Alien Life More Likely on 'Dune' Planets, Study Suggests
|1:21:27 AM, Saturday, September 03, 2011|
"Desert planets like the one depicted in the science fiction classic "Dune" might be the most common type of habitable planet in the galaxy, rather than watery worlds such as Earth, a new study suggests.
And that's not the only surprising result.
The study also hints that scorching-hot Venus, where surface temperatures average 860 degrees Fahrenheit (460 degrees Celsius), might have been a habitable desert world as recently as 1 billion years ago.
Follow the water?
Nearly everywhere there is water on Earth, there is life. The search for life elsewhere in the universe has been guided by this fact, largely focusing on "aqua planets" with a lot of liquid water on their surfaces.
These worlds could be terrestrial planets largely covered with oceans, such as Earth, or theoretical "ocean planets" completely covered by a layer of water hundreds of miles deep, somewhat like thawed versions of Jupiter's icy moon Ganymede.
To be habitable, aqua planets must orbit their stars in a so-called "Goldilocks zone" where they are neither too hot nor too cold. If they are too far from the sun, they freeze. If they are too close, steam builds up in their atmospheres, trapping heat that vaporizes still more water, leading to a runaway greenhouse effect that boils all the oceans off the planet, as apparently happened on Venus.
Eventually, such planets get so hot, they force water vapor high enough into the atmosphere that it gets split into hydrogen and oxygen by ultraviolet light. The hydrogen then escapes into space, the oxygen likely reacts with the molten surface and gets incorporated into the mantle, and the planet's atmosphere loses all its water over time.
Instead of aqua planets with abundant water on their surfaces, researchers investigated what "land planets" might be like, ones with no oceans and vast dry deserts, but perhaps oases here and there. The planet Arrakis depicted in the science fiction classic "Dune" is one exceptionally well-developed example of a habitable land planet, said planetologist Kevin Zahnle at NASA's Ames Research Center in Mountain View, Calif..."
Why Does Muammar Qaddafi Own a Mansion in New Jersey?
|1:13:32 AM, Saturday, September 03, 2011|
"As General Muammar Qaddafi continues to evade the Libyan rebels who chased him out of Tripoli last week, there has been some tongue-in-cheek speculation about the possibility of him fleeing all the way to his five-acre estate in—wait for it—Englewood, New Jersey.
Almost thirty years ago, in 1982, the Libyan government paid a million bucks for this three-story, 10,000 square foot, 25-bedroom mansion, which they inexplicably named “Thunder Rock,” on Palisade Avenue in Englewood, a suburb in Bergen County. It’s a bizarre choice of neighborhood for a government that has made a habit of bankrolling terrorists and talking about how much they hate Israel, considering it’s right smack in the middle of a sizeable Orthodox Jewish community. In fact, Thunder Rock is directly next door to the largest yeshiva in town, and just a short walk from the home of one Rabbi Shmuley Boteach, who, if in case you missed that episode of Oprah, is an outspoken leader in the American Jewish community and a former spiritual mentor to Michael Jackson.
Thunder Rock was originally purchased as a summer retreat for the Libyan ambassador to the U.S. and his or her family, but it was never really used, and in the last decade or so, the now multi-million dollar pad had mostly wallowed in obscurity, with a few notable exceptions. In 1985, it was the subject of a prolonged legal battle, which ended with the court decision that the Libyan government would not have to pay property taxes on the place.
It was a decision that rankled New Jerseyans, especially when, twenty-four years later, in 2009, Qaddafi proposed setting up his air-conditioned Bedouin tent—he always travels with one—on the mansion’s front lawn. The little camping trip would, the Englewood mayor predicted, cost residents an estimated $20,000 per day in police presence and garbage removal..."
Oldest Fossils On Earth Discovered
|12:07:55 AM, Saturday, September 03, 2011|
"Earth's oldest fossils have been found in Australia by a team from the University of Western Australia and Oxford University. The microscopic fossils show convincing evidence for cells and bacteria living in an oxygen-free world over 3.4 billion years ago.
The team, led by Dr David Wacey of the University of Western Australia and including Professor Martin Brasier of Oxford University, report the finding in the journal Nature Geoscience.
'At last we have good solid evidence for life over 3.4 billion years ago. It confirms there were bacteria at this time, living without oxygen,' says Professor Brasier of the Department of Earth Sciences at Oxford.
Earth was still a hot, violent place at this time, with volcanic activity dominating the early Earth. The sky was cloudy and grey, keeping the heat in despite the sun being weaker than today. The water temperature of the oceans was much higher at 40-50 degrees -- the temperature of a hot bath -- and circulating currents were very strong. Any land masses were small, or about the size of Caribbean islands, and the tidal range was huge.
Significantly, there was very little oxygen present as there were no plants or algae yet to photosynthesise and produce oxygen. The new evidence points to early life being sulfur-based, living off and metabolizing compounds containing sulfur rather than oxygen for energy and growth.
'Such bacteria are still common today. sulfur bacteria are found in smelly ditches, soil, hot springs, hydrothermal vents -- anywhere where there's little free oxygen and they can live off organic matter,' explains Professor Brasier..."
Astronomy Picture of the Day: Stars and Dust Across Corona Australis
|12:01:15 AM, Friday, September 02, 2011|
-- "Cosmic dust clouds sprawl across a rich field of stars in this sweeping telescopic vista near the northern boundary of Corona Australis, the Southern Crown. Probably less than 500 light-years away and effectively blocking light from more distant, background stars in the Milky Way, the densest part of the dust cloud is about 8 light-years long. At its tip (upper right) is a group of lovely reflection nebulae cataloged as NGC 6726, 6727, 6729, and IC 4812. A characteristic blue color is produced as light from hot stars is reflected by the cosmic dust. The smaller yellowish nebula (NGC 6729) surrounds young variable star R Coronae Australis. Magnificent globular star cluster NGC 6723 is toward the upper right corner of the view. While NGC 6723 appears to be part of the group, it actually lies nearly 30,000 light-years away, far beyond the Corona Australis dust clouds. "
Bored UCLA Student Joins Libyan Rebels
|11:15:33 PM, Thursday, September 01, 2011|
"Bummed out by the end of summer vacation? Want to take the awesomest road trip evar? Not really bothered by the idea of conflict tourism or turning someone else’s struggle for freedom into your bar-stool anecdote?
Dude: you need to join the Libyan revolution!
Bradley Hope, a reporter covering Libya’s uprising, writes in Abu Dhabi newspaper The National that he recently made a curious discovery near An Nawfaliyah: Chris Jeon, a 21-year old University of California–Los Angeles math student. That’s Jeon in the picture above, very unsafely resting his rifle on the ground with the barrel pointed up while his new buddies crowd around. Spoiler: He doesn’t have any military experience.
Why’d he make the long trek from L.A. to L-iby-A? “It is the end of my summer vacation, so I thought it would be cool to join the rebels,” Jeon told Hope. “This is one of the only real revolutions..."
Reflecting The Old World by Nelleke Pieters
|10:52:14 PM, Thursday, September 01, 2011|
Pillow Fight! How Start A Random Pillow Fight With A Stranger
|10:48:43 PM, Thursday, September 01, 2011|
-- The first rule of Pillow Fight Club is, you do not talk about Pillow Fight Club.
You’re gonna start a pillow fight — and you’re gonna lose.
First Lizard Genome Sequenced
|10:39:12 PM, Thursday, September 01, 2011|
"The green anole lizard is an agile and active creature, and so are elements of its genome. This genomic agility and other new clues have emerged from the full sequencing of the lizard’s genome and may offer insights into how the genomes of humans, mammals, and their reptilian counterparts have evolved since mammals and reptiles parted ways 320 million years ago.
Researchers in Harvard’s Department of Organismic and Evolutionary Biology (OEB) and the Broad Institute of Harvard and MIT who completed this sequencing project reported their findings online today in the journal Nature.
The green anole lizard (Anolis carolinensis) — a native of the Southeastern United States — is the first nonbird species of reptile to have its genome sequenced and assembled. Harvard and Massachusetts Institute of Technology researchers at the Broad have assembled and analyzed more than 20 mammalian genomes — including those of some of our closest relatives — but the genetic landscape of reptiles remains relatively unexplored.
“Sometimes you need to be at a certain distance in order to learn about how the human genome evolved,” said Jessica Alföldi, a Broad research scientists who is co-first author of the paper and a member of the Broad’s vertebrate genome biology group. “You have to look out further than you were looking previously.”
Lizards are more closely related to birds — which are also reptiles — than to any of the other organisms whose genomes have been sequenced in full. Like mammals, birds and lizards are amniotes, meaning that they are not restricted to laying eggs in water. “People have been sequencing animals from different parts of the vertebrate tree, but lizards had not been previously sampled,” said Kerstin Lindblad-Toh, scientific director of vertebrate genome biology at the Broad and senior author of the Nature paper. “This was an important branch to look at.”
Four hundred species of anole lizards have fanned out across the islands of the Caribbean, North America, Central America, and South America, making them an appealing model for studying evolution. Although much is known about their biology and behavior, genomic information may be a critical missing piece for understanding how the lizards have become so diverse..."
Laser Advances in Nuclear Fuel Stir Terror Fear
|10:33:29 PM, Thursday, September 01, 2011|
"Scientists have long sought easier ways to make the costly material known as enriched uranium — the fuel of nuclear reactors and bombs, now produced only in giant industrial plants.
One idea, a half-century old, has been to do it with nothing more substantial than lasers and their rays of concentrated light. This futuristic approach has always proved too expensive and difficult for anything but laboratory experimentation.
In a little-known effort, General Electric has successfully tested laser enrichment for two years and is seeking federal permission to build a $1 billion plant that would make reactor fuel by the ton.
That might be good news for the nuclear industry. But critics fear that if the work succeeds and the secret gets out, rogue states and terrorists could make bomb fuel in much smaller plants that are difficult to detect.
Iran has already succeeded with laser enrichment in the lab, and nuclear experts worry that G.E.’s accomplishment might inspire Tehran to build a plant easily hidden from the world’s eyes.
Backers of the laser plan call those fears unwarranted and praise the technology as a windfall for a world increasingly leery of fossil fuels that produce greenhouse gases.
But critics want a detailed risk assessment. Recently, they petitioned Washington for a formal evaluation of whether the laser initiative could backfire and speed the global spread of nuclear arms..."
Earliest Signs of Advanced Tools Found
|8:58:29 PM, Wednesday, August 31, 2011|
"One hallmark of Homo erectus, a forerunner of modern humans, was his stone tools, an advanced technology reflecting a good deal of forethought and dexterity. Up to now, however, scientists have been unable to pin a firm date on the earliest known evidence of his stone tool-making.
A new geological study, being reported Thursday in the journal Nature, showed that tools from a site near Lake Turkana in Kenya were made about 1.76 million years ago, the earliest of their ilk found so far. Previous dates were estimates ranging from 1.4 million to 1.6 million years ago.
Although no erectus fossils were found with the Turkana tools, a skull of that species was excavated last year in the same sediment level across the lake. This suggests that Homo erectus was responsible for these particular tools, which were made with what scientists refer to as Acheulean technology. The term connotes the type of oval and pear-shaped hand axes and other implements that were a specialty of early humans.
American researchers at the Lamont-Doherty Earth Observatory, part of Columbia University, established the age of the Turkana tools by dating the surrounding mudstone with a paleomagnetic technique. When layers of silt and clay hardened into stone, this preserved the orientation of Earth’s magnetic field at the time, and an analysis of the periodic polarity reversals and other records yielded the age of the site known as Kokiselei.
“I was taken aback when I realized that the geological data indicated it was the oldest Acheulean site in the world,” said the lead author of the report, Christopher J. Lepre, a researcher at Lamont-Doherty who also teaches geology at Rutgers University..."
Humpback Whale Shows AMAZING Appreciation After Being Freed From Nets
|8:50:10 PM, Wednesday, August 31, 2011|
Saudi Arabia Discovers 9,000 Year-Old Civilization
|2:24:47 PM, Wednesday, August 31, 2011|
"(Reuters) - Saudi Arabia is excavating a new archaeological site that will show horses were domesticated 9,000 years ago in the Arabian peninsula, the country's antiquities expert said on Wednesday.
The discovery of the civilization, named al-Maqar after the site's location, will challenge the theory that the domestication of animals took place 5,500 years ago in Central Asia, said Ali al-Ghabban, Vice-President of Antiquities and Museums at the Saudi Commission for Tourism & Antiquities.
"This discovery will change our knowledge concerning the domestication of horses and the evolution of culture in the late Neolithic period," Ghabban told a news conference in the Red Sea port of Jeddah.
"The Maqar Civilization is a very advanced civilization of the Neolithic period. This site shows us clearly, the roots of the domestication of horses 9,000 years ago."
The site also includes remains of mummified skeletons, arrowheads, scrapers, grain grinders, tools for spinning and weaving, and other tools that are evidence of a civilization that is skilled in handicrafts.
Saudi Arabia, the world's largest oil exporter, is trying to diversify its economy away from oil and hopes to increase its tourism..."
The Star That Should Not Exist
|2:12:04 PM, Wednesday, August 31, 2011|
"A team of European astronomers has used ESO’s Very Large Telescope (VLT) to track down a star in the Milky Way that many thought was impossible. They discovered that this star is composed almost entirely of hydrogen and helium, with only remarkably small amounts of other chemical elements in it. This intriguing composition places it in the “forbidden zone” of a widely accepted theory of star formation, meaning that it should never have come into existence in the first place. The results will appear in the 1 September 2011 issue of the journal Nature.
A faint star in the constellation of Leo (The Lion), called SDSS J102915+172927 , has been found to have the lowest amount of elements heavier than helium (what astronomers call “metals”) of all stars yet studied. It has a mass smaller than that of the Sun and is probably more than 13 billion years old.
“A widely accepted theory predicts that stars like this, with low mass and extremely low quantities of metals, shouldn’t exist because the clouds of material from which they formed could never have condensed,”  said Elisabetta Caffau (Zentrum für Astronomie der Universität Heidelberg, Germany and Observatoire de Paris, France), lead author of the paper. “It was surprising to find, for the first time, a star in this ‘forbidden zone’, and it means we may have to revisit some of the star formation models.”
The team analysed the properties of the star using the X-shooter and UVES instruments on the VLT . This allowed them to measure how abundant the various chemical elements were in the star. They found that the proportion of metals in SDSS J102915+172927 is more than 20 000 times smaller than that of the Sun .
“The star is faint, and so metal-poor that we could only detect the signature of one element heavier than helium — calcium — in our first observations,” said Piercarlo Bonifacio (Observatoire de Paris, France), who supervised the project. “We had to ask for additional telescope time from ESO’s Director General to study the star’s light in even more detail, and with a long exposure time, to try to find other metals.”
Cosmologists believe that the lightest chemical elements — hydrogen and helium — were created shortly after the Big Bang, together with some lithium , while almost all other elements were formed later in stars. Supernova explosions spread the stellar material into the interstellar medium, making it richer in metals. New stars form from this enriched medium so they have higher amounts of metals in their composition than the older stars. Therefore, the proportion of metals in a star tells us how old it is..."
Why Math Works: Is Math Invented Or Discovered?
|2:00:54 PM, Wednesday, August 31, 2011|
"Most of us take it for granted that math works—that scientists can devise formulas to describe subatomic events or that engineers can calculate paths for spacecraft. We accept the view, initially espoused by Galileo, that mathematics is the language of science and expect that its grammar explains experimental results and even predicts novel phenomena. The power of mathematics, though, is nothing short of astonishing. Consider, for example, Scottish physicist James Clerk Maxwell’s famed equations: not only do these four expressions summarize all that was known of electromagnetism in the 1860s, they also anticipated the existence of radio waves two decades before German physicist Heinrich Hertz detected them. Very few languages are as effective, able to articulate volumes’ worth of material so succinctly and with such precision. Albert Einstein pondered, “How is it possible that mathematics, a product of human thought that is independent of experience, fits so excellently the objects of physical reality?”
As a working theoretical astrophysicist, I encounter the seemingly “unreasonable effectiveness of mathematics,” as Nobel laureate physicist Eugene Wigner called it in 1960, in every step of my job. Whether I am struggling to understand which progenitor systems produce the stellar explosions known as type Ia supernovae or calculating the fate of Earth when our sun ultimately becomes a red giant, the tools I use and the models I develop are mathematical. The uncanny way that math captures the natural world has fascinated me throughout my career, and about 10 years ago I resolved to look into the issue more deeply..."
In Massive Tahitian Waves, The Most Incredible Day Of Surfing Ever?
|1:28:17 PM, Wednesday, August 31, 2011|
"Kelly Slater this week won a major surf competition in large waves at a notoriously treacherous venue in Tahiti. But the buzz around the Billabong Pro still is mostly about what transpired during an off day in the middle of the event, when more than a dozen tow surfers took over in gargantuan surf and participated in what some observers described as the most incredible and intense big-wave session ever recorded.
Waves at Teahupoo, which break over an extremely shallow reef, were peaking at 25-plus feet. The ASP World Tour had declared a "code red" situation because the swells were too large and breaking too swiftly too be safely caught by paddle power. Slater mentioned how they're more like tsunamis because of the force with which the fast-moving swells shove against the reef. "They reach a point where they don't get any taller. They just get thicker," he said.
Tow surfers enjoy the benefit of skiing onto building waves behind personal watercraft, then letting go of the rope and surfing on customized boards. Many expert tow surfers, who had arrived in anticipation of the giant swell, eagerly took to the lineup, although this was no carefree day of surfing..."
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