Sunday, June 15, 2008

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2008 June 15

Phoenix Digs for Clues on Mars
Credit: Phoenix Mission Team, NASA, JPL-Caltech, U. Arizona, Texas A&M University

Explanation: What's a good recipe for preparing Martian soil? Start by filling your robot's scoop a bit less than half way. Next, dump your Martian soil into one of your TEGA ovens, being sure to watch out for clumping. Then, slowly increase the temperature to over 1000 degrees Celsius over several days. Keep checking to see when your soil becomes vaporized. Finally, your Martian soil is not ready for eating, but rather sniffing The above technique is being used by the Phoenix Lander that arrived on Mars three weeks ago. Data from the first batch of baked soil should be available in a few days. Pictured above, a circular array of the Phoenix Lander's solar panels are visible on the left, while a scoop partly filled with Martian soil is visible on the right. The robotic Phoenix Lander will spend much of the next three months digging, scooping, baking, sniffing, zapping, dissolving, and magnifying bits of Mars to help neighboring Earthlings learn more about the hydrologic and biologic possibilities of the sometimes mysterious red planet.

Original here

Are we aliens?

Are we aliens? This question has come up due to a new result from studying meteorites, and is getting a lot of web-chatter. I figure I’d better get on this sooner rather than later!

First, the science. Then the chatter. Finally, the caution flag. :-)

The Science:

A fragment of the Murchison meteoriteSome meteorites have been found to contain some relatively complicated organic compounds, including molecules that are components of amino acids, the building blocks of life. For example, the Murchison meteorite, which fell on Australia in 1969, has been found to contain purines and pyrimidines, which are crucial to a large number of biological molecules like DNA, RNA, and ATP (adenosine triphosophate, a chemical our cells use for fuel).

Now, you have to be careful. A meteorite might have had these molecules in it before it slammed into the Earth, or it may have absorbed them from the ground after impact. One way to tell the difference is to look at isotopes of the elements. An element like carbon usually has 6 protons and 6 neutrons in its nucleus, but an isotope is when the number of neutrons is different. Carbon 13, as an example, has 6 protons and 7 neutrons in the nucleus (the number of protons determines the chemical properties, so carbon 13 is still like carbon, though a tad heavier).

The ratio of isotopes in a sample can be different for objects in space versus on Earth. Various process can change the ratio, so that’s a good way to find out if these molecules are native to a meteorite, or if it was contaminated after it fell.

OK, that’s the primer. Now the good part: scientists studying the Murchison meteorite have determined that the purines and pyrimidines — specifically, uracil and xanthine — have a non-terrestrial origin. In other words, the molecules in this meteorite, so crucial for life, were actually formed in outer space and fell to Earth.

That is very, very cool.

So this means that the some of the basic building blocks of life formed out in space, and came to Earth via meteorites and, presumably, comets.

Note that "some of". That’s important. Because…

The Chatter:

This news is being picked up all over the blogosphere and news sites, of course. We’re aliens! lots of people are saying. I’m quite sure the panspermia folks are having nerdgasms over this news as well.

Well, I hate to throw some cold H2O on all this, but I’m gonna. Just a little, a few drops. I think this is big news, and extremely awesome, but I want to make sure people don’t take it farther than the evidence suggests.

The Caution Flag:

Let’s take a step back and see what this new finding really tells us. First of all, I have little reason to doubt the results — of course as a scientist I reserve some skepticism, but let’s assume the team was on the money and the results are accurate. (I don’t have access to the journal paper, sadly, but I’ll dig around and see if anyone else does) (I have the paper now; thanks to Preston Hart and Stan Gunn!).

So the Murchison meteorite has native chemicals in it that are the basis for life. Obviously, since they were found at all, that means they survived entry into our atmosphere and impact. This in turn means that in the distant past, when the Earth was bombarded by such rocks, these chemicals were scattered across the planet, where they could be incorporated into ever more complex molecules, which eventually became life. And, well, us.

Well, cool. And even, wow! It’s been hypothesized for years, decades, that the basis of organic chemistry may have fallen to Earth from space. And now we know that it’s true.

However, that does not mean that all of these chemicals came from space! Transport yourself back a few billion years. The Earth has just suffered a several hundred million year bombardment period, getting the crap pummeled out of it by impacts. But that finally ended, and the crust started to cool. The trickle of impacts that continued — some of which contained the organic compounds — fall to Earth. If they fall into a hostile environment, they’ll get destroyed, of course? But if the environment is not hostile to them, then it’s also possible these compounds could have formed right here, on Earth! It may be easier for them to form in space, where conditions may have been better, but that doesn’t preclude them forming here.

So it’s still possible that even though these compounds fell to Earth after the Earth settled down, it’s also possible the majority of such compounds formed right here, in situ. The original molecules are long, long gone, so we cannot test them for isotopes. There may yet be some way of determining if life actually formed from space compounds or from terrestrial ones, but right now I don’t think there is — I haven’t heard of one, at least.

So what these new results show is that life here might have formed from compounds that fell from space. It may even be likely. But it’s not rock-solid fact. As the scientists say on the abstract of their paper (emphasis mine):

These new results demonstrate that organic compounds, which are components of the genetic code in modern biochemistry, were already present in the early solar system and may have played a key role in life’s origin.

To be even more broad, and to stop any extrapolation here, this also does not mean that life itself formed in space and fell here. We’re only talking building blocks here, not viruses, RNA, DNA, or bacteria. Just chemicals.

There is a group of folks who claim that every unexplained molecule must have fallen from space. Panspermia is a cool idea, and may even be right — but the group at Cardiff (founded by Hoyle and Wickramasinghe) make outrageous claims about bacteria and viruses from space, with almost no real supporting evidence that I have seen.

So you have to be careful to not fall into a "God of the gaps" argument: because we can’t explain something now, that doesn’t mean it must be due to some supernatural (or extremely unlikely) cause. That’s a bad path to follow, because eventually someone will fill that gap with evidence, and then your supernatural cause gets squeezed out. For example, creationists say that the eye could not have evolved, therefore God did it. But now we understand pretty well how the eye evolved, and the creationist’s explanation looks silly. They found a gap in knowledge, proclaimed a supernatural explanation, and it turned out to be natural after all.

I put panspermia into that category for the moment. While there is some real science, and really interesting science, to pursue there, it’s not a panacea for all things biologica-ex-nihilo.

The Conclusion:

So here are the big points:

1) Researchers have found that some molecules which are the basis for life on Earth can have an extraterrestrial origin.

2) These molecules survived their impact with Earth.

3) These alien molecules may have been crucial to the development of life on Earth.

4) These needed building blocks of life may have also been formed right here on Earth, so we can’t fly off the handle.

5) Intact life from space — bacteria, viruses, and such — is still just an idea, with no credible supporting evidence.

But the really big point is that this is an amazing and wonderful discovery! It is entirely possible that life here — or at least the necessary components of it — began out there. This is one of those discoveries that makes you think, and sparks discussion, and also just happens to have some profound philosophical ramifications. I’m in favor of all three of those things!

So remember, when you go outside at night and look up, the sky is filled with far more than just the stars you see. Our future is up there, and our past. And, not incidentally, our present as well.

Original here

Stephen Hawking: ministers’ £80m error puts science at risk

Britain's most famous scientist, Stephen Hawking, has accused the government of making “disastrous” cuts to research funding that threaten the country’s international standing.

Hawking has released correspondence accusing ministers of putting science at risk through basic “bookkeeping errors” that have led to an £80m budget shortfall and warning that several university physics departments may be forced to close.

Separately, it has emerged that he has turned down the offer of a knighthood. “Professor Hawking does not like titles. In fact he dislikes the whole concept of them,” said a spokesman.

In the Queen’s birthday hon-ours this weekend, three respected but low-profile scientists are awarded knighthoods. The absence of a similar accolade for Hawking has long been one of British science’s minor puzzles.

Now Hawking has cleared up the mystery by revealing that he first turned down a title more than a decade ago and since then his resolve has only hardened.

His interventions on matters of public policy have been rare, but he has been angered by the cuts to physics funding that followed the government’s attempts to reor-ganise science. Last year ministers decided to merge the Particle Physics and Astronomy Research Council and the Council for the Central Laboratory of the Research Councils, which funded most of Britain’s physics research.

The merged body, the Science and Technology Facilities Council (STFC), was set up with an immediate shortfall of £80m because of mistakes in calculating the running costs of new laboratories. This immediately threatened the jobs of 600 physicists and the closure of facilities such as the Jodrell Bank radio telescope. It could also force Britain to pull out of global projects such as the Gemini telescopes in Hawaii.

British involvement in other major international projects – such as the new particle accelerator at Cern, the physics facility near Geneva – are not believed to be at risk. They do, however, further squeeze the cash available for spending in Britain.

An independent inquiry is under way into the crisis, but this week Ian Pearson, the science minister, is due to publish a report replying to a select committee that was highly critical of the government’s actions.

In his letter, Hawking said: “This bookkeeping error has disastrous implications. There is a possibility that very severe cuts will be made in the grants awarded to UK research groups.

“These grants are the lifeblood of our research effort; cutting them will hurt young researchers and cause enormous damage both to British science and to our international reputation. They could well lead to several physics departments closing.”

The threat to university physics departments has most angered Hawking and his fellow theoretical physicists. Neil Turok, professor of mathematical physics at Cambridge and a close colleague of Hawking, has already decided to quit Britain to become director of the Perimeter Institute in Ontario, Canada, this autumn.

“Experiments at the cutting edge of physics are designed to test theories, so theory is essential to their interpretation,” said Turok. “What the government is doing by cutting theory is consigning the UK to funding but not benefiting from these big experiments. It really is a dumb policy.”

Brian Cox, professor of particle physics at Manchester University, who is closely involved with the large hadron collider project at Cern, said he supported Hawking’s comments.

“The notion that scientists will make a more valuable contribution to the economic and social wellbeing of the world if their research is closely directed by politicians is the most astonishing piece of nonsense I have had the misfortune to come across in a long time,” Cox said.

Pearson has written to Hawking rejecting most such criticisms and has suggested the creation of the STFC has been a success. He said in a statement: “There was no deficit at the time of the merger; nor were there arithmetical errors. I can quite understand how those whose work is not funded may well question those who gave it a lower priority.”

For Hawking such battles may soon seem remote. He expects to spend more time abroad in future, partly in California and partly with Turok in Ontario.

Original here

New 'super-paper' is stronger than cast iron

Punching your way out of a paper bag could become a lot harder, thanks to the development of a new kind of paper that is stronger than cast iron.

The new paper could be used to reinforce conventional paper, produce extra-strong sticky tape or help create tough synthetic replacements for biological tissues, says Lars Berglund from the Swedish Royal Institute of Technology in Stockholm, Sweden.

Despite its great strength, Berglund's "nanopaper" is produced from a biological material found in conventional paper: cellulose. This long sugar molecule is a principal component of plant cell walls and is the most common organic compound on Earth.

Wood is typically about half cellulose, mixed with other structural compounds.

Support network

In plant cell walls individual cellulose molecules bind together to produce fibres around 20 nanometres in diameter, 5000 times thinner than a human hair. These fibres form tough networks that provide the cell walls with structural support.

"Cellulose nanofibres are the main reinforcement in all plant structures and are characterised by nanoscale dimensions, high strength and toughness," Berglund told New Scientist.

Cellulose is extracted from wood to make paper, is the basis of cellophane, and has also recently been used by materials scientists developing novel plastic materials. But they have used it only as a cheap filler material, ignoring its mechanical properties.

However, the mechanical processes used to pulp wood and process it into paper damage the individual cellulose fibres, greatly reducing their strength. So Berglund and colleagues have developed a gentler process that preserves the fibres' strength.

Tough as iron

The new method involves breaking down wood pulp with enzymes and then fragmenting it using a mechanical beater. The shear forces produced cause the cellulose to gently disintegrate into its component fibres.

The end result is undamaged cellulose fibres suspended in water. When the water is drained away Berglund found that the fibres join together into networks held by hydrogen bonds, forming flat sheets of "nanopaper".

Mechanical testing shows it has a tensile strength of 214 megapascals, making it stronger than cast iron (130 MPa) and almost as strong as structural steel (250 MPa).

Normal paper has a tensile strength less than 1 MPa. The tests used strips 40 millimetres long by 5mm wide and about 50 micrometres thick.

Dissipating stress

The secret to the nanopaper's performance is not only the strength of the undamaged cellulose fibres, but also they way they are arranged into networks. Although strongly bound together, they are still able to slip and slide over each other to dissipate strains and stresses.

The individual cellulose fibres are also much smaller than in conventional paper. "A regular paper network has fibres 30 micrometres in diameter, here we are at a scale three orders of magnitude smaller," says Berglund. "The material [has] very small defects compared with a conventional paper network."

"This [work] shows quite clearly the potential for cellulose nanofibres to provide a basis for reinforcement," says Stephen Eichhorn, a polymer scientist at the University of Manchester, UK.

Journal Reference: Biomacromolecules (DOI: 10.1021/bm800038n)

Original here

Wealth Of Genomic Hotspots Discovered In Embryonic Stem Cells

Singapore scientists at the Genome Institute of Singapore (GIS) and the National University of Singapore (NUS) have unveil an atlas that showing the location of "genomic hotspots" of essential protein "switches" (transcription factors) that are critical for maintaining the embryonic stem (ES) cell state.

Using advanced high throughput sequencing technology, the scientists discovered over 3,000 hotspots. These findings could improve understanding of the unique properties of stem cells that enable them to maintain their intriguing ability to grow and differentiate to virtually any cell type.

"This is the first time such a large scale study has been conducted in Singapore and obtaining such groundbreaking results has caused much excitement," said Wei Chia Lin, Ph.D., Senior Group Leader at GIS. "This blueprint that we obtained is like a treasure map, pointing us to specific sites where we can further study how these switches interact within the cell. Hopefully, this will eventually allow us unlock the secrets of stem cells."

Ng Huck Hui, Ph.D., also a Senior Group Leader at GIS, added, "we think that these 'stemness' hotspots are the most critical points in the genetic blueprint of ES cells. By targeting these hotspots, we may be able to reconnect the wiring in non-stem cells and jump-start the stem cell program in them. This can potentially create an inexhaustible source of clinically useful cells for regenerative medicine or cell based therapies in the future." The team has already started work to investigate further into this area of research.

"Using cutting edge sequencing technology, scientists from the GIS and NUS have identified hotspots in embryonic stem cells," said Prof. Lee Eng Hin, Executive Director of A*STAR's Biomedical Research Council. "These are important hubs of the genome of embryonic stem cells. This piece of work illustrates how scientists from different disciplines and across institutions can come together to define fundamental features of these intriguing cells."

"In this new paper in Cell, the team at the GIS continues their remarkable progress in defining the precise DNA sequences to which an important group of 13 transcriptional factors bind in mouse embryonic stem cells," said Alan Colman, Ph.D., Executive Director of Singapore's Stem Cell Consortium. "This particular group of factors is responsible for maintaining the self renewal and pluripotency of the embryonic stem cells. The team shows that many of the factors which bind to the same gene regions ('hotspots') and their work provide a working model of the transcriptional networks at play within the cells, and how these intracellular networks are linked to events that can be influenced by external stimuli."

The researchers performed genome-wide mapping of the in vivo binding sites for 13 sequence-specific transcription factors in ES cells. These transcription factors play different roles in self-renewal, pluripotency, reprogramming and chromatin insulation. This study uncovers two major modes of binding that give rise to transcription factor co- localization hotspots. The Nanog/Oct4/Sox2 centric hotspots are commonly co-bound by Smad1 and STAT3 and they represent points of integration for the intrinsic and external signaling pathways. The combinatorial wiring of transcription factors is important in deciphering the code behind gene expression program in ES cells.

The work done by the GIS team is a follow up on a series of ongoing research ( "The Oct4 and Nanog transcription network that regulates pluripotency in mouse embroynic stem cells," Nature Genetics 38:431-440, 2006) into understanding and mapping the transcriptional networks of master genes in ES and somatic cells.

Original here

Titanic discoverer Robert Ballard called to find lost sarcophagus

Franck Goddio discovered artefacts submerged in Alexandria and is also favoured in the search for the Beatrice

It has been a source of enduring fascination for archaeologists and amateur Egyptologists everywhere: what exactly happened to the sarcophagus of Menkaure, one of Egypt's greatest Pharaohs? Now, more than 170 years after it was found and lost, the mystery could be solved.

Built from polished blue basalt to transport the king's earthly remains to the next world, the elaborately decorated vessel lay hidden inside the third-largest of Giza's renowned Pyramids for more than 4,000 years. In 1837 the British colonel Richard William Howard Vyse blasted his way into Menkaure's sepulchral chamber using gunpowder and discovered the stone casket.

The mummy was missing by that time — ancient Arabic graffiti indicated that the colonel was not the first to find the chamber — and he realised that his discovery could open the way for a new generation of grave robbers. “As the sarcophagus would have been destroyed had it remained in the Pyramid,” he noted in his diaries, “I resolved to send it to the British Museum.”

In a twist worthy of an Indiana Jones film, the sarcophagus was lost again the following year before it could reach British shores. The merchant ship Beatrice, which was carrying it and other antiquities found by the archaeologist, sank while sailing from Malta to Gibraltar — reportedly off the coast of Spain, near Alicante.

Now the Egyptian Government wants to recover it with the aid of underwater robots. Zahi Hawass, who heads Egypt's Supreme Council for Antiquities, told Spanish journalists that he was seeking financing from the National Geographic Society for the search.

To locate the Beatrice he has lined up the services of Robert Ballard, who found the Titanic using high-tech submersibles. The Egyptians have also privately suggested Franck Goddio, the French marine archaeologist who has discovered hundreds of artefacts from submerged parts of Alexandria.

“I will seek a formula for co-operation with the Spanish Government and we will agree to return the sarcophagus to Egypt,” Dr Hawass said. Experts say that finding the ship will not be easy. In his account of the expedition Colonel Vyse noted that the Beatrice “was supposed to have been lost off Carthagena . . . as some parts of the wreck were picked up near the former port”. Other accounts say that the crew swam safely to shore, suggesting that the Beatrice lies in shallow water. Still others merely state that it went missing somewhere between Malta and Gibraltar — an impossibly large area to search.

“It's going to be very challenging to find something of that sort,” said John Baines, Professor of Egyptology at Oxford University. “Looking for something in the open Atlantic, which is nearly what this amounts to, strikes me as being a hopeless case.”

Dr Hawass is undeterred. “We have all the information from the time the ship sank, from Spanish newspapers and other sources,” he said. The Egyptian Ambassador in Madrid met Spanish officials this month to seek their co-operation in the project.

However, Spain is locked in a legal battle over a sunken treasure worth an estimated $500million (£256million) with the company that found and recovered it, the US-based Odyssey Marine Exploration. Spain is arguing that Odyssey looted one of its naval ships, Nuestra Señora de las Mercedes, which was sunk by the British fleet off the coast of Portugal in 1804, laden with gold and silver coins.

Some believe that Menkaure's sarcophagus being on a British vessel could complicate Spain's legal argument at a crucial moment. There is also the question of who would get the spoils if they were to be raised from the deep.

Original here

Roadside crater should have made more of an impact

HOW could evidence of a major asteroid impact have been missed when it was in plain sight all along? The telltale signs of a huge impact site were sitting alongside a busy road 8 kilometres north-east of Santa Fe, New Mexico.

Unusual cracks radiating from the tips of cone-shaped structures in rocks along the Santa Fe National Forest Scenic Byway were first spotted by independent geologist Tim McElvain. He called in experts, who identified the projections as shatter cones, distinctive structures that form when shock waves from a high-speed impact fracture the underlying rock.

The shatter cones are the biggest ever found, says Christian Koeberl at the University of Vienna in Austria. "To see 2-metre-high shatter cones on the side of the road took my breath away," he told New Scientist. "Who knows how many hundreds of thousands of people had driven by there without recognising them."

Koeberl, McElvain and colleagues went on to find additional shatter cones and other evidence of an impact over an area of 5 square kilometres, though the impact crater itself has long been obliterated by weathering and tectonic activity. They estimate the total area affected by the impact was 6 to 13 kilometres across, and that the asteroid responsible struck between 300 million and 1.2 billion years ago (Earth and Planetary Science Letters, DOI: 10.1016/j.epsl.2008.03.033)

he discovery suggests that many undiscovered impact sites are "still hiding right next to us", says Koeberl.

Comets and Asteroids - Learn more about the threat to human civilisation in our special report.

Nuclear Reactor Applications Rising

The Nuclear Regulatory Commission has received applications to build 15 new reactors in eight states. (AP / CBS)

(AP) The nation's nuclear energy industry, all but stagnant for three decades, is quietly building toward a resurgence with more than two dozen new reactors on the drawing board in 15 states.

The Nuclear Regulatory Commission has received applications to build 15 new reactors in eight states. Later this year, plants in seven other states plan to seek permits for a dozen more reactors.

The first could be built and operating by 2016.

While 104 commercial nuclear reactors remain in operation in the U.S., the NRC has not approved a construction license for a new reactor since 1978.

The nuclear revival is far from a done deal, however. Companies still must arrange financing, and will need federal loan guarantees and states' approval to hike rates to pay for construction if those loans are to be affordable.

The current push is being driven by soaring demand for electricity nationwide - about 25 percent more electric-generating capacity will be needed by 2030, according to industry experts. And utility companies say environmental and regulatory hurdles have stalled their efforts to build more coal-fired plants.

Economic incentives included in a 2005 energy bill passed by Congress are another factor, encouraging utilities to build new, advanced nuclear reactors that produce no greenhouse gases but cost billions to build.

"We're talking about a trillion-dollar investment in the nation's power infrastructure," said Steve Kerekes, a spokesman for the Nuclear Energy Institute, the industry's policy organization. "That's a very substantial undertaking in providing the electricity that we all depend on.

"We have to have nuclear power as part of that," he said. "We need renewables, but by themselves, that's not going to get us where we need to be."

But critics say solar, wind and other "greener" electricity-producing alternatives can play a bigger role, and that nuclear reactors are expensive and dangerous. Some residents near the proposed sites have protested, saying nuclear plants could become terrorist targets. Opponents also are concerned that while the updated reactors called for in the plans are used in Europe, they are untried in the U.S.

And in arid states such as Texas, where two companies are looking to build new reactors, there are concerns about the vast amounts of water such plants require. Most of the new plants would be built in the South, which has faced severe drought recently.

"Investing in a very expensive nuclear plant with technology that's never been used in this country is a risky and costly option," said Cyrus Reed, conservation director of the Sierra Club's Lone Star Chapter. "And there's no power source that uses more water, which is especially a problem in parts of Texas."

The last time the NRC approved a construction license for a nuclear reactor was in 1978 near Raleigh, N.C.; it started operating in 1987. The last reactor to go online in the U.S. was in 1996 - Watts Bar near Spring City, Tenn. - although its construction license was approved in 1973.

Dozens of permits were issued in the 1960s and '70s and nuclear reactors were built in the '70s and '80s, although some projects were scrapped because of high costs and new regulations, said Sam Walker, an NRC historian.

In 1979, an accident at the Three Mile Island nuclear power plant near Middletown, Penn., caused radioactive materials to be released. It was the most serious commercial nuclear plant disaster in the nation's history.

Although no one died, the NRC didn't issue licenses for a year and a half and the disaster prompted significant changes to safety, regulations and oversight, Walker said.

Since then, existing nuclear reactors have increased output by 25 percent, Kerekes said. But many are reaching their limits and some must eventually be decommissioned due to age.

The NRC received its first application in about 30 years in November, when Houston-based NRG Texas applied for a license to build two reactors at its South Texas Project near Bay City.

Dallas-based Luminant Power is expected to apply in September to build two reactors at its Comanche Peak plant in Glen Rose, about 50 miles south of Fort Worth. Luminant spokesman Tom Kleckner said the reactors are used in Japan, based on proven technology and have a good operating record.

Utilities looking to build new nuclear plants may have to wait in line for the huge steel containers that house the reactors. Most of the vessels - about the size of a 6-story building - are supplied by a single Japanese company.

They will also face the still-unresolved issue of long-term nuclear waste disposal.

The Bush administration is trying to get approval for a national 77,000-ton nuclear waste dump at Yucca Mountain outside Las Vegas. Federal law requires the government to take spent reactor fuel piling up at commercial power plants and defense sites.

But Nevada's attorney general has recently challenged that plan.

"We feel it's very important to go ahead with the project because we need to stop greenhouse gas emissions," said David Knox, an NRG Texas spokesman. "We're confident the government will meet its obligation."

Original here

Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2008 June 14

M51 Hubble Remix
Credit: S. Beckwith (STScI), Hubble Heritage Team, (STScI/AURA), ESA, NASA
Additional Processing: Robert Gendler

Explanation: The 51st entry in Charles Messier's famous catalog is perhaps the original spiral nebula - a large galaxy with a well defined spiral structure also cataloged as NGC 5194. Over 60,000 light-years across, M51's spiral arms and dust lanes clearly sweep in front of its companion galaxy (right), NGC 5195. Image data from the Hubble's Advanced Camera for Surveys has been reprocessed to produce this alternative portrait of the well-known interacting galaxy pair. The processing has further sharpened details and enhanced color and contrast in otherwise faint areas, bringing out dust lanes and extended streams that cross the small companion, along with features in the surroundings and core of M51 itself. The pair are about 31 million light-years distant. Not far on the sky from the handle of the Big Dipper, they officially lie within the boundaries of the small constellation Canes Venatici.

Original here

NASA: Missing clip no threat to re-entry

By MARCIA DUNN, AP Aerospace Writer

CAPE CANAVERAL, Fla. - A metal clip broke off Discovery's rudder and only four hours passed before the seven space shuttle astronauts got the good news: The missing part poses no danger for Saturday's re-entry and landing.

Ever since the Columbia tragedy five years ago, any shuttle part seen floating away in orbit gets NASA's attention — fast.

Mission Control reassured commander Mark Kelly and his crew on Friday that their spaceship was safe for coming home, and that the missing clip would not jeopardize anything. Good weather is expected for Saturday's landing in Florida.

A protrusion in the same area at the tail, reported by the astronauts around the same time, also was found to be harmless. The rudder's position made the so-called bump look strange when, in fact, that piece of thermal barrier was exactly how it looked at liftoff, Mission Control said.

During a pair of broadcast interviews on Friday the 13th, Kelly acknowledged that he and his crew were worried at first. The clip broke loose during a routine check of the flight systems needed for Saturday's descent.

Kelly said he was impressed at how quickly engineers were able to resolve the issues, and noted that the zoom-in photos of the fleeing clip, taken by one of his crewman, helped in the analysis.

LeRoy Cain, chairman of the mission management team, said without those pictures, it would have taken engineers longer to identify the lost piece and possibly could have delayed landing.

Space shuttles have returned to Earth in the past with clips missing from the rudder, which opens like a book to serve as a speed brake. The V-shaped spring tabs, just 2 1/2 inches by 1 inch, protect that area from the intense heat of liftoff by providing a seamless barrier down the back edge of the rudder, or tail, panels.

Engineers suspect this clip, or tab, came loose during the vibrations of launch on May 31, and it wasn't until the speed brake panels were opened for checkout Friday, that it floated away.

Following Columbia's destruction during re-entry in 2003, the Air Force went back through its radar images from the flight and found a small object in orbit with the space shuttle. Accident investigators concluded it almost certainly was a fragment of a heat panel from Columbia's gashed wing.

Flight director Richard Jones said his team "reacted with a very calm, levelheaded approach."

"We knew that we had to methodically work every single piece of data that we could get. After we had that in hand, it became clearer and clearer that we did not have an issue," Jones said.

Astronaut Garrett Reisman, meanwhile, returning after three months aboard the international space station, said he is "cautiously optimistic" that his adjustment to gravity won't be as bad as some have experienced, and that he may not suffer as many balance problems because he's short.

"My sensory organs are a little closer to my center of gravity, and my heart has a little less distance to pump to my brain," he said. "I've been waiting my whole life, and I think finally this being short is going to come in handy for once."

Reisman said he is looking forward to sleeping in his own bed and using his own toilet. He said in an earlier interview that his last month at the space station was difficult because of a broken toilet and preparations for Discovery's arrival.

The toilet was fixed after Discovery delivered a new pump along with the prime payload, a billion-dollar Japanese lab.

Reisman woke up on his 94th day in space to a song requested by his wife, Simone Francis, and beamed up by Mission Control: "Baby Won't You Please Come Home" by Louis Prima and Keely Smith.

"A special good morning to Simone, my favorite earthling," Reisman called down. "Get ready doll face, Discovery is coming home."


On the Net:


Original here

We may be extraterrestrials after all

London (UK) - Scientists from the Imperial College of London claim to have found evidence that life on our planet did not originate from Earth itself. For the first time, the scientists say, it is confirmed that an important component of early genetic material found in meteorite fragments is of extraterrestrial origin.

We had a lot of space and alien stories lately, with one particular interesting making even the Larry King show. But any of that material could be considered insignificant, if Zita Martins’ claims, a research associate at the Department of Earth Science and Engineering of the Imperial College, are in fact correct. According to the researcher, at least parts of the raw material that are believed to have been required to create the first molecules of DNA and RNA may be of extraterrestrial origin.

Martins and her colleagues said they discovered uracil and xanthine, which are precursors to the molecules that make up DNA and RNA and are known as nucleobases in rock fragments of the Murchison meteorite, which crashed in Australia in 1969. She explained that “early life may have adopted nucleobases from meteoritic fragments for use in genetic coding which enabled them to pass on their successful features to subsequent generations."

Apparently, the researchers were successful in proving that the molecules came from space and were not a result of contamination when the meteorite landed on Earth. What supports Martins claims is the fact that meteor showers are believed to have been common several billions of years ago on Earth: “Between 3.8 to 4.5 billion years ago large numbers of rocks similar to the Murchison meteorite rained down on Earth at the time when primitive life was forming,” the press release from the Imperial College reads. “The heavy bombardment would have dropped large amounts of meteorite material to the surface on planets like Earth and Mars.”

Mark Sephton, also of Imperial's Department of Earth Science and Engineering, believes this research is an important step in understanding how early life might have evolved. "Because meteorites represent left over materials from the formation of the solar system, the key components for life - including nucleobases - could be widespread in the cosmos,” he said. “As more and more of life's raw materials are discovered in objects from space, the possibility of life springing forth wherever the right chemistry is present becomes more likely."

The findings are published in the journal Earth and Planetary Science Letters.

Original here

Jurassic Park comes true: How scientists are bringing dinosaurs back to life with the help of the humble chicken

Deep inside the dusty university store room, three scientists struggle to lift a huge fossilised bone.

It is from the leg of a dinosaur.

For many years, this chunky specimen has languished cryptically on a shelf.

Interesting but useless — a forgotten relic of a lost age.

Now, with hammer and chisel poised, the academics from Montana State University in America gather round.

They are about to shatter this rare vestige of the past.

Why would they do such a thing?

Lost age: Scientists now believe it is possible to resurrect the dinosaur after the discovery of DNA relics in the wings and beaks of regular chickens

The answer is that they believe that this single fragment of a beast which stalked the earth untold millions of years ago could hold the key which will unlock the secrets of the dinosaurs.

Extraordinarily, they contend that it could lead to a real life Jurassic Park, where dinosaurs are once again unleashed on the world by scientists.

For just like in the hit Steven Spielberg movie, these men and women are intent on cracking the genetic code of the dinosaurs and opening the possibility of bringing them back to life.

Their remarkable quest will be revealed in a TV documentary, Dinosaurs: Return To Life, to be screened tomorrow.

Dinosaur - chickens contain DNA relics of original dinosaurs

Critter: In the Jurassic Park story dinosaurs were recreated using genetic code from mosquitos trapped in amber

It poses the question: will scientists ever be able to resurrect the dinosaur?

According to Jack Horner, professor of palaeontology at Montana State University, the answer is an unequivocal yes.

He says: ‘Of course we can bring them back to life. Their ancestral DNA is still present.

'The science is there. I don’t think there are any barriers, other than the philosophical.’

So just how have these scientists arrived at the point where they believe they might unleash the mysteries of a prehistoric lost world?

In order to understand their journey, we have to travel back a little less time — to 1992.

This was when Raul Cano, professor of microbiology at California Polytechnic State University, made the first attempt to extract DNA from insects almost as old as the dinosaurs that had been embedded in amber, a sticky tree sap which hardens into transparent orange stone.

Speculation about this possibility inspired the Jurassic Park story, in which an amber-trapped mosquito which sucked dinosaur blood unleashes its victims’ genetic code, allowing an obsessed billionaire to clone the species — with terrifying consequences.

In his real-life laboratory, Cano cracked the amber open with freezing cold liquid nitrogen, obtaining a sample of the insect inside.

Amazingly, he soon had a DNA sample from a 40 million-year-old bee.

Soon afterwards, academics at the American Museum of Natural History recovered DNA from an ancient termite.

It seemed that dinosaur DNA could soon be within reach of modern-day scientists.

But these early experiments ended in failure.

The scientists could not replicate their results, leading to the suspicion that the tiny recovered fragments were actually contaminants, perhaps from the researchers’ hair or clothing.

Fossil find: The discovery of the thigh bone of a Tyrannosaurus Rex in Montana, USA, revealed patterns only previously found in the bones of pregnant birds

The search for ancient DNA in amber was abandoned, and it seemed that the door to the past remained closed.

Since then however, researchers looking for prehistoric genetic fragments have managed to recover material from a 40,000-year-old mammoth, and from 45,000-year-old Neanderthal bones.

But still there were doubts that dinosaur DNA could have survived.

Then, in 2003, hopes were revived once again.

Horner, who acted as an advisor on the Jurassic Park films, made a remarkable discovery while his team were excavating a 68 million-year-old Tyrannosaurus Rex skeleton in Montana.

The site was so remote, the skeleton had to be removed by helicopter — the operation led to a huge thighbone splitting in two.

Horner gave a piece of the bone to one of his students, palaeontologist Mary Schweitzer.

Examining it, she noticed a strange structure inside the hard outer case.

It resembled a pattern found only in the bones of pregnant birds.

Experts say they have the ability to reach back to dinosaurs because their blueprints remains locked in modern-day birds

Puzzled, she asked her research assistant, Jennifer Wittmeyer, to dissolve the outer mineral layer.

Six hours later, there was a knock on the door.

‘Jennifer ran into the room saying, “You’re not going to believe this,”’ recalls Schweitzer.

‘When she picked up a small piece, it stretched and moved all over the place.

'So we knew we had something pretty unusual.’

The magnitude of the discovery was immediately apparent to the Montana University team — the material appeared to be well preserved flesh from a Tyrannosaurus Rex.

Horner says: ‘It’s unimaginable to find soft tissue. It was just assumed that everything had been fossilised.’

More extraordinary yet, was the next find in neighbouring parts of the dinosaur bone.

‘Out popped the blood vessels,’ says Schweitzer.

‘I said, “I don’t believe it, that’s not possible”. It was one of those goose bump moments.’

Horner and his team knew that blood vessels should not exist in fossilised bone.

Many scientists believed organic matter from a living thing could not survive more than 100,000 years — let alone 68 million years.

Next came the team’s attempt to salvage DNA from other bones kept in the university storerooms.

They put the samples they collected under a powerful microscope.

Magnified 4,000 times, tiny structures unlikely to be mineralised fossil material were apparent.

They seemed to be the microscopic cells that built dinosaur bones — called osteocytes.

So far, so good.

But Horner came to believe that his team needed to turn their work on its head if they were to unleash the dinosaur.

Amazing as the discovery of ‘living’ dinosaur tissue was, he feared that constructing a complete DNA map from it would be a never ending task.

So he embarked on a new strategy: retro-engineering a bird.

It is generally accepted by palaeontologists that birds are descended from a class of theropod dinosaurs called raptors.

‘If we want to see a dinosaur in our lifetime, we need to start with a bird and work backwards,’ says Horner.

‘As long as birds exist, we have the ability to reach back to dinosaurs.’

In the 1990s, scientists discovered dinosaurs in China buried in a fine ash.

They were preserved in remarkable detail and bird-like features, including claws and feathers, were recognisable.

Horner believes that a modern bird’s DNA contains a genetic memory that could be ‘switched on’ again, resurrecting long-dormant dinosaur traits.

To make such a creature, he would start with the genome (the whole hereditary information encoded in the DNA) of an emu.

‘Emus have all the features we need in order to make a Velociraptor-sized dinosaur,’ he says.

‘If I were to make a dinosaur, that is where I’d start.’

Far-fetched as this sounds, his work is supported by other leading academics.

Sean Carroll, a geneticist at the University of Wisconsin, says: ‘The inventory of genes in a bird would be very similar to the inventory of genes in a dinosaur.

‘It is differences in the decision-making that takes during development that make the difference between a chicken and a tyrannosaurus.’

Hans Larsson, a palaeontologist at McGill University in Canada, conducted an experiment in November 2007 into the evolution from dinosaurs’ long tails into birds’ short tails more than 150 million years ago.

Looking at a two-day-old chicken embryo, he made an unexpected discovery.

Expecting to see between four and eight vertebrae present in the developing spine, his microscope instead picked out 16 vertebrae — effectively a reptilian tail.

As the embryo developed, the ‘tail’ became shorter and shorter, until the young bird hatched with only five vertebrae.

Larsson says of the significance of the find: ‘For about 150 million years, this kind of a tail has never existed in birds.

'But they have always carried it deep inside their embryology.’

So, the blueprint for a dinosaur remained locked inside the modern-day bird.

Larsson decided to move from theory to reality.

He wanted to see if he could make a chicken grow a dinosaur’s tail, turning the clock back millions of years.

Manipulating the genetic make-up, he was able to extend the tail by a further three vertebrae.

Larsson had pinpointed a method for turning on dormant dinosaur genes.

If birds retained a dormant tail imprint, did they still retain a memory of dinosaur teeth?

In 2005, Matt Harris and John Fallon, developmental biologists at the University of Wisconsin, noticed something strange while researching mutant chickens.

Harris says: ‘Looking at an embryonic 14-day-old head, I came across the beak and these structures that were not supposed to be there.’

Could they really be teeth? Peeling away the beak in this tiny, mutant bird, the academics revealed sabreshaped formations almost identical to embryonic alligator teeth.

Next, Harris and Fallon attempted to trigger the formation of teeth in a normal chicken, by injecting the embryo with a virus designed to ‘turn on’ the relevant gene.

It was a long shot.

‘Making a tooth is complex,’ says Harris. ‘So the idea of turning on one gene that might be able to do this in an animal that hasn’t made teeth in over 70 million years, was somewhat of a stretch.’

Examining the growing embryo two weeks later, he called colleagues to look at what had happened.

‘You could see very clearly paired structures on the lower jaw.

'And so, a normal chicken can actually grow teeth.’

This was unexpected. Furthermore, the teeth had the same curved shape as dinosaur

Following this, Harris and Fallon began to find other dinosaur traits in the DNA of birds, such as scales.

They looked at an ancient Chinese breed of chicken called a Silkie.

It has primitive plumage similar to that believed to grow on some dinosaurs.

By activating a dormant gene, Harris and Fallon attempted to ‘trick’ the chicken’s leg into growing feathers instead of scales.

It worked — they had uncovered the genetic changes that had taken place as the dinosaur evolved into a bird.

Meanwhile, in Canada, Larsson had found that the three-fingered dinosaur claw structure remains hidden within a bird’s wing to this day.

‘The dinosaur fingers are adapted for grasping and snatching prey,’ he explains.

‘If we compare this to modern birds, we see the same structures in their wings but adapted for flight.’

With further research, he believes scientists should be able to transform a bird’s wing back into a dinosaur arm.

So, will it one day be possible to reverse evolution?

Mark Westhusin is a world-renowned expert in creating life forms from DNA.

Together with his colleague, Dewey Kramer, at Texas A&M University, he has cloned more species than researchers at any other laboratory, including a White-tailed deer and a Black Angus bull.

Westhusin explains that soon, the relevant DNA to turn back the clock could be manufactured and implanted into an emu egg, for instance, to trigger dormant genes.

‘We already have small artificial chromosomes that have been put into embryos and develop and divide and express their genes,’ he explains.

‘The technology is advancing so fast, in sequencing genes and in putting genes back together, and in manufacturing long stretches of DNA.’

Larsson now believes that in a hundred years or so, geneticists could retro-engineer animals that appear identical to Mesozoic dinosaurs.

‘Why can’t we take all the genetics, just change it around a little bit, and produce a Tyrannosaurus Rex, or something that looks like one?’ he asks.

‘I think that kind of scenario is quite possible. Maybe sooner than we think.’

Fallon agrees, saying: ‘As we learn more, we’ll be able to do it.

'The genetic knowledge is in the bird.’

For his part, Horner imagines creating the first example.

‘I have to admit that I’ve certainly imagined walking up on a stage to give a talk, and having a little dino chicken walk up behind me,’ he says.

‘That would be kind of cool.

‘There is now nothing to stop us bringing back dinosaurs but ourselves.

'People who don’t believe it don’t know much about evolution.’

Pausing for a second, he adds: ‘Whether it is a good idea or not is another question...’

■ DINOSAURS: Return To Life? premieres on the Discovery Channel tomorrow at 4pm.

Original here

Scientists find bugs that eat waste and excrete petrol

Silicon Valley is experimenting with bacteria that have been genetically altered to provide 'renewable petroleum'

Some diesel fuel produced by genetically modified bugs

Some diesel fuel produced by genetically modified bugs

Image :1 of 3

“Ten years ago I could never have imagined I’d be doing this,” says Greg Pal, 33, a former software executive, as he squints into the late afternoon Californian sun. “I mean, this is essentially agriculture, right? But the people I talk to – especially the ones coming out of business school – this is the one hot area everyone wants to get into.”

He means bugs. To be more precise: the genetic alteration of bugs – very, very small ones – so that when they feed on agricultural waste such as woodchips or wheat straw, they do something extraordinary. They excrete crude oil.

Unbelievably, this is not science fiction. Mr Pal holds up a small beaker of bug excretion that could, theoretically, be poured into the tank of the giant Lexus SUV next to us. Not that Mr Pal is willing to risk it just yet. He gives it a month before the first vehicle is filled up on what he calls “renewable petroleum”. After that, he grins, “it’s a brave new world”.

Mr Pal is a senior director of LS9, one of several companies in or near Silicon Valley that have spurned traditional high-tech activities such as software and networking and embarked instead on an extraordinary race to make $140-a-barrel oil (£70) from Saudi Arabia obsolete. “All of us here – everyone in this company and in this industry, are aware of the urgency,” Mr Pal says.

What is most remarkable about what they are doing is that instead of trying to reengineer the global economy – as is required, for example, for the use of hydrogen fuel – they are trying to make a product that is interchangeable with oil. The company claims that this “Oil 2.0” will not only be renewable but also carbon negative – meaning that the carbon it emits will be less than that sucked from the atmosphere by the raw materials from which it is made.

LS9 has already convinced one oil industry veteran of its plan: Bob Walsh, 50, who now serves as the firm’s president after a 26-year career at Shell, most recently running European supply operations in London. “How many times in your life do you get the opportunity to grow a multi-billion-dollar company?” he asks. It is a bold statement from a man who works in a glorified cubicle in a San Francisco industrial estate for a company that describes itself as being “prerevenue”.

Inside LS9’s cluttered laboratory – funded by $20 million of start-up capital from investors including Vinod Khosla, the Indian-American entrepreneur who co-founded Sun Micro-systems – Mr Pal explains that LS9’s bugs are single-cell organisms, each a fraction of a billionth the size of an ant. They start out as industrial yeast or nonpathogenic strains of E. coli, but LS9 modifies them by custom-de-signing their DNA. “Five to seven years ago, that process would have taken months and cost hundreds of thousands of dollars,” he says. “Now it can take weeks and cost maybe $20,000.”

Because crude oil (which can be refined into other products, such as petroleum or jet fuel) is only a few molecular stages removed from the fatty acids normally excreted by yeast or E. coli during fermentation, it does not take much fiddling to get the desired result.

For fermentation to take place you need raw material, or feedstock, as it is known in the biofuels industry. Anything will do as long as it can be broken down into sugars, with the byproduct ideally burnt to produce electricity to run the plant.

The company is not interested in using corn as feedstock, given the much-publicised problems created by using food crops for fuel, such as the tortilla inflation that recently caused food riots in Mexico City. Instead, different types of agricultural waste will be used according to whatever makes sense for the local climate and economy: wheat straw in California, for example, or woodchips in the South.

Using genetically modified bugs for fermentation is essentially the same as using natural bacteria to produce ethanol, although the energy-intensive final process of distillation is virtually eliminated because the bugs excrete a substance that is almost pump-ready.

The closest that LS9 has come to mass production is a 1,000-litre fermenting machine, which looks like a large stainless-steel jar, next to a wardrobe-sized computer connected by a tangle of cables and tubes. It has not yet been plugged in. The machine produces the equivalent of one barrel a week and takes up 40 sq ft of floor space.

However, to substitute America’s weekly oil consumption of 143 million barrels, you would need a facility that covered about 205 square miles, an area roughly the size of Chicago.

That is the main problem: although LS9 can produce its bug fuel in laboratory beakers, it has no idea whether it will be able produce the same results on a nationwide or even global scale.

“Our plan is to have a demonstration-scale plant operational by 2010 and, in parallel, we’ll be working on the design and construction of a commercial-scale facility to open in 2011,” says Mr Pal, adding that if LS9 used Brazilian sugar cane as its feedstock, its fuel would probably cost about $50 a barrel.

Are Americans ready to be putting genetically modified bug excretion in their cars? “It’s not the same as with food,” Mr Pal says. “We’re putting these bacteria in a very isolated container: their entire universe is in that tank. When we’re done with them, they’re destroyed.”

Besides, he says, there is greater good being served. “I have two children, and climate change is something that they are going to face. The energy crisis is something that they are going to face. We have a collective responsibility to do this.”

Original here

Stem-cell treatment helps restore eye-sight

Six blind patients have had their eye-sight restored after undergoing pioneering stem cell transplants.
Researchers at Moorfields Eye Hospital in London treated the patients as part of a clinical trial on patients who have lost their sight from chemical accidents or a rare genetic disease.

Using stem cells from tissue donors, surgeons grew the cells in the laboratory before transplanting them onto the patients' eyes.

Dr Julie Daniels, who is leading the research team, will present the results at a conference on regenerative medicine being held in Welwyn Garden City, Hertfordshire, today.

She said: "Before the surgery the patients were barely able to recognise when someone was waving a hand in front of their face but we have restored their vision to the point they can read three to four lines down the eye chart."

Nineteen patients have now received the treatment, known as limbal stem cell therapy, at Moorfields Eye Hospital.

The patients were chemical burn victims or sufferers of a rare genetic disease known as aniridia. They had injuries to the limbal cells in their eyes, which are under the eye lid and maintain the transparent layer on the outside of the cornea.

Dr Daniels said: "Their cornea becomes opaque, blood vessels grow across it and their eyes become inflamed and they can't see anymore. It is very painful.

"By replacing the limbal stem cells, the cornea begins to clear up as the cells are replaced with the healthy transparent layer again.

"We can't restore sight completely yet as the material we are growing the stem cells on is slightly opaque, but patients are certainly reporting an improvement."

Ten patients were given the transplant 32 months ago and six of those have showed remarkable recovery. The remaining nine patients were treated eight months ago and are still to have their recovery assessed.

Scientists at Moorfields Eye Hospital are also hoping to use stem cells to treat other causes of blindness by creating small patches of retina cells, which detect light at the back of the eye.

The Royal National Institute for the Blind (RNIB) welcomed the results of the limbal cell trial.

Barbara McLaughlin, campaigns manager at RNIB, said: "Anything that can restore sight to people who thought they had irretrievably lost their eyesight is a major step forward.

"This research is very exciting, but we would caution that these treatments can take a significant amount of time and research before they can be widely used."

More than 250,000 people suffer injuries to their eyes every year as a result of accidents, although only a small proportion of these are due to burns.

Original here

Gold Nanoparticles Go Couture

Nano-Dyed Fabric
The Latest Thing?

Marino wool is about to go high-fashion.

By adding nanoparticles made of pure gold and silver to fine Marino wool, researchers in New Zealand have created a rainbow of unexpected colors intended for high-end, couture fashion designers.

They unveiled the first scarf dyed with gold nanoparticles last week at the Nano Science and Technology Institute convention in Boston.

"We want to create a fashion icon, like Louis Vutton or Gucci, where the logo will speak for itself," said James Johnston, the lead researcher from Victoria University in New Zealand.

"You could say that you are clothed in pure gold or silver," said Johnston.

The dyed wool is not gold or silver in color, however. When dyed with gold nanoparticles, wool, or just about any other fabric for that matter, ranges from purple to yellow and everything in between.

Silver nanoparticles create bright yellows, greens and oranges.

The researchers can even combine and mix colors to create new ones. Varying the amount of gold or silver nanoparticles determines the shade's intensity.

The color of the wool depends on the type of precious metal used, the size of the nanoparticles, and in some cases, their shape.

Spherical gold nanoparticles about 10 nanometers across create a red wine color. As their size increases to 100 nanometers, the color turns red, then purple, blue, and finishes off in various shades of gray.

"Silver nanoparticles are a bit trickier," said Johnston.

Sizes and shapes determine the color of silver nanoparticles, which can be spheres, triangles, round plates or even prisms. They can be shades of green, yellow or orange.

Besides the cachet that comes with clothing yourself in precious metal, Johnston also claims that the process is environmentally friendly, an advantage over traditional dyes.

The wool is also fade-free, handles abrasion well and eliminates static electricity, said Johnston. The gold nanoparticles never wash out.

Besides, "it's very soft and has a nice appearance with a subtle color," he added.

Precious-metal nanoparticles are not new. Gold nanoparticles have been used unwittingly for centuries in red stained-glass windows and are being explored for their potential medical benefits.

Over the last decade, silver nanoparticles have been added to everything from socks to teddy bears for their antibacterial properties, despite recent findings that suggest their leakage into water systems.

Precious-metal-dyed wool isn't for the everyday buyer, and a gold- or silver-dyed wool sweater will be at least several times more expensive than the average wool sweater. Johnston estimates that a scarf made of the wool, which was displayed at the conference "hot off the loom," will cost between $200 and $300.

"It's the difference between a BMW and a Toyota," said Johnston.

While Johnston won't mention which specific fashion designers he is in talks with, he hopes that the first precious metal dyed garments will appear in a year or so.

"This is very interesting research," said Kevin Conley, a nanotechnology researcher at Forsyth Technical Community College who attended Johnston's presentation but was not involved in the work.

"I think this will put a smile on people's faces and help advance nanotechnology," said Conley.

Original here

We may all be space aliens: study

PARIS (AFP) - Genetic material from outer space found in a meteorite in Australia may well have played a key role in the origin of life on Earth, according to a study to be published Sunday.

European and US scientists have proved for the first time that two bits of genetic coding, called nucleobases, contained in the meteor fragment, are truly extraterrestrial.

Previous studies had suggested that the space rocks, which hit Earth some 40 years ago, might have been contaminated upon impact.

Both of the molecules identified, uracil and xanthine, "are present in our DNA and RNA," said lead author Zita Martins, a researcher at Imperial College London.

RNA, or ribonucleic acid, is another key part of the genetic coding that makes up our bodies.

These molecules would also have been essential to the still-mysterious alchemy that somehow gave rise, some four billion years ago, to life itself.

"We know that meteorites very similar to the Murchison meteorite, which is the one we analysed, were delivering the building blocks of life to Earth 3.8 to 4.5 billion years ago," Martins told AFP in an interview.

Competing theories suggest that nucleobases were synthesised closer to home, but Martins counters that the atmospheric conditions of early Earth would have rendered that process difficult or impossible.

A team of European and US scientists showed that the two types of molecules in the Australian meteorite contained a heavy form of carbon -- carbon 13 -- which could only have been formed in space.

"We believe early life may have adopted nucleobases from meteoric fragments for use in genetic coding, enabling them to pass on their successful features to subsequent generations," Martins said.

If so, this would have been the start of an evolutionary process leading over billions of years to all the flora and fauna -- including human beings -- in existence today.

The study, published in Earth Planetary Science Letters, also has implications for life on other planets.

"Because meteorities represent leftover materials from the formation of the solar system, the key components of life -- including nucleobases -- could be widespread in the cosmos," said co-author Mark Sephton, also at Imperial College London.

"As more and more of life's raw materials are discovered in objects from space, the possibility of life springing forth wherever the right chemistry is present becomes more likely," he said.

Uracil is an organic compound found in RNA, where it binds in a genetic base pair with another molecule, adenine.

Xanthine is not directly part of RNA or DNA, but participates in a series of chemical reactions inside the RNA of cells.

The two types of nucleobases and the ratio of light-to-heavy carbon molecules were identified through gas chromatography and mass spectrometry, technologies that were not available during earlier analyses of the now-famous meteorite.

Even so, said Martins, the process was extremely laborious and time-consuming, one reason it had not be carried out up to now by other scientists.

Original here