Scientists throw water on astronomer’s claims about alien life on Philae’s comet

Evidence that a comet carrying a European spacecraft is home to an abundance of microbial life “is flimsy at best,” according to The Guardian.

Astrobiologist Chandra Wickramasinghe said the comet, named 67P/Churyumov-Gerasimenko, had an organic-rich black crust that was most likely explained by organisms living beneath the icy surface, reported The Guardian on Monday.

But The Guardian later reported that the vast majority of experts agreed that there’s no evidence of any life on the comet.

“No scientist active in any of the Rosetta instrument science teams assumes the presence of living micro-organisms beneath the cometary surface crust,” Uwe Meierhenrich, an analytical chemist at the University of Nice Sophia Antipolis in France, told The Guardian.

“Scientists are rightly fascinated by the search for life elsewhere, and the possibility of the delivery of life to Earth from elsewhere remains an intriguing line of enquiry. However all measurements from Rosetta or by Earth-based telescopes on comets can be explained by much simpler chemical and physical processes than involving extra-terrestrial life,” said Professor Alan Fitzsimmons of Queens University, according to the Christian Science Monitor.

Continued ...

Jupiter moon 'holds magma ocean'

By Jonathan Amos Science correspondent, BBC News

One of Galileo's iconic images of Io in which a giant volcanic plume rises high above the moon

Io is the most volcanic world in the Solar System and scientists think they now have a better idea of why that is.

The moon of Jupiter erupts about 100 times more lava on to its surface each year than does Earth.

A re-assessment of data from Nasa's Galileo probe suggests all this activity is being fed from a giant magma ocean under Io's crust.

Researchers tell Science magazine that this blisteringly hot reservoir is probably some 50km (30 miles) thick.

And that figure is a minimum. It could be much, much thicker, says the study's lead author, Krishan Khurana, who is affiliated to UCLA's Institute of Geophysics and Planetary Physics.

"When scientists first started looking at the images of Io from the Pioneer and Voyager spacecraft in the late 70s, the moon appeared so alien," he told the BBC.

"Right away, the scientists were asking questions; and one of the questions was, 'why are volcanoes present all over the surface?' Well, it's because there's a giant aquifer of magma present right beneath the crust. That's what our study is telling us."

Io's volcanism is driven by its parent planet - Jupiter. The great gas giant's enormous bulk produces colossal tides on the moon that squeeze and pull its body, melting its rocks.

The distribution of volcanoes on Io is quite different to that on Earth, however. They are everywhere, whereas on Earth the volcanoes tend to be collected at the boundaries of tectonic plates, the huge slabs of cold rock that cover our planet's surface.

Nasa's Galileo probe, following up the observations of the Pioneer and Voyager spacecraft, made seven close passes of the moon.

Readings from its magnetometer instrument indicated the moon was dramatically distorting Jupiter's magnetic field - but what was going on inside Io to produce the effect was not clear.

Continue reading the main story

NASA'S GALILEO SPACECRAFT

• Galileo was launched from the space shuttle Atlantis in 1989.
• It encountered several asteroids on the way to Jupiter, arriving in 1995.
• Galileo became the first spacecraft to enter orbit around Jupiter
• Its tour included close encounters with the Galilean moons - Io included
• Galileo ended its mission by plunging into the Jovian atmosphere in 2003

It has taken several years to work through the problem and identify the solution, and it comes down to the nature of the rock in the moon and how it behaves when it melts.

Dr Khurana explained: "The data was available almost seven or eight years ago. However, we could not at that time explain what we were seeing.

"Later experiments in mineral physics found out that when ultramafic rocks, which are rocks very high in magnesium and iron - when those are melted, their conductivity shoots up by orders or magnitude. And it is that very high conductivity that can create the type of signature we have seen. So, we needed mineral physics to catch up with our data."

Tests have shown that the signatures detected by Galileo are consistent with a rock like lherzolite, an igneous rock rich in silicates of magnesium and iron. You find this rock, for example, in Scandinavia.

The picture emerging of Io is of a world that apes a body considerably bigger in size.

Its magma ocean layer is at least 50km thick, and probably makes up at least 10% of the moon's mantle by volume. Its temperature probably exceeds 1,200C.

This aquifer sits under the crust, some 50km down. The mantle - the moon's interior mid-layer - probably extends for a further 700-800km. And at the core? Gravity measurements suggest it is made of iron and possibly liquid - much like the Earth.

"The moon in size is only about one-fortieth the volume of the Earth; in mass it's only one-sixtieth," said Dr Khurana.

"And yet because of the tremendous amount of heat generated by tides that Jupiter raises on this very small moon, its internal structure is very similar to the Earth or a bigger planet that has a lot of tectonics on it."

http://www.bbc.co.uk/news/science-environment-13378864

Alien-life claims spark monster mud-slinging

Are these tubules evidence of alien life?
(Image: Richard B. Hoover/Journal of Cosmology)

13:34 08 March 2011 by Ferris Jabr

First seen on 14 May 1864, in the shape of an enormous fireball in the sky over southern France, the Orgueil meteorite is making headlines again – though this time its appearance has mostly been ill-received.

Last week, NASA scientist Richard Hoover at the Marshall Space Flight Center near Huntsville, Alabama, published a paper in the Journal of Cosmology claiming that fragments collected from the Orgueil meteorite and two similar meteorites contain fossilised bacteria.

Hoover made nearly identical claims in 2004 and again in 2007. This time, Hoover says that fibrous structures in the meteorites are almost exactly the same size and shape as photosynthetic bacteria found on Earth, especially one relatively large bacterium called Titanospirillum velox.

Macaroni, anyone?

Hoover fractured pieces of the Orgueil meteorite, two other CI1 carbonaceous chondrites – a rare class of meteorite of which there are only nine known specimens – and used an imaging technique called field emission scanning electron microscopy to closely study the interiors of the fragments.

In his paper, he juxtaposes pictures of tubular and ribbon-like squiggles on the inner surface of the space rocks and pictures of bacteria found on Earth. They all look like black-and-white photos of dried macaroni.

In addition to this shape-based evidence, Hoover provides chemical evidence, arguing that the squiggles contain more carbon than the meteorite matrix in which they are suspended, suggesting they were once alive.

Scientists are currently debating whether there is enough evidence to accept that the filamentous structures inside the meteorites are, as Hoover claims, biological organisms from outer space, whether they are in fact terrestrial bacteria that wormed their way into the meteorite after it crashed or whether the squiggles are nothing more than naturally occurring mineral structures that, to an eager researcher's eye, may very well look like bacteria. So far, the consensus is that the last of these possibilities adheres most closely to principle of Occam's razor.

See what you want

Microbiologist Rosie Redfield at the University of British Columbia, Vancouver, critiqued Hoover's study on her blog, RRResearch. She remains unconvinced by the evidence for alien life presented in the study. Although Redfield chastises Hoover for not properly detailing how the samples were stored over the years – and therefore how they could have been contaminated by earthly bugs – she is more concerned that Hoover apparently did little to rule out the possibility that the shapes he saw are simply not life forms, extraterrestrial or otherwise.

"The first thing you learn when you do electron microscopy is that it's really easy to see anything you are looking for – if you have a good search image in your brain, you can find it," she says. "I think those squiggles are just places in the rock where the minerals happened to arrange themselves in a squiggle shape. Minerals readily grow into fibres."

The often confounding prevalence of minerals that look an awful lot like living things is exactly what geologist Alison Olcott Marshall at the University of Kansas in Lawrence confronted in a Nature paper published last month.

Look closer

Olcott Marshall and her colleagues revealed that what we thought were the oldest known bacterial fossils on Earth are only deceptive patterns formed in the rock by geological processes. The researchers sliced the 3.5-billion-year old Apex Chert rock containing the alleged fossils into 30-micrometre sections, thinner than any previously studied slices, and shone a powerful laser at them to get a good look under the microscope.

The new analysis confirmed that the fibrous structures researchers had originally identified as fossilised cyanobacteria were in fact fractures in the rock filled with inorganic haematite and quartz.

"One lesson we learn over and over again is that morphology is very common between minerals and life," says Olcott Marshall, who is also unconvinced by Hoover's new paper. "Finding circles and wiggles is not necessarily evidence of life."

Not feeling the chemistry

Olcott Marshall is not only highly sceptical of the morphological evidence, she is disappointed by Hoover's chemical evidence. "I really wish there was more evidence separating the composition of these structures from the carbonaceous chondrite around them," she says.

"It looks like some squiggles have more sulphur and less silica than the background rocks, but to my eye the data show that nitrogen, oxygen, carbon and phosphorous are all evenly dispersed." If the tubules were in fact life forms, these organic compounds should be present in higher quantities wherever a squiggle graces the rock, she says.

Redfield says that Hoover explains away the lack of nitrogen in the squiggles by claiming that they are fossils and that even fossils on Earth do not contain much nitrogen. But if the Orgueil meteorite does in fact conceal fossilised bacteria, there is still the question of where these bacteria came from in the first place and how they apparently managed to live inside a meteorite hurtling through space.

Not so bright

Hoover compares the structures inside the meteorite to cyanobacteria, which require light and water to produce food through photosynthesis. Although the meteorite does contain water and may have originated on an icy comet, its interior is not exactly the brightest environment around. If the squiggles are bacteria from Earth, it is unclear how they would have fossilised between 1864 and now.

This is not the first time that scientists have grappled with the immense difficulty of interpreting lifelike structures they sometimes find within meteorites. In 1996 David McKay of NASA's Johnson Space Center in Houston, Texas, published a paper in Science claiming that a meteorite called Allan Hills 84001 contained fossilised Martian microbes. The announcement caused such a hullaballoo in the scientific community, media and public alike that President Bill Clinton promptly delivered a televised public address.

Scepticism about those findings mushroomed: some researchers argued that the nanometre-scale filaments were too small to be living things – even bacteria – while others thought contamination by terrestrial microbes was a simpler explanation than Martian life. Today, 15 years later, scientists are still debating whether Allan Hills 84001 harbours tiny hitchhikers from the Red Planet.

Worlds at our feet

Scientists seize the opportunity to examine meteorites for signs of alien life because rocks that fall from space bring pieces of other worlds to our feet – which is quite a bit easier than travelling all the way to Mars or trying to scoop a passing comet into a space station.

But even with tools that let them examine meteorites in exquisite detail, researchers cannot easily distinguish a squiggle in a rock from the remains of a living creature, which begs the question: what is the gold standard for evidence of alien life? Assuming that a little green man is not going to drop by NASA's headquarters any time soon, what will convince scientists that they have found extraterrestrial life?

The answer, it seems, is nothing short of "extraordinary evidence" – a phrase that is currently leaping from the lips of scientists around the world as they argue over Hoover's new study.

Gold standard

"As for the gold standard, supposed fossils would be low on the list," said Jeffrey Bada, a geochemist at the Scripps Institution of Oceanography in La Jolla, California. "There are just too many non-biological artefacts. The not-so-short answer is that several different lines of evidence are going to be required."

Olcott Marshall agrees. "Morphology alone isn't enough; geological context isn't enough – you need all the pieces. You need multiple lines of evidence: morphology that is highly reminiscent of biology, a geological context that makes sense and strong chemical evidence."

In the specific case of Hoover's new study, none of these threads of evidence is particularly taut. "This newest paper is very similar to his older papers and to the best of my knowledge there is no support in the meteorite analysis community for the rather extraordinary claim that what he is seeing is alien life," says Carl Pilcher, director of the NASA Astrobiology Institute in Mountain View, California.

Media storm

More than a few scientists and journalists have argued that the evidence Hoover does offer is all the more ensconced in suspicion – though certainly not invalidated – by the journal in which he chose to publish: the peer-reviewed, open access Journal of Cosmology, which announced it is likely to go out of business in a few month's time.

The journal's editor-in-chief, Harvard University's Rudy Schild, is a proponent of panspermia – the idea that life abounds in the universe and that a meteorite crawling with alien organisms likely seeded life on Earth.

The journal has startled and confused the media with a series of atypical press releases that, for example, defend Hoover's choice to publish with the Journal of Cosmology instead of Science or Nature because "Editors at Science have been accused of using the Bible to make editorial decisions". It also alleges anti-competitive practices have been aimed at the Journal of Cosmology, and accuses other media outlets of plagiarism.

Back and forth

In an official press release, NASA distanced itself from Hoover's findings: "NASA cannot stand behind or support a scientific claim unless it has been peer-reviewed or thoroughly examined by other qualified experts. This paper was submitted in 2007 to the International Journal of Astrobiology. However, the peer review process was not completed for that submission. NASA also was unaware of the recent submission of the paper to the Journal of Cosmology or of the paper's subsequent publication."

However, the Journal of Cosmology's editorial guidelines state that all articles are peer reviewed. In an email to New Scientist, the journal's managing director Lana Tao explained that Hoover's article was first submitted in November 2010, reviewed by Chandra Wickramasinghe, who requested certain changes and sent out for external review by five experts.

Hoover then revised the paper and it was subsequently reviewed by two external referees, who requested minor revisions. None of the external reviewers have been named.

Hoots and jeers

In a move unusual for research journals, the Journal of Cosmology sent 100 requests for additional review and analysis from scientists and has published 21 responses so far, most of which largely applaud Hoover's study, raising minor quibbles here and there.

It could all yet prove to be a tempest in a teacup, though. It appears likely that Hoover's study may soon be ignored by the majority of the scientific community, instead of enjoying a healthy debate such as that raised by McKay's 1996 paper on the Mars meteorite. Redfield says that a microbiologist that she knows refused to read it.

The Journal of Cosmology, however, does not show signs of backing down. "It should be expected that a discovery as momentous as reported by Dr. Richard Hoover, would be met with hoots and jeers," said Lana Tao in another email. "The choice is simple: Scientific discourse vs psychosis. Hysteria and lies do not constitute scientific doubt. They are calls for medication."

http://www.newscientist.com/article/dn20222-alienlife-claims-spark-monster-mudslinging.html

Fossil Life in Meteorite?

Journal of Cosmology, 2011, Vol 13,
JournalofCosmology.com March, 2011

Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites
Richard B. Hoover, Ph.D. NASA/Marshall Space Flight Center

Synopsis
Dr. Hoover has discovered evidence of microfossils similar to Cyanobacteria, in freshly fractured slices of the interior surfaces of the Alais, Ivuna, and Orgueil CI1 carbonaceous meteorites. Based on Field Emission Scanning Electron Microscopy (FESEM) and other measures, Dr. Hoover has concluded they are indigenous to these meteors and are similar to trichomic cyanobacteria and other trichomic prokaryotes such as filamentous sulfur bacteria. He concludes these fossilized bacteria are not Earthly contaminants but are the fossilized remains of living organisms which lived
in the parent bodies of these meteors, e.g. comets, moons, and other astral bodies. The implications are that life is everywhere, and that life on Earth may have come from other planets.

Members of the Scientific community were invited to analyze the results and to write critical commentaries or to speculate about the implications. These commentaries will be published on March 7 through March 10, 2011.

Official Statement from Dr. Rudy Schild,
Center for Astrophysics, Harvard-Smithsonian,
Editor-in-Chief, Journal of Cosmology.

Dr. Richard Hoover is a highly respected scientist and astrobiologist with a prestigious record of accomplishment at NASA. Given the controversial nature of his discovery, we have invited 100 experts and have issued a general invitation to over 5000 scientists from the scientific community to review the paper and to offer their critical analysis. Our intention is to publish the commentaries, both pro and con, alongside Dr. Hoover's paper. In this way, the paper will have received a thorough vetting, and all points of view can be presented. No other paper in the history of science has undergone such a thorough analysis, and no other scientific journal in the history of science has made such a profoundly important paper available to the scientific community, for comment, before it is published. We believe the best way to advance science, is to promote debate and discussion.

Full paper and pictures at: http://journalofcosmology.com/Life100.html

Now you don't... The never-ending search for life on Mars continues

Dec 29th 2010

TOWARDS the end of 2011 a large and hugely expensive robotic rover called Curiosity is due to blast off for Mars from Cape Canaveral. If it makes it safely to the planet’s surface in August 2012 (getting down from orbit in one piece has not always proved easy for space probes) one of the first things it will do is sniff the air. Its creators, back on Earth, will be straining to see if that air carries a whiff of methane.

In 2004 three different groups said they had seen signs of methane in the atmosphere of Mars. Since, on Earth, almost all atmospheric methane comes from living things, this provided the biggest news from the planet since ALH 84001, a meteorite purportedly bearing Martian fossils, created headlines in 1996.

The shimmering phantasm that is Martian life helps explain why the exploration of Mars soaks up more effort and expenditure than any other branch of planetary science. The barren, arid, radiation-slaked landscape revealed by early probes put to rest the idea that there might be anything living on the Martian surface. But some people hope there are living things below this inhospitable exterior. Methane would be evidence in favour of that. Thoughts of the gas have therefore shaped Curiosity’s scientific programme—and in 2016 the first Mars mission to bring together NASA, America’s space agency, and ESA, its European counterpart, is to be devoted to analysing trace gases in the atmosphere, with methane the star attraction.

Natural gas?

There have, though, always been doubts about Martian methane. As with ALH 84001 the eye of faith has, in the view of sceptics, been too willing to interpret observations in the most favourable light—and when observations are as strikingly hard to make as those which seek traces of gas in a thin atmosphere so far away, lighting can be everything.

Those views have now been given a particularly thoroughgoing expression in a paper in Icarus by Kevin Zahnle, a planetary scientist at NASA’s Ames Research Centre, in California, and two colleagues. This paper is not the last word on the subject, but the case it assembles is a powerful one, ranging from spectroscopic minutiae to a close look at how hard it is to fit the methane data into what is known about Mars as a whole.

One of the things that everyone agrees about methane on Mars is that it has to be short-lived. Though Mars has relatively little oxygen in its atmosphere (just 0.13% of the total) that atmosphere nonetheless provides what chemists call oxidising power, which gives it the ability to pull methane molecules to pieces. The predicted lifetime of Martian methane, based on observations of the Earth’s atmosphere and experiments in laboratories, is just 300 years. This is one of the reasons why methane was seen as an exciting discovery—its constant oxidation in the atmosphere means it would have to be replenished by some occult process. Even if there was no life involved that would, at least, require that some novel chemistry was going on.

The problem is that observations of methane on Mars imply that its lifetime must be far shorter than a few hundred years. They indicate that the gas comes and goes on a seasonal basis, with much more of it around at some times and places than others. If methane waxes and wanes with the seasons, then its lifetime must be on a par with the length of a season—several months, not several centuries.

Various suggestions as to how this might be possible have been made. There could be special catalysts in the soil, for example, perhaps created by the static electricity whipped up by dust devils. Dr Zahnle and his colleagues argue that such ideas merely pass the buck. Whatever oxidises the methane would itself get used up in the process, and so would also need to be replenished. To oxidise the methane at a high rate the planet would need to make new oxidising chemicals at that same high rate. There is no evidence of its doing so.

The known way in which oxidising power gets added to the Martian atmosphere is through the destruction of water molecules by ultraviolet light. This creates hydrogen and oxygen. Left to themselves they would recombine, producing no net change, but some of the hydrogen leaks out of the atmosphere into space, leaving oxygen—the paradigmatical oxidiser—behind. This process works too slowly, though, to account for the sudden drops seen in the methane level. Explaining these requires new ways of producing oxidising power which do nothing to alter the balance of other chemicals in the atmosphere. That seems a tall order.

There are other things which might be happening to the methane. It could be stored on the surfaces of minerals, or locked into exotic ices, or even eaten by yet more bugs. But all these, too, are inconsistent with the big picture. Mars has xenon in its atmosphere, and xenon atoms are similar enough to methane molecules that a physical process which locked up methane would lock up xenon too. Yet the xenon persists, airily unfettered. As to methane-eating bugs, a look at the planet as a whole again seems to rule that possibility out. Carbon monoxide offers a lot more energy per molecule to hungry microbes than methane does—but Mars’s carbon monoxide level is stable and much higher than the claimed methane level. Martian life might be different from terrestrial life in many ways, but it is hard to conceive of any form of life that would spurn a rich and abundant energy supply in favour of a scarce and less fulfilling one. Darwin would certainly not have approved of such pickiness.

Or just hot air?

Carl Sagan, a devoted student of Mars (and, as it happens, once an editor of Icarus), used to say that extraordinary claims need extraordinary evidence. Dr Zahnle and his colleagues show that a rapidly fluctuating level of methane is an even more extraordinary claim than has been widely appreciated. That puts a pressure on the evidence which it may not be able to bear.

The three sets of observations that purported to see methane on Mars all relied on the absorption lines which the gas imposes on light at specific wavelengths. Two of these sets of observations were made from the Earth, one from an ESA spacecraft orbiting Mars. The spacecraft’s instrument is not particularly precise, and although a model of the Martian atmosphere containing methane gives a better match to the spectra it sees than a methane-free model does, the match is not that great, and does not explain all the spectral anomalies in the data. Were these the only observations of methane on Mars, the subject would be viewed with much more scepticism.

Far more precise observations are possible from Earth. But here there is a different problem. Mars’s atmosphere is thin, and even the highest levels of methane it might contain are low. The Earth’s atmosphere is thick and contains a lot more methane. A ray of sunlight that passes down through the Martian atmosphere, bounces off the planet’s surface, goes back up through the atmosphere, traverses interplanetary space and then comes down through the Earth’s atmosphere to a mountaintop observatory encounters about 2,000 times more methane molecules on the Earthly leg of its journey than on the two Martian ones put together. That rather tends to swamp the signal.

The only thing that makes the distinctive spectral features of methane on Mars worth looking for is that spectral lines caused by methane on Mars are offset compared with the same lines caused by methane on Earth, thanks to the relative movement of the two planets. Even so, there are a great many absorption lines of other sorts that can lead to confusion, with different lines potentially masking the signal depending on whether Mars is coming or going.

There is also the problem that the carbon in methane comes in different isotopic forms, and the different forms have subtly different spectra. In some circumstances, a feature caused by a rare isotope in the Earth’s atmosphere might mimic the expected feature from normal methane on Mars. Dr Zahnle and his colleagues point out various ways that these factors could have misled observers.

The observers are not taking this criticism lying down. Michael Mumma, of NASA’s Goddard Space Flight Centre in Maryland, leads the only Earthbound team still gathering the sort of data in which Martian methane has been seen. Having served as a referee on Dr Zahnle’s paper, he withdrew from the process, saying there was too much wrong with the paper for it to be fixed. He will be writing a rebuttal soon, he says. Dr Zahnle’s team hope that it includes raw data Dr Mumma has not yet published and which might put some of the arguments to rest. Both will look forward to data from Curiosity.

In the meantime, the debate carries a worthwhile scientific lesson in itself. Observations, which to an outsider might sound like simple things, are often remarkably difficult, and depend on complex models to make any sense at all. Thomas Huxley, Darwin’s ally in the fight to get evolution accepted, spoke warmly of the facility with which ugly facts can kill beautiful theories. But that fatal ability should not hide the fact that well-applied theories, beautiful and otherwise, can play a crucial role in deciding which observations get treated as facts in the first place.

from PRINT EDITION | Science and Technology

http://www.economist.com/node/17797286

Odds of Life on Nearby Planet '100 Percent,' Astronomer Says

By Jeanna Bryner
Published September 29, 2010

| Space.com

Lynette Cook, Space.com

This artist's conception shows the inner four planets of the Gliese 581 system and their host star, a red dwarf star only 20 light years away from Earth. The large planet in the foreground is the newly discovered GJ 581g, which has a 37-day orbit right in the middle of the star's habitable zone and is only three to four times the mass of Earth, with a diameter 1.2 to 1.4 times that of Earth.

An Earth-size planet has been spotted orbiting a nearby star at a distance that would makes it not too hot and not too cold -- comfortable enough for life to exist, researchers announced Wednesday.

If confirmed, the exoplanet, named Gliese 581g, would be the first Earth-like world found residing in a star's habitable zone -- a region where a planet's temperature could sustain liquid water on its surface.[Illustration of planet Gliese 581g.]

And the planet's discoverers are optimistic about the prospects for finding life there.

"Personally, given the ubiquity and propensity of life to flourish wherever it can, I would say, my own personal feeling is that the chances of life on this planet are 100 percent," said Steven Vogt, a professor of astronomy and astrophysics at the University of California, Santa Cruz, during a press briefing today.

"I have almost no doubt about it."

His colleague, Paul Butler of the Carnegie Institution of Washington, in Washington, D.C., wasn't willing to put a number on the odds of life, though he admitted he's optimistic.

"It's both an incremental and monumental discovery," Sara Seager, an astrophysicist at the Massachusetts Institute of Technology, told SPACE.com. Incremental because the method used to find Gliese 581g already has found several planets (all super-Earths, more massive than our own world) outside their stars' habitable zone, along with non-Earth-like planets within the habitable zone.

"It really is monumental if you accept this as the first Earth-like planet ever found in the star's habitable zone," said Seager, who was not directly involved in the discovery.

Vogt, Butler and their colleagues will detail the planet finding in the Astrophysical Journal.

The newfound planet joins more than 400 other alien worlds known to date. Most are huge gas giants, though several are just a few times the mass of Earth.

Stellar tugs

Gliese 581g is one of two new worlds the team discovered orbiting the red dwarf star Gliese 581, bumping that nearby star's family of planets to six. The other newfound planet, Gliese 581f, is outside the habitable zone, researchers said.

The star is located 20 light-years from Earth in the constellation Libra. One light-year is about 6 trillion miles (10 trillion km).

Red dwarf stars are about 50 times dimmer than our sun. Since these stars are so much cooler, their planets can orbit much closer to them and still remain in the habitable zone.

Estimates suggest Gliese 581g is 0.15 astronomical units from its star, close enough to its star to be able to complete an orbit in just under 37 days. One astronomical unit is the average distance between the Earth and sun, which is approximately 93 million miles (150 million km).

The Gliese 581 planet system now vaguely resembles our own, with six worlds orbiting their star in nearly circular paths.

With support from the National Science Foundation and NASA, the scientists -- members of the Lick-Carnegie Exoplanet Survey -- collected 11 years of radial velocity data on the star. This method looks at a star's tiny movements due to the gravitational tug from orbiting bodies.

The subtle tugs let researchers estimate the planet's mass and orbital period, how long it takes to circle its star.

Gliese 581g has a mass three to four times Earth's, the researchers estimated. From the mass and size, they said the world is probably a rocky planet with enough gravity to hold onto an atmosphere.

Just as Mercury is locked facing the sun, the planet is tidally locked to its star, so that one side basks in perpetual daylight, while the other side remains in darkness. This locked configuration helps to stabilize the planet's surface climate, Vogt said.

"Any emerging life forms would have a wide range of stable climates to choose from and to evolve around, depending on their longitude," Vogt said, suggesting that life forms that like it hot would just scoot toward the light side of that line while forms with polar-bear-like preferences would move toward the dark side.

Between blazing heat on the star-facing side and freezing cold on the dark side, the average surface temperature may range from 24 degrees below zero to 10 degrees Fahrenheit (minus 31 to minus 12 degrees Celsius), the researchers said.

Are you sure?

Supposedly habitable worlds have been found and later discredited, so what makes this one such a breakthrough?

There's still a chance that further observations will dismiss this planet, also. But over the years, the radial velocity method has become more precise, the researchers point out in their journal article.

In addition, the researchers didn't make some of the unrealistic assumptions made in the past, Seager said.

For instance, another planet orbiting Gliese 581 (the planet Gliese 581c) also had been considered to have temperatures suitable for life, but in making those calculations, the researchers had come up with an "unrealistic" estimate for the amount of energy the planet reflected, Seager pointed out. That type of estimate wasn't made for this discovery.

"We're looking at this one as basically the tip of the iceberg, and we're expecting more to be found," Seager said.

One way to make this a reality, according to study researchers, would be "to build dedicated 6- to 8-meter-class Automated Planet Finder telescopes, one in each hemisphere," they wrote.

The telescopes -- or "light buckets" as Seager referred to them -- would be dedicated to spying on the nearby stars thought to potentially host Earth-like planets in their habitable zones. The result would be inexpensive and probably would reveal many other nearby potentially habitable planets, the researchers wrote.

Beyond the roughly 100 nearest stars to Earth, there are billions upon billions of stars in the Milky Way, and with that in mind, the researchers suggest tens of billions of potentially habitable planets may exist, waiting to be found.

Planets like Gliese 581g that are tidally locked and orbit the habitable zone of red dwarfs have a high probability of harboring life, the researchers suggest.

Earth once supported harsh conditions, the researchers point out. And since red dwarfs are relatively "immortal" living hundreds of billions of years (many times the current age of the universe), combined with the fact that conditions stay so stable on a tidally locked planet, there's a good chance that if life were to get a toe-hold it would be able to adapt to those conditions and possibly take off, Butler said.

Sheep attacked 'by aliens'

5 April 2010, 10:07

Unexplained sheep attacks in Shropshire have led to claims that aliens are to blame.

Farmers near Shrewsbury have found the animals dead after seemingly being "experimented on", reports The Sun.

UFO hunters are linking the mutilations - including the removal of sheep brains and eyes - to sightings of mysterious orange lights in the sky and claim to have witnessed sheep being zapped by two of the spheres.

Phil Hoyle, 53, who has spent nine years probing the riddle of livestock found killed, said: "For a short while it looked more like a Star Wars battle."

He also interviewed farmers and "all but one had had some type of unusual disappearance of animals or deaths with strange injuries".

The retired steelworker added: "Animals are being clinically and surgically sampled by a highly advanced technology."

http://web.orange.co.uk/article/quirkies/sheep_attacked_by_aliens

‘Earths are common,’ NASA scientist says

Published On Thu Mar 18 2010

Cathal Kelly
Staff Reporter

We are surrounded by dozens of habitable planets. We just can’t see them yet, according to a researcher.

In his new book, How to Find a Habitable Planet, geoscientist Jim Kasting suggests that the chances that each of the stars you see in the sky is being rotated by a planet capable of sustaining life are surprisingly high.

Kasting is the chair of NASA’s Exoplanet Exploration Program Analysis Group.

“I’m very optimistic. I think Earths are common,” Kasting said. “If you take any given type of solar star, the chances of finding an Earth-like planet are reasonably good … the odds (of any star being orbited by a habitable planet) might be somewhere between a tenth and a half.”

Let’s put that into perspective. The closest star to our solar system is Alpha Centauri. It’s more than four light years away. That’s about 40 trillion kilometres.

We don’t as yet know if an Earth-like planet orbits Alpha Centauri because we can’t see clearly enough. Stars are very bright. Planets are very dim. One washes out the other.

So this search starts out very basically. Kasting’s initial checklist for habitable planets contains only two boxes.

First, there is its composition – it must be a rock, like Earth, as opposed to gaseous, like Jupiter. Second, it must occupy the proper distance from its sun, so that any incipient life is neither baked nor frozen.

“We think it also needs liquid water … we don’t know for sure that life requires liquid water. We just know that all terrestrial life does,” Kasting said.

The chances increase if scientists are able to detect carbon dioxide, oxygen, ozone and gases like methane or nitrous oxide which are produced by organisms – at least as we currently define them. It stands to reason that the planet should be about the same size as our own.

The current methods of discovering planets cue on the stars they orbit around. The most common is Doppler spectroscopy – observing small shifts in the star’s own orbit and speed relative to Earth caused by the gravitational force exerted by the unseen planet.

Using this blunt instrument, scientists have thus far discovered about 400 planets outside our own solar system. Most of those are gigantic – the size of Jupiter or so – and unlikely for a variety of reasons to fit the habitation bill.

However, we’ve made some recent strides in detection methods. The advent of powerful space-based telescopes increases the sharpness of our view, and expands the astronomer’s tool box.

“What we really need … are telescopes called Terrestrial Planet Finders,” said Kasting. TPF’s can work in the visible or infrared spectrum. A visible spectrum TPF probably requires an aperture of 8 m, which is more than three times bigger than the Hubble telescope.

“The difficult thing is to look at an area very close to a bright star, and block out the light so that you just see the light from the planet,” Kasting said.

The best method, according to Kasting, is to build two craft – one housing the telescope, and the other comprised of a shield to block out light that floats at an angle above the first craft.

The technology to build such devices exists. But the money does not.

There is currently a telescope in space doing the number crunching that might precede TPFs. The Kepler telescope has been in space for about a year searching for, amongst other things, statistical evidence of Earth-like planets.

Kepler is staring at one small patch of the vast Milky Way, monitoring the brightness of 150,000 stars. If an Earth-sized planet passes in front of any of those stars, the nearly imperceptible dimming will be captured by Kepler. There’s an element of luck involved, but once that data is interpreted, Kasting’s 10-50 per cent educated guess will have an empirical benchmark.

“There’s lots of activity. Kepler’s up there now. (Another, better space telescope) SIM Lite could be up there, if the astronomers choose to fund it in the next few years. And TPF - we actually got started building one of those three or four years ago. Until the money ran out.”

Where are we now?

“SIM is sitting in (NASA’s California-based) Jet Propulsion Laboratory, half-finished … They’ve designed the hardware. It could be built very quickly … If they got funding this year, they could launch it in about four years from now.”

SIM is specifically designed to search for Earth-sized planets.

If Kasting’s theories bear fruit, this might provide an entirely new rationale for deep-space exploration. But if TPFs are a ways off, that’s a task of an entirely different order of difficulty.

“I’m a science fiction fan, too. Maybe we’ll get there someday. But that’s well off into the future,” Kasting said. “I’m most interested in what we can do now – which is look at these planets, and try to figure out if they’re habitable, and then, if they’re inhabited.”

http://www.thestar.com/news/sciencetech/article/781654--earths-are-common-nasa-scientist-says
(Submitted by Ray D)

NASA tests Aberdeenshire find for life on Mars clues

Tuesday, 8 December 2009

Scientists from space agency Nasa are testing a mineral only found in one corner of Scotland to see if it can provide clues about life on Mars.

Macaulayite is only believed to exist at a quarry at the foot of Bennachie in Aberdeenshire.

Researchers think it could be the same mineral which gives the planet its red colour.

Samples have now been sent to a testing centre in California in an attempt to verify its presence.
Macaulayite was discovered by researchers from Aberdeen's Macaulay Institute in the late 1970s.

The mineral is formed in the presence of water so if it does occur on the surface of Mars it could provide proof the planet can sustain life.

It is formed from granite which has been weathered by tropical climates from before the last Ice Age.

The team which found it was led by mineralogist Jeff Wilson, who is now retired.

Dr Wilson told BBC Scotland: "It is exciting because this particular mineral contains water.

"It's a very fine grain mineral and water is bound to the inner surfaces.

"There's been a lot of speculation about the occurrence of water on Mars. We don't know but it could be associated with this mineral."

The US space agency Nasa is conducting tests on Macaulayite.

Dr Janice Bishop, a Mars specialist from the Search for Extra Terrestrial Intelligence Institute, said: "All life forms as we know it require liquid water so if we can actually find periods of time or places on the planet where there was standing water then the chance of life having formed increase greatly."

Only limited data has been collected about the surface of Mars, through orbiters and probe landings.

http://news.bbc.co.uk/1/hi/scotland/north_east/8400025.stm

(Submitted by Dave McCann)

I saw UFO beam up a buffalo

By BRIAN FLYNN
Published: 02 Nov 2009

STUNNED Derek Bridges has revealed how he shot extraordinary footage which UFO experts say shows aliens beaming a BUFFALO into their spaceship.

Pensioner Derek filmed the eerie scene from his window after spotting pulsating glowing orbs hovering over a neighbouring farm late at night.

The two bright lights hover high over fields, while an animal appears to dangle below before vanishing into them.

A high-pitched screeching noise can be heard before the UFOs finally disappear into the night.

Grandfather Derek, 69, said: "I couldn't believe my eyes. I'm convinced it is the real thing."

He told how he spotted the bizarre lights over a neighbouring farm as he looked out of his window while getting ready for bed at his house near Basingstoke, Hampshire.

Quick-thinking Derek grabbed his camcorder and began filming the incident above 2,500-acre Laverstoke Park Farm in Overton village at about 10.30pm.

It has one of the country's biggest herds of water buffalo and is close to a military base used by special forces.

Derek said: "I just looked out of the window before going to bed. I wasn't sure what I was seeing at the time.

"I have a keen eye and I could see something glowing which looked dark red about half a mile away.

"I kept looking at it for about 20 minutes and then suddenly a bright white light appeared which was very powerful.

"At that point I picked up my video camera and filmed what I saw. I saw two white lights lifting up and I just kept filming. The lights were high in the sky. They couldn't have been anything on the ground.

"I did not realise at the time that something was dangling beneath but when I played it back the next day on a big screen I could see it there.

"I believe it's a UFO and this animal, which could be a bison or a horse, seems to be being beamed up.

"As far as I know, this is the first time anyone in the world has filmed animal abduction, so obviously I'm pretty chuffed."

UFO experts claim there is a long history of cattle being abducted by aliens for research, particularly in the US, sometimes being returned alive or mutilated.

There are often reports of animal carcasses found lying in fields with body parts mysteriously missing and their blood drained without the skin being spilt.

Divorced Derek told how he spoke to a farm worker who said they had found a couple of dead animals around the time the lights were filmed.

The farm - owned by 1979 Formula 1 champ Jody Scheckter - insists no cattle have gone missing

Boss Sara Whittall said: "We have never seen any aliens or UFOs around here.

"All our animals have been accounted for, so we have not had any abductions either."

But the area is a hotspot for UFO sightings.

In June last year, families in Basingstoke reported seeing a dozen glowing orange objects hovering in the sky above the town.

The "alien" fleet was captured on video, changing formation for half an hour.

Officials at nearby RAF Odiham said they could not comment at the time "for security reasons".

A trucker also reported seeing aliens just six miles from the farm in August 2007.

The footage has now been screened at a conference of UFO hunters in Scarborough.

Expert Nick Pope, who used to run the British Government's UFO Project, said the latest footage needed urgent investigation by the authorities.

He added: "If this footage is genuine, it could be highly significant."

UFO hunter Kenneth Parsons of the British Earth and Aerial Mysteries Society said he was convinced it was the first ever footage showing aliens abducting cattle.

He added: "This footage is like the holy grail. This is the first time anything like this has been filmed so clearly.

"There are no street lamps or pylons where the footage was filmed, just fields, and it is usually pitch black and silent at night, so there is no simple alternative explanation.

"We are very excited."

Derek told how he looked out of his window the next evening to see if the lights came back - and saw three helicopters flying around the field as if searching the site.

The Ministry of Defence yesterday declined to comment on the incident, saying only: "The MoD examines UFO reports solely to establish whether UK airspace may have been compromised by hostile or unauthorised military activity.

"Unless there is evidence of a potential threat, there is no attempt to identify the nature of each sighting reported."

Meanwhile UFO experts are being urged to investigate another case of aliens playing Cattlestar Galactica to steal cows.

A US cattle rancher is blaming extra-terrestrials after finding a mutilated cow with its internal organs removed on his land.

Mike Duran claims ET abducted his animal and made a surgical study of the beast before abandoning its carcass.

The cow was found with its udders and reproductive organs removed in Las Animas County, Colorado, in March.

And Duran says it happened after he spotted strange lights hovering in the skies above his ranch. "They were like a round circle in the air," he said. "I've watched them and they just disappear."

See video at: http://www.thesun.co.uk/sol/homepage/news/2708680/I-saw-UFO-beam-up-a-buffalo.html#ixzz0VtYslxPw

Argentina: Cow Abducted by Flying Saucer?

Source: http://www.rosario3.com/ and Grupo G.A.B.I.E.
Date: October 8, 2009

Argentina: Cow Abducted by a Flying Saucer?

A couple traveling along the river in the area north of Rosario claimed having seen an animal being abducted by a flying saucer. "Later, the both vanished," they said.

The likelyhood that cows could fly was always relegated to the province of the impossible. But to Sergio and Laura, this changed last Monday afternoon, when they traveled along the coast near Puerto Gaboto, and believed that they saw a cow in the sky, abducted by a UFO.

The couple told the story to journalist Guillermo Brasca in a report transmitted by the Telenoche program on Channel 3. They provided photos which are not entirely clear, but which show the alleged UFO and what would appear to be a cow in flight.

"We went to have some mate with the kids, we were looking at the island and we were surprised to see some strange white thing flying. It was large. We made a close up with the camera and it was a cow flying, and above it, there was something like a flying saucer suspended in the air (some of the photos accompany the report). It wasn't a helicopter or an airplane," said Laura. The woman added: "It seemed as if the cow was being sucked up by the flying saucer. Then they both vanished. I want to believe that's what it was. To me, it was a UFO. I experienced it."

Photos and video at: http://www.rosario3.com/noticias/enserio/noticias.aspx?idNot=58593

(Translation (c) 2009, S. Corrales, IHU. Special thanks to Grupo G.A.B.I.E)

Is our universe fine-tuned for life?

02 August 2008 by Michael Brooks

DON'T take our starry skies for granted. If you were unlucky enough to be living in some other universe, you might have nothing to stare at but black holes.

At least, that's the view of a new study that examines the nature of other universes that might support life and suggests that our cosmic habitat is nothing special after all - wondrously starry skies apart.

The idea that certain aspects of our universe make it uniquely suited to life has never been properly tested, says Fred Adams of the University of Michigan in Ann Arbor. "You hear people say our universe is fine-tuned for life, that stars are rare and couldn't form if certain things were different," he says. "The truth is, no one has done the calculations." Adams has now rectified that situation and found that it is not unusual for stars to form that can support life.

Claims of fine-tuning have generally been based on what happens when you vary a single characteristic of the universe, say the strength of gravity, while holding all others constant. That, says Adams, is too artificial a scenario to tell you anything about whether there are other universes that can support life. "The right way to do the problem is to start from scratch," he says. "You have to turn all the knobs and find out what happens."

To do this, Adams started with a simple definition of a star: a massive body held together by its own gravity that is stable, long-lived and generates energy through nuclear processes. Just three constants are involved in the formation of such stars. One is the gravitational constant. The second is alpha, the fine structure constant that determines the strength of interactions between radiation and matter. The third is a composite of constants that determines the reaction rates of nuclear processes.

Adams selected a range of possible values for each of these constants, then put them into a computer model that created a multitude of universes, or a virtual "multiverse". Each universe within the multiverse used different values for the three constants and was subject to slightly different laws of physics.

About a quarter of the resulting universes turned out to be populated by energy-generating stars. "You can change alpha or the gravitational constant by a factor of 100 and stars still form," Adams says, suggesting that stars can exist in universes in which at least some fundamental constants are wildly different than in our universe.

And though some universes were filled with things we might not usually think of as stars - radiating black holes or bodies formed of dark matter - they all gave out enough energy to power some form of life, and lasted long enough for life to evolve.

That may not necessarily be life as we know it, however. Since the simulations didn't rely on the stars producing carbon, Adams points out that very different life forms to ours might be better suited to some of the universes. Because life depends on chemistry, and chemistry depends on alpha, varying alpha changes the nature of life. "You have no idea what life would be like in a universe with different constants," Adams says.

Adams reckons his results, which will be published in the Journal of Cosmology and Astroparticle Physics, suggest that the "specialness" of our universe could well be an illusion. And this is only the very beginning of what can be probed to undermine the idea that our universe is fine-tuned for life. There are plenty more constants and processes that can be tinkered with, he says.

Adams's approach is "extremely interesting", says Michael Murphy of Swinburne University of Technology in Melbourne, Australia. "I've long had a suspicion that this talk of fine-tuning needs constant questioning and re-examination," he says. "It's sometimes hard to recognise that living somewhere else in a different way might be just as easy."

Sean Carroll of the California Institute of Technology in Pasadena is also impressed, and intrigued by the idea of unusual life forms that, say, feed off black holes. "I don't know what it would look like or how it would work, but black holes radiate, just like stars do. Why couldn't you have life arise in the 'atmosphere' of a gently radiating black hole?" he wonders.

http://www.newscientist.com/article/mg19926673.900

'Alien' lifeform wakened from 120,000 year Arctic slumber

[Why am I reminded of the Doctor Who story "The Seeds of Doom"? - Ed]

Meddling boffins refuse to heed sci-fi common sense

By Lewis Page • Get more from this author
Posted in Biology, 15th June 2009 09:52 GMT

American scientists, showing the reckless disregard for the warnings implicit in quality science fiction that is so regrettably common in the boffinry community, have revived an ancient lifeform which has been slumbering beneath the Arctic ice pack for 120,000 years. To add insult to injury, the scientists believe that their laboratory revenant may be related to indestructible super-aliens yet to be discovered on extraterrestrial iceworlds.

The creature in question is named Herminiimonas glaciei, and was revived from its aeons-long sleep by Dr Jennifer Loveland-Curtze and her colleagues from Pennsylvania State University. The purplish-brown, blobby entity was "coaxed back to life with great patience", according to Penn Uni.

The thinking is that if life can survive millennia of terrible cold beneath a glacier here on Earth, it might do so on other planets - perhaps here in the solar system, under the Martian or possible lunar icecaps.

"These extremely cold environments are the best analogues of possible extraterrestrial habitats", says Loveland-Curtze.

"The exceptionally low temperatures can preserve cells and nucleic acids for even millions of years... studying these bacteria can provide insights into how cells can survive and even grow under extremely harsh conditions, such as temperatures down to -56˚C, little oxygen, low nutrients, high pressure and limited space."

Loveland-Curtze believes that study of H Glacei in the lab can be done safely, as it is a micro-organism, rather than a huge, ravening blobomination type of affair. In fact, it's uncommonly small and puny even for a bacterium - 10 to 50 times smaller even than the well-known E Coli, and correspondingly more capable of worming its way in where it isn't wanted.

Loveland-Curtze assures us that H Glacei isn't a deadly pathogen like E Coli, however. Though she does sound a note of caution:

"It can pass through a 0.2 micron filter, which is the filter pore size commonly used in sterilization of fluids in laboratories and hospitals," she warns.

"If there are other ultra-small bacteria that are pathogens, then they could be present in solutions presumed to be sterile. In a clear solution very tiny cells might grow but not create the density sufficient to make the solution cloudy".

In summary, then, we're looking at an ancient lifeform - albeit tiny - recently wakened by meddling scientists from its hundred-thousand-year sleep beneath the polar icecap. It's capable of surviving, perhaps, in the most hostile alien interplanetary environments known to man. It can evade mankind's toughest lab sterilisation precautions.

Meanwhile humanity may be nearing its first attempt at a manned mission to Mars.

Coincidence? Or have the glacial supermicrobes, having long ago seeded Earth, merely been waiting for a vector species to arise and carry them onward to Mars for the next stage in their campaign of interplanetary conquest?

http://www.theregister.co.uk/2009/06/15/slumbering_arctic_alien/

Long odds on space viruses seeding life

01 June 2009 by Anil Ananthaswamy

LIFE on Earth is unlikely to have come from space, says a new study on viruses. If life is ever found on another planet, however, the findings could help us judge whether it arrived from space or not.

Panspermia is the idea that life was seeded by extraterrestrial microbes in the form of hardy bacterial spores that hitched a ride on a space rock and landed on Earth. Jaana Bamford of the University of Jyväskylä in Finland and her colleagues say the key to testing this theory lies with viruses, which are thought to be tied to key steps in the evolution of complex life on Earth.

To find the likelihood of viruses stowing away in spores, the team induced a colony of bacteria hosting the Bam35 virus to form spores. Of the 83 spores that were revived to create new bacterial colonies, only 23 contained the virus (International Journal of Astrobiology, DOI: 10.1017/s1473550409004479).

This result suggests that, whatever the odds of a spore-laden meteoroid going from one planet to another, the odds of viruses hitchhiking within the bacterial spores are much longer, says team member Matti Jalasvuori.

Even if the odd virus did come along from space, it does not explain the huge diversity of viruses on Earth. Unlike cellular organisms, which are all thought to have had one ancestor, viruses are descended from more than one ancestral strain, so it is unlikely that enough virus-laden meteorites landed to seed the "virosphere" we know today. It also makes it unlikely that life on Earth itself came from space. "If life on Earth was because of panspermia, we would probably see a less diverse virosphere," says Jalasvuori.

Even if the odd virus did come from space, it does not explain the huge diversity on Earth
If we find life elsewhere, he adds, the absence of a diverse virosphere could suggest that life on Mars, say, might have originated in panspermia.

Tom Ray, an ecologist at the University of Oklahoma in Norman says the arguments are "plausible, not definitive". He believes that viral complexity on Earth could have evolved however viruses originated. "If viruses quickly emerge after the appearance - either by local origin or panspermia - of cellular life, it would probably be difficult to distinguish between the two cases billions of years later."

http://www.newscientist.com/article/mg20227104.100-long-odds-on-viruses-raining-from-space.html

Rancher blames aliens for cattle mutilations

A rancher in southern Colorado has an out of this world theory for what killed one of his cows. "We have other life out there and I think that's what it is," Mike Duran said.

Duran says he's noticed strange lights flying overhead and he believes aliens may be to blame for mutilating one of his cows. "Like a round circle in the air," Duran said. "I've watched them and then they just disappear."

His ranch is near the town of Weston, which is about 20 miles west of Trinidad. Duran says his cow was found dead with her udders and reproductive organs missing. He says there were no tracks near the body.

The cow was last seen alive on Friday and found dead on Sunday. He believes aliens abducted the cow, carved it up and dropped it back by the river.

Duran claims the same thing happened in the same field in 1995. "It's just a shock that it's happened again," he said.

He's reported both incidents to the Las Animas County Sheriff's Office, but investigators have not been able to solve either case. "It's one of those unsolved mysteries, I guess," he said.

http://arbroath.blogspot.com/2009/03/rancher-blames-aliens-for-cattle.html

Dalek found in overgrown pond

Volunteers clearing up a pond pulled out branches, weeds - and a dalek.

Workers believe it may have been in the pond since being dumped during filming near Beaulieu, Hants, in the '70s, reports The Sun.

Marc Oakland, 42, said: "I'd just shifted a tree branch with my foot when I noticed something dark and round slowly coming up to the surface. I got the shock of my life when a Dalek head bobbed up in front of me.

"It was covered in mould and weed, and had quite a bit of damage. One of the dome lights was smashed, but the eye-stalk was intact."

Former Doctor Jon Pertwee made a number of episodes on location in Hampshire during the 1970s. The BBC also took Daleks there for filming in the 1980s when Colin Baker was Timelord.

Pond warden Tony Brown, 70, said: "We've dredged up everything from shopping trolleys to toys and bicycles. But this is the first time a Dalek's appeared.

"We've all agreed it best to keep the pond's exact location under wraps. The last thing we want is sci-fi fans descending on the pond frantically searching for other Dalek parts."

http://www.ananova.com/news/story/sm_3223221.html?menu=news.quirkies

See also: http://www.metro.co.uk/news/article.html?Dalek_pulled_from_murky_pond&in_article_id=567147&in_page_id=34

Life Forms May Have Evolved In Ancient Hot Springs On Mars

ScienceDaily (Feb. 21, 2009) — Data from the Mars Reconnaissance Orbiter (MRO) suggest the discovery of ancient springs in the Vernal Crater, sites where life forms may have evolved on Mars, according to a new report.

Hot springs have great astrobiological significance, as the closest relatives of many of the most ancient organisms on Earth can thrive in and around hydrothermal springs. If life forms have ever been present on Mars, hot spring deposits would be ideal locations to search for physical or chemical evidence of these organisms and could be target areas for future exploratory missions.

Carlton C. Allen and Dorothy Z. Oehler, from the Astromaterials Research and Exploration Science Directorate at the NASA Johnson Space Center, Houston, Texas, propose that new image data from the High Resolution Imaging Science Experiment (HiRISE) on MRO depict structures in Vernal Crater that appear to have arisen as part of a major area of ancient spring activity. The data suggest that the southern part of Vernal Crater has experienced episodes of water flow from underground to the surface and may be a site where martian life could have developed.

"Hot spring deposits are key target areas for future Mars missions," says Sherry L. Cady, PhD, Editor of Astrobiology and Associate Professor in the Department of Geology at Portland State University.

"Such deposits on Earth preserve evidence of the fossilized remains of the microbial communities that inhabited the hot springs over a wide range of spatial scales. The potential to find key evidence indicative of life––biofabrics, microbial remains, chemical fossils in minerals––is high when sedimentary deposits form from hydrothermal fluids. Hot spring fluids are typically laden with dissolved mineral ions that, when they precipitate out and create the hydrothermal deposit, enhance fossilization of all types of biosignatures."

-----

Journal reference:

Carlton C. Allen and Dorothy Z. Oehler. A Case for Ancient Springs in Arabia Terra, Mars. Astrobiology, 2008; 8 (6): 1093 DOI: 10.1089/ast.2008.0239

Adapted from materials provided by Mary Ann Liebert, Inc./Genetic Engineering News, via EurekAlert!, a service of AAAS.

http://www.sciencedaily.com/releases/2009/02/090212112829.htm

Alien life 'may exist among us'

By James Morgan
Science reporter, BBC News, Chicago

Never mind Mars, alien life may be thriving right here on Earth, a major science conference has heard.

Our planet may harbour forms of "weird life" unrelated to life as we know it, according to Professor Paul Davies, a physicist at Arizona State University.

This "shadow life" may be hidden in toxic arsenic lakes or in boiling deep sea hydrothermal vents, he says.

He has called on scientists to launch a "mission to Earth" by trawling hostile environments for signs of bio-activity.

Weird life could even be living among us, in forms which we don't yet recognise, he told the American Association for the Advancement of Science (AAAS) meeting in Chicago.

"We don't have to go to other planets to find weird life.

"It could be right in front of our noses - or even in our noses," said the physicist.

"It is entirely reasonable to expect we will find a shadow biosphere here on Earth.

"But nobody has actually taken the trouble to look.

"The question is why? The cost is not expensive - it would be a fraction of the money we spend searching for extraterrestrial life."

'Second genesis'
Professor Davies was one of the speakers at a symposium exploring the possibility that life has evolved on Earth more than once.

The descendants of this "second genesis" may have survived until today in a "shadow biosphere" which is beyond our radar because its inhabitants have biochemistry so different from our own.

"All our microscopes are customised for life as we know it - so it's no surprise that we haven't found microbes with different biochemistry," said Professor Davies.

"We don't quite know how weird life would look. It's as wide as the imagination and that's why it's really hard to look for."

If it exists, weird life could be based on DNA and RNA - but with a slightly different genetic code or different amino acids.

At the other end of the spectrum, we could find creatures which have more drastic differences.

"Maybe one of the elements life uses - carbon, hydrogen, oxygen, nitrogen, phosphorus - could be replaced by something else," said Professor Davies.

"When I say that, everyone immediately thinks of silicon life - because of Star Trek. But I'm not talking about anything that drastic.

"For example, most of the jobs that can be done by phosphorus can be done by arsenic."

Arsenic may be poisonous to humans, but it has chemical properties which might make it ideal in a microbe's machinery, he said.

'Mission to Earth'
So how do we go about hunting for something we have never seen before?

"There are two possibilities," said Prof Davies, Director of the BEYOND Center for Fundamental Concepts in Science.

"One is that weird life is ecologically isolated, in niches beyond the reach of mankind."

In this case, we must begin trawling the world's most inhospitable environments - deserts, salt lakes, and areas of high pressure, temperature or UV radiation.

"We could have a 'mission to Earth'. There's a big long list of places we could be looking," observed Professor Davies.

"For example, if we are looking for arsenic life, we could head for environments which are both arsenic rich and phosphorus poor - such as deep ocean vents.

"There is also a heavily contaminated lake in California which is arsenic rich - Mono Lake - and we do find microbes in there which get their energy from arsenic.

"But they don't actually incorporate the arsenic into themselves. They spit it back out again. They smoke but they don't inhale."

On the other hand, it could be that "weird life" is actually all around us - intermingled with carbon based life.

"In that case it's going to be really hard to detect - you have to find some way of filtering everything else out."

This laborious process has been used to search for unknown organisms in seawater - by painstakingly filtering everything else away.

If we did discover something unprecedented, "we'd all start arguing" said Professor Davies, a theoretical physicist.

"The question would be whether this life was truly different, or whether there was a common precursor a deep branch on the main tree of life.

"Also, how do we know we are dealing with separate Earth genesis and not a Mars genesis?

"We know rocks do get traded between the two planets, and life could hitch a ride.

"Personally, I'm only interested in establishing whether life happened more than once. If we find it has happened twice from scratch then its going to have happened all around the universe.

"It's going to be teeming with life and there's a very good chance we are not alone."

Life in the lab
Another way to determine what alternative life might look like is to try to invent it ourselves.

If we can create new molecules which can behave in life-like way, we may then go out and look for these in the environment, says Professor Steven Benner, of the University of Florida.

His team have created perhaps the closest yet to a man-made alternative form of life.

"We are announcing the first example of an artificial synthetic chemical system capable of Darwinian evolution," he told the conference.

"Is it alive? Well, I can tell you that it is not self-sustaining.

"You have to have a graduate student stand there and feed it from time to time, but it is evolving."

The molecule is essentially a modified version of our own DNA double helix - but with six "letters" in its genetic alphabet, instead of four.

These nucleotides pair up in strands, which can replicate, though only with the help of polymerase enzymes and heat.

"Sometimes mistakes are made in pairing and these mistakes are maintained in the next generation - it is evolving," said Prof Brenner.

"The next step is to apply natural selection to it, to see if it can evolve under selective pressure.

"The accepted definition of life is a molecule capable of Darwinian evolution, so we are trying to put together molecules that are capable of doing it."

But he questioned whether our definition of "living" is perhaps too "Earth-centric".

"Remember - just because you are a chemical system which is self-sustaining and capable of Darwinian evolution, that doesn't mean that is the universal definition of life," he said.

http://news.bbc.co.uk/1/hi/sci/tech/7893414.stm