops and in gardens.
The UK team found the pesticides caused an 85% drop in queen production.
Writing in the journal Science, the groups note that bee declines in many countries are reducing crop yields.
In the UK alone, pollination is calculated to be worth about £430m to the national economy.
And the US is among countries where a succession of local populations has crashed, a syndrome known as Colony Collapse Disorder.
Many causes have been suggested, including diseases, parasites, reduction in the range of flowers growing wild in the countryside, pesticides, or a combination of them all.
The neonicotinoids investigated in the two Science papers are used on crops such as cereals, oilseed rape and sunflowers.
Often the chemical is applied to seeds before planting. As the plant grows, the pesticide is contained in every part of it, deterring insect pests such as aphids.
But it also enters the pollen and nectar, which is how it can affect bees.
Dave Goulson from the UK's University of Stirling and colleagues studied the impact of the neonicotinoid imidacloprid on bumblebees.
They let bees from some colonies feed on pollen and sugar water containing levels of imidacloprid typically found in the wild, while others received a natural diet.
Then they placed the colonies out in the field.
After six weeks, colonies exposed to the pesticide were lighter than the others, suggesting that workers had brought back less food to the hive.
But the most dramatic effect was on queen production. The naturally-fed hives produced around 14 queens each - those exposed to the pesticide, just two.
"I wouldn't say this proves neonicotinoids are the sole cause of the problems bees face," said Dr Goulson, "but it does suggest they're likely to be one of the causes, and possibly a significant one.
"The use of these pesticides is so widespread that most bee colonies in areas of arable farming are likely to be exposed to them, so there is potential for them to be playing a significant role in suppression of bee populations on a pretty staggering scale."
The French research group investigated the impact of a different neonicotinoid, thiamethoxam, on the number of bees able to make it back to the colony after release.
Using tiny tags attached to the bees' backs, they showed that significantly fewer insects came back if they had previously been exposed to levels of thiamethoxam that they might encounter on farms.
Calculations showed the impairment was bad enough that the capacity of colonies survive could be severely compromised…”
Fossils Foot Bones Hint at Mystery Walker
|3:56:10 AM, Thursday, March 29, 2012|
"(BBC)Scientists have obtained a fascinating new insight into the evolution of humans and our ability to walk. It comes from the fossilised bones of a foot that were discovered in Ethiopia and dated to be 3.4 million years old.
The researchers say they do not have enough remains to identify the species of hominin, or human ancestor, from which the right foot came.
But they tell Nature journal that just the shape of the bones shows the creature could walk upright at times.
The fossil haul consists of eight elements from the forefoot - bones such as metatarsals and phalanges.
The specimens were pulled from clay sediments at Burtele in the central Afar region, about 520km north-east of the capital Addis Ababa.
It is a significant discovery because it demonstrates there was more than one pre-human species living in East Africa between three and four million years ago, each with its own method of moving around.
The other creature was the famous "Lucy" animal (Australopithecus afarensis), whose remains were first identified in the Afar in the 1970s.
Lucy's body was built for walking. Her big toe was aligned with the other four digits of the foot, and she had a human-like arch that allowed for very efficient locomotion.
The owner of the partial foot from Burtele was not afarensis; that can be said definitively.
The fossils indicate it had no arch and the big toe was opposed to the other digits, enabling the animal to grasp branches in a tree.
But the fact this creature could and would walk on the ground is evidenced by the nature of the bone joints. These were arranged such that the foot could push off, or toe-off - something only humans do as they walk, and something flat-footed apes cannot achieve.
"If you look at the lateral metatarsal head along with the proximal toe bone, the phalanx - that particular joint is really unique in hominids," explained team member Dr Bruce Latimer of Case Western Reserve University, US.
"You can see it's a very different kind of a joint, because when you toe-off and push forward in that last phase of walking, your toes are highly flexed. In order to achieve that, you have to change the base of the phalanx and the metatarsal head - you have to change both sides of the joint. And it's a highly characteristic type of change that we can pick out immediately," he told the BBC.
The scientists can only speculate as to identity of the Burtele species. Without skull and teeth elements, a formal classification is impossible.
The team says the animal's morphology is reminiscent in some respects to a 4.4-million-year-old creature known as Ardipithecus ramidus. Although, again, it is not ramidus.
"It may be a relic species that was lingering around until 3.4 or 3.3 million years ago, and which had its origins way back in Ardipithecus ramidus times," suggested team leader Dr Yohannes Haile-Selassie.
"But obviously we cannot put it into the Ardipithecus genus or call it a ramidus species because we do not have any craniodental elements associated with this foot.
"We've kept digging at the Burtele site; we have a few isolated teeth, but that's all," the Cleveland Museum of Natural History curator told BBC News.
It is, though, a remarkable thought that there were these two very distinct species effectively rubbing shoulders with each other 3.4 million years ago in what is now Ethiopia.
The landmark Lucy specimen unearthed in 1974 was found at Hadar, about 50km from Burtele. Other remains of afarensis have been discovered closer still.
Dr Isabelle De Groote is a palaeoanthropologist at London's Natural History Museum.
"I think this is really exciting," she said.
"We have so few foot remains, they so rarely preserve, that we tend to take great leaps through evolution where there are no specimens at all representing long periods of time," she commented.
"This new foot helps elucidate the process of how the bi-pedal foot evolved. We can see something of the sequence in how changes to bones occurred.""
NASA Probe Offers New View of Mercury: an Alien World Right in Our Back Yard
|12:34:22 AM, Wednesday, March 28, 2012|
“The overheated, underappreciated runt of the solar system is finally getting some attention.
Mostly ignored since a brief fly-by in the 1970s, Mercury, our solar system’s smallest, swiftest planet, received a longer house call last March: NASA’s $450 million Messenger probe, which achieved orbit, a tricky feat never before attempted.
Now, after poring over 100,000 images and reams of other Messenger data, space scientists have achieved consensus: Mercury is one weird world.
It is radically unlike the other rocky bodies of our solar system — Venus, Mars, Earth, the moon, and the moons of other planets. Its core is too big; its surface too scrunched. It looks shriveled, like a liposuction patient left with too much skin. It contains too much iron. Its internal structure — how the planet is built — is confounding. Its magnetic field is out of whack, asymmetrical. And its surface is strange, a jagged, ragged landscape of soaring escarpments, snaking faults, half-buried “ghost craters,” dead volcanos and mysterious pit-marked “hollows.”
“It’s been really spectacularly baffling,” said MIT’s Maria Zuber, of the Messenger data, which scientists reported on in two scientific articles and 57 presentations at the annual Lunar and Planetary Science Conference last week.
Mercury was long viewed as an inert lump, but Zuber and her colleagues now say it is still cooling and still shrinking, pushing up scarps — steep cliffs — that run for hundreds of miles. Not long ago (geologically speaking), volcanoes threw up showers of magma, which hardened into huge plains. There’s also evidence of mysterious explosions of interior gases that rocked the surface and left strange, pitted scars.
Massive interior forces have pushed and tilted huge stretches of the surface. Mercury’s biggest crater — the Caloris Basin, some 900 miles wide — has been so uplifted that much of its floor is taller than its rim. No other crater in the solar system looks like it.
“Everything is intriguing on the surface of Mercury,” said Nancy Chabot of the Applied Physics Laboratory at Johns Hopkins University, which built Messenger. “It has landforms that we’ve never seen on the rest of the terrestrial planets.”
Mercury might even experience Mercury-quakes. “I would bet some of those faults are still active,” said Messenger’s lead scientist, Sean Solomon of the Carnegie Institution for Science.
And despite being the closest planet to the sun, it apparently has buried water ice surviving beneath permanent shadows thrown by craters. “We’re almost certain of it,” Solomon said.
‘Back to the drawing board’
Just how Mercury was formed is another baffler. It is heavy with iron and sulfur — much more than Earth contains. But all of the rocky inner planets coalesced from the same disk of material. So why is Mercury so strange? “It’s like children in the same family,” Zuber said. “Same genes, same environment, yet they turn out so different.”
Some theorists say a giant space rock smashed into Mercury early on, ripping off a thick outer layer. But Messenger data throw that theory into chaos. Sulfur and other “volatiles” survive on the surface; a huge collision should have wiped them clear…”
African Women And A Western Woman Compare Breasts
|3:37:52 PM, Monday, March 26, 2012|
This is a kind of lovely example of how different cultures are, and yet how similar individuals are no matter where they're from.
-- Follow the link for the rest of the photos. =)
The Sonixx – You Don’t Like Me
|3:13:14 PM, Monday, March 26, 2012|
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