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eburacum Papo-Furado
Great Old One Joined: 26 Aug 2005 Total posts: 1587 Gender: Unknown |
 Posted: 26-12-2011 17:53 Post subject: |
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| The Grauniad wrote: |
An alternative approach would be to send tens of thousands of amateur enthusiasts images over the internet for examination, though this could lead to disagreements over what constituted an unusual, and potentially alien, feature. |
That's for sure. We tried interpreting some images here on the FT forum; some people could see all sorts of artificial structures in images that other people could see nothing in. Asking 'amateur enthusiasts' to look for artificial structures is a strategy that could have its own peculiar difficulties. |
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| rynner2 What a Cad!
Great Old One Joined: 13 Dec 2008 Total posts: 21365 Location: Under the moon Gender: Male |
| Posted: 26-12-2011 18:10 Post subject: |
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| eburacum wrote: | | Asking 'amateur enthusiasts' to look for artificial structures is a strategy that could have its own peculiar difficulties. |
Presumably they're thinking of doing it on the lines of http://zoo1.galaxyzoo.org/ and its successors. With a big enough set of responses, only those flagged up by a significant fraction of the responses would be looked at, since that indicates something that looks odd to a number of people, and not just to a few isolated loonies (to coin a phrase!  ). |
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| rynner2 What a Cad!
Great Old One Joined: 13 Dec 2008 Total posts: 21365 Location: Under the moon Gender: Male |
| Posted: 30-03-2012 08:24 Post subject: |
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Cassini spacecraft captures Saturn moon geyser images
By Paul Rincon, Science editor, BBC News website
The Cassini spacecraft has captured striking images from flying by three moons of Saturn, including new pictures of Enceladus's gushing geysers.
Cassini made its lowest pass yet over the south pole of Enceladus, at at an altitude of 74km (46 miles).
This allowed it to "taste" the jets of water vapour and ice that the moon spews forth into space.
The Nasa probe also made relatively close flypasts of two other Saturnian satellites: Dione and Janus.
The observations were made over 27 and 28 March.
The encounter was primarily designed for Cassini's ion and neutral mass spectrometer instrument, which sampled the composition of Enceladus's south polar plume.
Other instruments, including the Cassini plasma spectrometer and composite infrared spectrometer, also took measurements.
Before the closest approach to Enceladus, Cassini's onboard cameras captured images of the geysers, which contain organic compounds along with the ice and vapour.
The jets erupt from cracks, or hot fissures, at the south pole known as "tiger stripes".
Several lines of evidence suggest the jets are fed by a liquid water ocean beneath Enceladus' outer icy shell.
Scientists have previously detected salts in these jets, which suggests the ocean is probably in contact with the moon's rocky core.
"Cassini has flown several times now through this spray and has tasted it. And we have found that aside from water and organic material, there is salt in the icy particles. The salinity is the same as that of Earth's oceans," said Dr Carolyn Porco, head of the imaging team on Cassini. Careful it doesn't go rusty!
As the spacecraft passed Enceladus, the cameras made a nine-frame mosaic of the surface of Enceladus's leading hemisphere.
Cassini then flew by the small moon Janus with a closest approach distance of 44,000km. The planet was in the background in some of these views.
On 28 March, the spacecraft passed Dione at roughly the same distance and captured, among other observations, a nine-frame mosaic depicting the side of the moon that faces away from Saturn.
Scientists recently presented evidence that Dione has features resembling tiger stripes and a cryovolcano, which erupts water-ammonia or methane instead of molten rock.
It is unclear whether there is current geological activity at Dione, but, if so, it is almost certainly at a lower level than on Enceladus.
The discovery that Enceladus probably harbours an ocean in contact with the rocky core makes this moon an even more important target in the search for life elsewhere in the Solar System. The rocks could furnish the ocean with the chemical ingredients thought essential for life. "The kind of ecologies Enceladus might harbour could be like those deep within our own planet," Dr Porco said in an interview with Nasa's science website.
The habitable zone on Enceladus might be comparatively easy to access by future robotic space missions. Dr Porco added: "It's erupting out into space where we can sample it. It sounds crazy but it could be snowing microbes on the surface of this little world.
"In the end, it's the most promising place I know of for an astrobiology search. We don't even need to go scratching around on the surface. We can fly through the plume and sample it. Or we can land on the surface, look up and stick our tongues out." 
The source of Enceladus's heat appears to be Saturn itself. The moon moves around Saturn in a distorted, oval-shaped orbit rather than a circular one.
This causes it to be pulled and squeezed by Saturn's gravity, inducing the heat that enables geological activity on the icy moon.
http://www.bbc.co.uk/news/science-environment-17550834 |
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| rynner2 What a Cad!
Great Old One Joined: 13 Dec 2008 Total posts: 21365 Location: Under the moon Gender: Male |
| Posted: 31-03-2012 11:16 Post subject: |
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Comets linked to beginnings of life
John von Radowitz Wednesday 28 March 2012
Shock waves from comets bombarding the Earth may have helped to build proteins and set the stage for life, scientists have learned.
Comets, giant snowballs of ice and dust, are known to have carried organic chemicals and water to the early Earth.
But just what caused life to spring out of nowhere on a barren and desolate planet billions of years ago remains a mystery.
Now scientists may have part of the answer. Laboratory experiments have shown that amino acids - organic molecules that are the building blocks of proteins - would have survived violent comet impacts.
What is more, the shock of a large comet impact would have provided the energy needed to start bonding amino acids together to make proteins.
Proteins provide the raw material that allows all living things, from microbes to humans, to exist and function.
Their creation by comets may explain how life appeared so quickly at the end of a period 3.8 billion years ago called the "late heavy bombardment". During this turbulent time the Earth was showered by both comets and rocky asteroids, leaving crater scars that are still seen on the Moon.
Dr Jennifer Blank, who led the US scientists from the Nasa/Ames Research Centre in Moffett Field, California, said: "Our research shows that the building blocks of life could, indeed, have remained intact despite the tremendous shock wave and other violent conditions in a comet impact.
"Comets really would have been the ideal packages for delivering ingredients for the chemical evolution thought to have resulted in life. We like the comet delivery scenario because it includes all of the ingredients for life - amino acids, water and energy."
Dr Blank described the experiments at the annual meeting of the American Chemical Society in San Diego, California.
Her team set out to simulate conditions that existed when Earth was repeatedly struck by amino acid-carrying comets, some of which were 10 miles or more in diameter.
One study used powerful gas guns to fire supersonic blasts of gas at capsules filled with amino acids, water and other materials.
Despite the heat and shock of the simulated collisions the amino acids did not break down. Instead, they began forming the chain-like "peptide bonds" that link amino acids together to make proteins.
Intense pressure from the impact offset the intense heat and supplied the energy needed to create the peptides.
Other experiments used computer models to simulate conditions as comets ploughed into the Earth's atmosphere.
Both comets and asteroids may have brought multiple deliveries of the "seedlings of life" to Earth, said Dr Blank.
PA
http://www.independent.co.uk/news/science/comets-linked-to-beginnings-of-life-7593751.html |
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| ramonmercado Psycho Punk
Joined: 19 Aug 2003 Total posts: 17933 Location: Dublin Gender: Male |
| Posted: 30-09-2012 13:54 Post subject: |
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Vid, images and full text at link.
| Quote: | Slow-moving rocks better odds that life crashed to Earth from space
September 24th, 2012 in Space & Earth / Astronomy
(Phys.org)—Microorganisms that crashed to Earth embedded in the fragments of distant planets might have been the sprouts of life on this one, according to new research from Princeton University, the University of Arizona and the Centro de Astrobiología (CAB) in Spain.
The researchers report in the journal Astrobiology that under certain conditions there is a high probability that life came to Earth—or spread from Earth to other planets—during the solar system's infancy when Earth and its planetary neighbors orbiting other stars would have been close enough to each other to exchange lots of solid material. The work will be presented at the 2012 European Planetary Science Congress on Sept. 25.
The findings provide the strongest support yet for "lithopanspermia," the idea that basic life forms are distributed throughout the universe via meteorite-like planetary fragments cast forth by disruptions such as volcanic eruptions and collisions with other matter. Eventually, another planetary system's gravity traps these roaming rocks, which can result in a mingling that transfers any living cargo.
Previous research on this possible phenomenon suggests that the speed with which solid matter hurtles through the cosmos makes the chances of being snagged by another object highly unlikely. But the Princeton, Arizona and CAB researchers reconsidered lithopanspermia under a low-velocity process called weak transfer wherein solid materials meander out of the orbit of one large object and happen into the orbit of another. In this case, the researchers factored in velocities 50 times slower than previous estimates, or about 100 meters per second.
"Slow-moving rocks better odds that life crashed to Earth from space." September 24th, 2012. http://phys.org/news/2012-09-slow-moving-odds-life-earth-space.html |
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| ramonmercado Psycho Punk
Joined: 19 Aug 2003 Total posts: 17933 Location: Dublin Gender: Male |
| Posted: 09-12-2012 00:04 Post subject: |
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Update on the Drake Equation.
| Quote: | At last, how many alien civilizations are there?
December 3rd, 2012 in Space & Earth / Astronomy
Frank Drake writes out his formula for estimating alien life in the galaxy, the Drake Equation.
During the space age, 1961 was a special year: the Russian cosmonaut Yuri Gagarin became the first man to orbit Earth, while the American astronomer Frank Drake developed the now famous Drake Equation. This equation estimates the number of detectable extraterrestrial civilizations in our Milky Way galaxy, supposing our present electromagnetic detection methods. The Drake equation states:
N = Ns x fp x ne x fl x fi x fc x fL
N = number of alien civilizations in the Milky Way
Ns = estimated number of stars in the Milky Way;
fp = fraction or percentage of these stars with planets on its orbits;
ne = average number of these planets with potential to host life as we know it;
fl = percentage of these planets that actually develop life;
fi = percentage of these planets that actually develop intelligence on human level;
fc = percentage of these civilizations that actually develop electromagnetic radiation emitting technologies;
fL = percentage of these civilizations that keep emitting electromagnetic signals to space. This factor is extremely dependent on the lifetime a civilization remains electromagnetic communicative.
Looking to the Drake equation factors, it is obvious that none can be precisely determined by modern science. More than that, as we move from the left to right in the equation, estimating each factor becomes more controversial. The later terms are highly speculative, and the values one may attribute to each of them might tell more about a person's beliefs than about scientific facts.
Gaussian or bell curve showing the probability of finding the nearest extra terrestrial civilization from Earth. Credit: Maccone (2010)
But the Drake equation must not be evaluated only by the numerical values it produces. Some say the Drake equation is a way to organize our ignorance. By exposing the extraterrestrial intelligence hypothesis mathematically, we limit the real possibilities to each term and approach the final answer: how many alien civilizations are there?
The L term is considered the most important one in Drake equation. We have no idea how long a technological civilization can last. Even if only one extraterrestrial civilization lasts for billions of years, or becomes immortal, the L factor would be enough to reduce Drake's equation to N = L. Actually, Frank Drake recognizes this in his license plate: " NEQLSL "
Among dozens of papers written about the Drake Equation, some have suggested new considerations for the formula. One such paper stands out for adding well-established probabilistic principles from statistics. In 2010, the Italian astronomer Claudio Maccone published in the journal Acta Astronautica the Statistical Drake Equation (SDE). It is mathematically more complex and robust than the Classical Drake Equation (CDE).
The SDE is based on the Central Limit Theorem, which states that given the enough number of independent random variables with finite mean and variance, those variables will be normally distributed as represented by a Gaussian or bell curve in a plot. In this way, each of the seven factors of the Drake Equation become independent positive random variables. In his paper, Maccone tested his SDE using values usually accepted by the SETI community, and the results may be good news for the "alien hunters".
Although the numerical results were not his objective, Maccone estimated with his SDE that our galaxy may harbor 4,590 extraterrestrial civilizations. Assuming the same values for each term the Classical Drake Equation estimates only 3,500. So the SDE adds more than 1,000 civilizations to the previous estimate.
Another SDE advantage is to incorporate the standard variation concept, which shows how much variation exists from the average value. In this case the standard variation concept is pretty high: 11,195. In other words, besides human society, zero to 15,785 advanced technological societies could exist in the Milky Way.
If those galactic societies were equally spaced, they could be at an average distance of 28,845 light-years apart. That's too far to have a dialogue with them, even through electromagnetic radiation traveling in the speed of light. So, even with such a potentially high number of advanced civilizations, interstellar communication would still be a major technological challenge.
Still, according to SDE, the average distance we should expect to find any alien intelligent life form may be 2,670 light-years from Earth. There is a 75% chance we could find ET between 1,361 and 3,979 light-years away.
500 light-years away, the chance of detecting any signal from an advanced civilization approaches zero. And that is exactly the range in which our present technology is searching for extraterrestrial radio signals. So, the "Great Silence" detected by our radio telescopes is not discouraging at all.
Our signals just need to travel a little farther – at least 900 light years more – before they have a high chance of coming across an advanced alien civilization.
Source: Astrobio.net
"At last, how many alien civilizations are there?." December 3rd, 2012. http://phys.org/news/2012-12-alien-civilizations.html |
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| ramonmercado Psycho Punk
Joined: 19 Aug 2003 Total posts: 17933 Location: Dublin Gender: Male |
| Posted: 19-01-2013 20:19 Post subject: |
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| Quote: | Rock solid proof of alien life? Scientists claim fossilized algae inside meteorite
http://rt.com/news/meteorite-life-report-mars-310/
An example of a supposedly fossilized diatom (Image from www.journalofcosmology.com)
Fossilized algae recently discovered inside a Sri Lankan meteorite could finally prove the existence of extra-terrestrial life, claim the authors of the new paper.
In a recently published article in the Journal of Cosmology titled “Fossil Diatoms in a New Carbonaceous Meteorite”, scientists from the UK and Sri Lanka claim to have found fossilized algae in a meteorite.
The paper alleges that “microscopic fossilized diatoms were found in the sample,” which fell in Sri Lanka in December last year. The finding, the work suggests is a “strong evidence to support the theory of cometary panspermia.” The theory argues that life across planets is spread by meteorites and asteroids. Panspermia suggests that life could have existed on another planet and moved to Earth.
The scientists concluded the paper by saying “the presence of structures of this kind in any extra-terrestrial setting could be construed as unequivocal proof of biology.”
Samples from the rock were collected immediately after a large meteorite disintegrated and fell in the village of Araganwila in Sri Lanka on 29 December 2012.
The scientific community, including Prof Francis Thackeray from the Institute of Human Evolution at Wits University welcomed the report as “very exciting” yet “very controversial”, as samples could have been contaminated on earth, Business Day reports.
Comparison of a Polonnaruwa meteorite structure with a well-known terrestrial diatom. (Image from www.journalofcosmology.com)
The study was conducted by a group headed by Chandra Wickramasinghe, the director of the Buckingham Centre for Astrobiology at the University of Buckingham, who was also a co-founder of Panspermia theory.
The finding however has already come under sharp criticism, with astronomers claiming that the meteorite looks more like a rock that could be found on earth as the study provides vague details of the finding.
Astronomer and lecturer Phil Plait wrote in his blog on Slate that the chemical analysis presented “doesn’t prove it’s a carbonaceous chondrite, let alone a meteorite,” and there is “no reason to trust that what they have is a meteorite.”
Plait also cited a professor of ecology and evolutionary biology Patrick Kociolek as saying that there was no sign that the diatoms illustrated in the study were “fossilized material,” and that most of them were species that represented “a clear case of contamination with freshwater.”
Speaking with HuffingtonPost, the author of the study did not deny that the meteorite his team studied contained known freshwater species from Earth. But there were also “at least half a dozen species that diatom experts have not been able to identify,” Wickramasinghe added.
He also addressed the allegations that the meteorite could be a simple rock, saying that “from all the evidence” his group possessed – which they plan to publish – they “have no doubt whatsoever” it was a meteorite.
“If only ideas that are considered orthodox are given support through award of grants or publication opportunities, it is certain that the progress of science will be stifled as it was throughout the middle ages,” Wickramasinghe said.
(Image from www.journalofcosmology.com)
(Image from www.journalofcosmology.com) |
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| rynner2 What a Cad!
Great Old One Joined: 13 Dec 2008 Total posts: 21365 Location: Under the moon Gender: Male |
| Posted: 19-01-2013 20:58 Post subject: |
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| Quote: | Speaking with HuffingtonPost, the author of the study did not deny that the meteorite his team studied contained known freshwater species from Earth. But there were also “at least half a dozen species that diatom experts have not been able to identify,” Wickramasinghe added.
He also addressed the allegations that the meteorite could be a simple rock, saying that “from all the evidence” his group possessed – which they plan to publish – they “have no doubt whatsoever” it was a meteorite.
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For heavens sake (and I mean that most sincerely!) why publish partial evidence? It only muddies the waters (already full of diatoms ) and allows doubt to creep in which will never be completely eradicated, even if science does in time come to accept this as 'evidence' of life from space.
If you have a smoking gun, we want not only pictures, but a complete technical description (including make and serial number), and an analysis of the smoke!  |
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| ramonmercado Psycho Punk
Joined: 19 Aug 2003 Total posts: 17933 Location: Dublin Gender: Male |
| Posted: 20-01-2013 01:37 Post subject: |
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| The only proof you'll accept is a monster emerging and devouring the scientists! |
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| Zilch5 Vogon Poet
Great Old One Joined: 08 Nov 2007 Total posts: 1527 Location: Western Sydney, Australia Gender: Male |
| Posted: 21-01-2013 03:13 Post subject: |
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I think a grain of salt or two might be in order here...
| Quote: | Extraterresterial Life Exists, Scientist Chandra Wickramasinghe Claims
If a group of scientists are correct, tiny fossils uncovered inside a meteorite found in Sri Lanka in December are proof of extraterrestrial life.
In a detailed paper called "Fossil Diatoms In A New Carbonaceous Meteorite" that is appearing in the Journal of Cosmology, Chandra Wickramasinghe claims to have found strong evidence that life exists throughout the universe.
An electron microscope was used to study the reported remains of a large meteorite (see image below right) that fell near the Sri Lanka village of Polonnaruwa on Dec. 29.
Wickramasinghe is the director of the Buckingham Centre for Astrobiology at the University of Buckingham in the U.K. In December, he and his colleagues found "a microstructure and morphology characteristic of a wide class of terrestrial diatoms." The group concluded that "the presence of structures of this kind in any extraterrestrial setting could be construed as unequivocal proof of biology" -- in other words, proof of life outside of planet Earth.
Wickramasinghe and the late English astronomer Sir Fred Hoyle co-developed a theory known as "panspermia," which suggests that life exists throughout the universe and is distributed by meteoroids and asteroids.
"We conclude ... that the identification of fossilised diatoms [as shown in the image below] in the Polonnaruwa meteorite is firmly established and unimpeachable. Since this meteorite is considered to be an extinct cometary fragment, the idea of microbial life carried within comets and the theory of cometary panspermia is thus vindicated," Wickramasinghe wrote in the research paper. |
http://www.huffingtonpost.com/2013/01/18/extraterresterial-life-exists-chandra-wickramasinghe_n_2500008.html?utm_hp_ref=mostpopular |
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| Anome_ Faceless Man
Great Old One Joined: 23 May 2002 Total posts: 5377 Location: Left, and to the back. Age: 45 Gender: Male |
| Posted: 21-01-2013 09:44 Post subject: |
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That might damage the diatoms.
Phil Plait has a contrary view on his Bad Astronomy blog. In fact, that's what Wickramasinghe was responding to on HuffPo.
Brief note, Chandra Wickramasinghe's brother taught me astrophysics and some other applied mathematics at uni. As I was in first year in 1986, there was some excitement about the findings from the Halley's Comet probe at the time.
The short version is that the diatoms in the photos are all freshwater species found near the site, they show no signs of being fossilised, and the rock does not look like a meteorite. |
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| eburacum Papo-Furado
Great Old One Joined: 26 Aug 2005 Total posts: 1587 Gender: Unknown |
| Posted: 22-01-2013 06:05 Post subject: |
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| Terrible science, terrible. Wickramasinge seems to be losing it. |
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| Anome_ Faceless Man
Great Old One Joined: 23 May 2002 Total posts: 5377 Location: Left, and to the back. Age: 45 Gender: Male |
| Posted: 22-01-2013 09:02 Post subject: |
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Hard to consider really, but maybe Hoyle was the less crazy one, and kept him in check...
His brother seemed relatively sane for an academic mathematician. |
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| Zilch5 Vogon Poet
Great Old One Joined: 08 Nov 2007 Total posts: 1527 Location: Western Sydney, Australia Gender: Male |
| Posted: 22-01-2013 09:23 Post subject: |
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| Anome_ wrote: | That might damage the diatoms.
Phil Plait has a contrary view on his Bad Astronomy blog. In fact, that's what Wickramasinghe was responding to on HuffPo.
Brief note, Chandra Wickramasinghe's brother taught me astrophysics and some other applied mathematics at uni. As I was in first year in 1986, there was some excitement about the findings from the Halley's Comet probe at the time.
The short version is that the diatoms in the photos are all freshwater species found near the site, they show no signs of being fossilised, and the rock does not look like a meteorite. |
Thanks - it is good to hear from someone who knows this sort of stuff. Me? I move cargo, so talking about various types of Diatoms is a bit above my station... |
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| rynner2 What a Cad!
Great Old One Joined: 13 Dec 2008 Total posts: 21365 Location: Under the moon Gender: Male |
| Posted: 22-01-2013 09:34 Post subject: |
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Hoyle and Wicky did have logic on their side however - the universe is so huge, and offers so many different environments, that the probability is very high that life (or its constituents) first evolved 'out there' somewhere, rather than on the planet we call home.
In fact, I started this thread, back in 2002, with these words:
| Quote: | | This page details lab experiments that show that amino acids, essential building blocks of proteins, and hence essential for 'life as we know it', can be created in interstellar gas clouds. |
'this page' linked to an article in Spaceflight Now which is still on the web:
http://spaceflightnow.com/news/n0205/31life/
Even if these life constituents needed to be on a planet with suitable resources in order for life to evolve further, the chances are that this happened long ago, and far away from here. After all, the Universe is about 13.7 billion years old, while the Earth is a mere 4.5 billion years old! |
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