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A Peek Into The Past

Katie Klingsporn
Telluride Daily Planet
Tue, 18 May 2010 20:30 UTC
Long before Europeans explored North American soil, a population of people flourished in the Mesa Verde area of southwestern Colorado, erecting elaborate stone structures, farming the fields and making pottery.

The Ancestral Puebloans are believed to have lived in this pocket of the southwest for more than 700 years, with a population that may have reached several thousand.

But then, somewhere around the year 1280, the population suddenly crashed.

In the world of archaeology, that much is agreed upon. What isn't so clear is how, why or what happened to the people who once inhabited Mesa Verde.

Dr. Scott Ortman, an archaeologist who lives and works in Cortez, has been pondering the issue for 15 years. And after devoting his doctoral dissertation to the subject, he has come up with a compelling theory on what happened to the people of Mesa Verde.

Ortman will be discussing it in a slideshow presentation Thursday night at the Telluride Historical Museum. The Telluride Unearthed lecture, "Archaeology, Oral Tradition and the Mesa Verde Migration," is at 6 p.m. It is $4 for members of the museum, and $6 for non-members.
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Water Not Always a Guide to Finding Life

Lindsey Doermann
Cosmos Online
Wed, 19 May 2010 03:58 UTC
Juvenile Squid
© Woods Hole Oceanographic InstitutionA juvenile squid from the Celebes Sea, between Borneo and The Philippines - one of the strange new forms of life found to be living at up to a depth of 2.8 km.
Sydney: The strategy of 'following the water' in the search for extraterrestrial life may need some tweaking, suggests a new study in the journal Astrobiology.

Put simply: there's an awful lot of places where water could exist - either on the surface of the Earth, or deep within it - yet life is largely concentrated in a small sliver of this.

Eriita Jones and Charley Lineweaver of the Australian National University in Canberra have estimated the volume of the Earth where liquid water can exist, and calculated that life inhabits as little as 12% of it.
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Info

"We Are Trailblazers," Say Mars Mission Volunteers

Alissa de Carbonnel
Agence France-Presse
Tue, 18 May 2010 20:00 UTC
Space Capsule
© AFPA participant volunteer moves inside the Mars 500 capsule in the outskirts of Moscow in April.
Moscow - The six men who enlisted to be locked up for over 500 days to simulate a mission to Mars called themselves "trailblazers" Tuesday, saying they were ready to face the strain of the isolation.

"We are trailblazers, but while this is very exciting, it brings a certain responsibility. I echo my teammates in saying we will do everything to be successful," Russian volunteer Mikhail Sinelnikov told reporters in Moscow.

The three Russians, two Europeans and one Chinese national will be sealed away for one-and-a-half years inside a 180-square-metre (1,000-square-feet) spaceship module on the outskirts of Moscow starting on June 3.

"It will be trying for all of us. We cannot see our family, we cannot see our friends, but I think it is all a glorious time in our lives," enthused Chinese participant Wang Yue, who is the youngest volunteer at age 27.

The mission will set the stage for "future generations who will actually travel frequently to Mars," said Italian-Colombian participant Diego Urbina.

The ambitious project, the first full-duration simulated flight to Mars, aims to test one of the biggest unknowns of an eventual manned mission to Mars: the psychological and physical toll on humans.
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Moon Appears to Eat Venus in New Photos


Space.com
Tue, 18 May 2010 15:21 UTC
Venus Eaten
© Joe Chan Yuen FaiVenus shines near the limb of the crescent moon during a lunar occultation on May 16, 2010 as seen by skywatcher Joe Chan Yuen Fai in Kennedy Town, Hong Kong.
Striking new photos from a skywatcher in Hong Kong show the Earth's moon appear to swallow Venus during a weekend cosmic event.

The photo above was taken by skywatcher Joe Chan Yuen Fai on Sunday, May 16 in Kennedy Town, Hong Kong, during a lunar occultation - an event in which the moon obscures a more distant star or planet.

"Seeing both Venus and moon hanging on the sky is not surprising for me, but I was excited by the phenomenon," Yuen Fai told SPACE.com in an e-mail. "The moon ate the planet Venus!"

In the photos, Venus and the crescent moon shine bright after local sunset. But as the night wears on, Venus slowly slips behind the shadowed limb - or horizon - of the moon. [More moon photos.]
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Jupiter Impact Raises Likelihood of Future Asteroid Strikes


MIT Technology Review
Tue, 18 May 2010 21:52 UTC
The strike on Jupiter last year raises the likelihood of future impacts by an order of magnitude, says a new study. But what does it mean for the Earth?

Jupiter_Impact
© MIT Technology ReviewJovian Impact
Last July, an amateur astronomer noticed that a mysterious dark bruise about the size of the Earth had suddenly appeared on the surface of Jupiter. Within hours, amateurs and professionals alike were training their instruments on the great planet to work out what had happened.

The consensus was that Jupiter had been hit by a comet or asteroid. But the surprise was that it had happened so soon after the Shoemaker-Levy comet strike observed in 1994. The worry was that this strike must have important implications for the likelihood of future impacts.

Today, Agustin Sánchez-Lavega from the University of the Basque Country in Bilbao and pals, publish their analysis of the impact and how it changes the probabilities of future impacts. They say the impactor was probably an icy object about 1 kilometre in diameter which came either from a group of main belt asteroids called Hilda asteroids or from a group of comets called the Jupiter Family.

Estimating the likelihood of such impacts is hard for a gas giant like Jupiter because the events leave no long-lasting scars on the surface. Jupiter's bruise has already faded away.
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Satellite

NASA listens one more time for Phoenix


Space Daily / UPI
Tue, 18 May 2010 21:44 UTC
Image
© NASAImage is for illustration purposes only
NASA officials say they are conducting the fourth and final series of checks this week to determine whether the Phoenix Mars Lander has resumed operations.

NASA says its Mars Odyssey orbiter will listen for a signal from Phoenix during 61 flights over the lander's site on northern Mars. The orbiter detected no transmission from the lander during earlier campaigns totaling 150 overflights in January, February and April.

In 2008, Phoenix completed its three-month mission studying martian ice, soil and atmosphere. It continued work for an additional two months before reduced sunlight caused energy to become insufficient to keep it functioning. The solar-powered robot was not designed to survive the dark and cold conditions of a martian arctic winter, NASA said, but in case it did, scientists are using Odyssey to listen for the signals Phoenix would transmit if abundant spring sunshine revived the lander.
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Telescope

Unique Eclipsing Binary Star System Discovered


Space Daily /SPX
Tue, 18 May 2010 21:40 UTC
Image
© UnknownIn this artist conception of the unique binary star NLTT 11748, the larger but less massive helium white dwarf star is partially eclipsed by the smaller but more massive normal white dwarf, which is about the size of the earth.
Astrophysicists at UC Santa Barbara are the first scientists to identify two white dwarf stars in an eclipsing binary system, allowing for the first direct radius measurement of a rare white dwarf composed of pure helium.

The results will be published in the Astrophysical Journal Letters. These observations are the first to confirm a theory about a certain type of white dwarf star.

The story began with observations by Justin Steinfadt, a UCSB physics graduate student who has been monitoring white dwarf stars as part of his Ph.D. thesis with Lars Bildsten, a professor and permanent member of UCSB's Kavli Institute for Theoretical Physics, and Steve Howell, an astronomer at the National Optical Astronomy Observatory (NOAO) in Tucson, Ariz.

Brief eclipses were discovered during observations of the star NLTT 11748 with the Faulkes Telescope North of the Las Cumbres Observatory Global Telescope (LCOGT), a UCSB-affiliated institution. NLTT 11748 is one of the few very low-mass, helium-core white dwarfs that are under careful study for their brightness variations.
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Info

New Study Reveals Link Between 'Climate Footprints' and Mass Mammal Extinction


Wiley.com
Tue, 18 May 2010 20:19 UTC
An international team of scientists have discovered that climate change played a major role in causing mass extinction of mammals in the late quaternary era, 50,000 years ago. Their study, published in Evolution, takes a new approach to this hotly debated topic by using global data modelling to build continental 'climate footprints.'

"Between 50,000 and 3,000 years before present (BP) 65% of mammal species weighing over 44kg went extinct, together with a lower proportion of small mammals," said lead author Dr David Nogues-Bravo working from the Center for Macroecology, Evolution and Climate in University of Copenhagen. "Why these species became extinct in such large numbers has been hotly debated for over a century."
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Magnify

Archaeologists Discover 2,700-Year-Old Tomb in Mexico


Guardian.co.uk
Tue, 18 May 2010 20:13 UTC
Image
© Bruce Bachand/AP PhotoWork under way inside a pyramid in Chiapa de Corzo, southern Mexico, where archaeologists found the 2,700-year-old tomb of a dignitary, the oldest such burial in Mesoamerica.
Tomb of dignitary inside pyramid in southern Mexico may be oldest such burial documented in Mesoamerica.

Archaeologists in southern Mexico have discovered the 2,700-year-old tomb of a dignitary inside a pyramid that may be the oldest such burial documented in Mesoamerica.

The tomb held a man aged about 50, who was buried with jade collars, pyrite and obsidian artefacts and ceramic vessels. Archaeologist Emiliano Gallaga said the tomb dates to between 500 and 700BC.

"We think this is one of the earliest discoveries of the use of a pyramid as a tomb, not only as a religious site or temple," Gallaga said.

Pre-Hispanic cultures built pyramids mainly as representations of the levels leading from the underworld to the sky; the highest point usually held a temple.
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Blackbox

Proof at last for Bolztmann's 140-year-old gas equation

Jacob Aron
New Scientist
Tue, 18 May 2010 14:20 UTC
It has taken 140 years, but only now do we have mathematical proof that a seminal equation describing the behaviour of gases is correct. Robert Strain and Philip Gressman at the University of Pennsylvania employed modern mathematical tools to find solutions for the Boltzmann equation, which predicts the motion of gas molecules.

The existence of molecules was still being disputed when Ludwig Boltzmann formulated his equation in 1872, but its ability to accurately predict gaseous behaviour won out over any philosophical objections. Physicists today use the equation to model gases in everything from nuclear power stations to galaxies, yet until now there was no guarantee that it would work correctly in every possible situation.

A formal proof has eluded mathematicians for so long because Boltzmann's work was ahead of his time. "All the pieces have only been in place for about five years," says Strain. The difficulty was due to a concept known as fractional derivatives.

Most of the fundamental equations in physics are differential equations, which means they describe how the rate at which one variable changes is related to another variable.
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