Recently in Planetary and Geophysics Category

BBC News: Astronomers may have found a way to identify those Sun-like stars most likely to harbour orbiting planets.

A survey of stars known to possess planets shows the vast majority to be severely depleted in lithium.

To date, scientists have detected just over 420 worlds circling other stars using a range of techniques.

Garik Israelian and colleagues tell the journal Nature that future planet hunts could be narrowed by going after stars with particular compositions.

Physics Today: The Moon is wetter than previously believed, say NASA scientists Friday, reporting the results of the Lunar CRater Observation and Sensing Satellite (LCROSS) impact probe, that slammed into lunar polar craters a month ago.

"There's water, and it is not just a little water, but significant amounts," says NASA's Anthony Colaprete, chief science investigator for the LCROSS in a press conference earlier today.

The LCROSS Centaur upper stage rocket was used to create a plume on the 9 October by smashing into the permanently shadowed region of Cabeus crater near the moon's south pole.

The resulting impact created a two-part plume of material from the bottom of the crater. The first part was a high angle plume of vapor and fine dust and the second a lower angle ejecta curtain of heavier material. This material has not seen sunlight in billions of years.

Since the impacts, the LCROSS science team has been working almost nonstop analyzing the huge amount of data the spacecraft collected. The team concentrated on data from the satellite's spectrometers, which provide the most definitive information about the presence of about 26 gallons of water.

"We are ecstatic," said Colaprete, "multiple lines of evidence show water was present in both the high angle vapor plume and the ejecta curtain created by the impact. The concentration and distribution of water and other substances requires further analysis, but it is safe to say Cabeus holds water."

The team took the known near infrared spectral signatures of water and other materials and compared them to the spectra collected by the LCROSS near infrared spectrometer of the impact.

"We were only able to match the spectra from LCROSS data when we inserted the spectra for water," said Colaprete. "No other reasonable combination of other compounds that we tried matched the observations. The possibility of contamination from the Centaur also was ruled out."

Additional confirmation came from an emission in the ultraviolet spectrum that was attributed to hydroxyl, one product from the break-up of water by sunlight. When atoms and molecules are excited, they release energy at specific wavelengths that are detected by the spectrometers. A similar process is used in neon signs. When electrified, a specific gas will produce a distinct color. The ultraviolet visible spectrometer detected hydroxyl signatures just after impact that are consistent with a water vapor cloud in sunlight.

Data from the other LCROSS instruments are being analyzed for additional clues about the state and distribution of the material at the impact site. The LCROSS science team along with colleagues are poring over the data to understand the entire impact event, from flash to crater, with the final goal being the understanding of the distribution of materials, and in particular volatiles, within the soil at the impact site.

"The full understanding of the LCROSS data may take some time. The data is that rich," said Colaprete. "Along with the water in Cabeus, there are hints of other intriguing substances. The permanently shadowed regions of the moon are truly cold traps, collecting and preserving material over billions of years."

A short trip

LCROSS was launched on the 18 June as a companion mission to the Lunar Reconnaissance Orbiter. After separating from LRO, the LCROSS spacecraft held onto the spent Centaur upper stage rocket of the launch vehicle, executed a lunar swingby and entered into a series of long looping orbits around the Earth.

After traveling approximately 113 days and nearly 9 million kilometers, the Centaur and LCROSS separated on final approach to the moon.

Traveling as fast as a speeding bullet, the Centaur impacted the lunar surface shortly after 4:31 am PDT Oct. 9 with LCROSS watching with its onboard instruments. Approximately four minutes of data was collected before the LCROSS itself impacted the lunar surface.

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USA Today: Saturn's geyser-spewing moon, Enceladus—visited by the international Cassini spacecraft on its closest flyby this week—presents planetary scientists with a geophysical locked-room mystery.

How does something buried inside an ice ball only 500 kilometers wide provide the pop to propel a plume 965 kilometers out of the moon's south pole?

"The biggest puzzle with Enceladus is where is the heat source," says Cassini scientist Linda Spilker of NASA's Jet Propulsion Laboratory, which manages the mission. "This tiny moon 'should' be frozen over like the others orbiting Saturn."

Physics Today: A Russian Rokot launcher has successfully taken off from the Plesetsk Cosmodrome with Europe's Soil Moisture and Ocean Salinity satellite on board.

SMOS, a small 658-kg satellite, will provide the first global maps of the amount of moisture held in soils and of the quantity of salts dissolved in the oceans.

"Salinity is one of the drivers for the Thermohaline Circulation, the large network of currents that steers heat exchanges within the oceans on a global scale," says Volker Liebig, ESA's director of Earth observation programs. "Its survey has long been awaited by climatologists who try to predict the long-term effects of today's climate change."

The satellite was developed by ESA in cooperation with France's CNES and Spain's Centro para el Desarrollo Tecnológico Industrial (CDTI).

Its only instrument is called the Microwave Imaging Radiometer using Aperture Synthesis (MIRAS). The device works by connecting together 69 receivers mounted on three deployable arms to measure the temperature of the reflection of Earth's surface in the microwave frequency range. This temperature is linked to both the actual temperature of the surface and its conductive characteristics, which are in turn linked to soil moisture for land surface and to water salinity for sea surface.

"The data collected by SMOS will complement measurements already performed on the ground and at sea to monitor water exchanges on a global scale," says Liebig. "Since these exchanges—most of which occur in remote areas—directly affect the weather, they are of paramount importance to meteorologists."

SMOS is the second satellite launched under ESA's Earth Explorer program to gather new environmental data. It follows the Gravity and steady-state Ocean Circulation Explorer (GOCE), which was launched in March.

Next February, Cryosat-2 will be launched to measure the thickness of the ice sheets. This will be followed in 2011 by ADM-Aeolus—designed to study atmospheric dynamics—and the Swarm mission to monitor the weakening of Earth's magnetic field. Finally in 2013 the EarthCARE mission will study clouds and aerosols.

BBC news: Drawn half a millennium ago and then swiftly forgotten, one map made us see the world as we know it today... and helped name America. But, as BBC news reporter Toby Lester discovered, the first map that outlined the continents of the world as we know them today, also named America based on a pun.

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Science: The blogosphere has been having a field day with global warming's apparent decade-long stagnation. Negotiators are working toward an international global warming agreement to be signed in Copenhagen in December, yet there hasn't been any warming for a decade. What's the point, bloggers ask?

Climate researchers are beginning to answer back in their preferred venue, the peer-reviewed literature. The pause in warming is real enough, but it's just temporary, they argue from their analyses. A natural swing in climate to the cool side has been holding greenhouse warming back, and such swings don't last forever. "In the end, global warming will prevail," says climate scientist Gavin Schmidt of NASA's Goddard Institute for Space Studies (GISS) in New York City.

Space.com: New maps reveal colorful patterns on the surfaces of Saturn's five innermost icy moons.

Some of the patterns have been seen before, but others took scientists by surprise, suggesting dynamic interactions between the moons and other particles orbiting around Saturn.

The maps of Mimas, Enceladus, Tethys, Dione, and Rhea were created from images taken by NASA's Cassini spacecraft and were presented by Paul Schenk of Houston's Lunar and Planetary Institute at a recent meeting of the American Astronomical Society.

Various: A 180-km-diameter crater in Mexico called Chicxulub was formed by an object 10 km across that caused a 100-million-megaton explosion when it hit Earth. Until now, that event had generally been believed to have caused the extinction of the dinosaurs.

A bigger crater, named Shiva, which was found by Sankar Chatterjee of Texas Tech University, is 500 km across. The explosion that caused it may have been 100 times the size of the one that created Chicxulub.

Chatterjee presented his latest findings on Shiva to the annual meeting of the Geological Society of America in Portland, Oregon, on 18 October.

The late era of the dinosaurs was a period in which volcanic activity was frequent and common, yet the dinosaurs were thriving until the two objects hit Earth.

According to the Economist:

The picture that is emerging, then, is of a strange set of coincidences. First, two of the biggest impacts in history happened within 300,000 years of each other—a geological eyeblink. Second, they coincided with one of the largest periods of vulcanicity in the past billion years. Third, one of them just happened to strike where these volcanoes were active. Or, to put it another way, what really killed the dinosaurs was a string of the most atrocious bad luck.

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Space.com: NASA scientists have finally seen in their data a debris plume created by the impact of a moon probe last week onto the Cabeus crater, at the lunar south pole.

A thermal image of the impact (credit: NASA)

The faint plume was seen in the data from the engineered crash one week after the impact of the LCROSS probe in the ultraviolet/visible and near infra-red wavelengths.

A image of a plume of debris. NASA estimates the dust went up about a mile. (credit: NASA)

"There is a clear indication of a plume of vapor and fine debris," said Anthony Colaprete, LCROSS principal investigator and project scientist.

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Various: NASA launched the Interstellar Boundary Explorer (IBEX) spacecraft last year to investigate the edges of the heliosphere—the insulating bubble the sun creates around the solar system. IBEX principal investigator David McComas talks to NPR's Ira Flatow on the first surprising results that were published by Science on Friday.

What did IBEX discover?

At the boundary of our Solar System, the interactions between solar wind particles and interstellar medium particles create Energetic Neutral Atoms (ENAs), particles with no charge that move very fast.

Some of the ENAs happen to be travel inwards through the Solar System toward Earth where IBEX can collect them. This region emits no light and so cannot be observed by conventional telescopes.

The five maps released by the group on Friday show that ENA's are not uniformly spread across the sky, which was the opposite of what was expected with the existing theoretical models of the heliosphere's behavior.

Instead there is there is an arc-shaped region in the sky that is creating a large amount of ENAs, showing up as a bright, narrow ribbon on the maps.

IBEX is also observing many more ENAs from smaller regions in the sky than researchers thought they would.

The ribbon appears to be produced by the alignment of magnetic fields outside our heliosphere. "These observations suggest that the interstellar environment has far more influence on structuring the heliosphere than anyone previously believed," says McComas on the IBEX site.

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Various: The experiment to smash part of a rocket upper stage into the Moon at high speed (as reported earlier this week) went without a hitch but did not produce a visible plume 10 kilometers high as expected.

Vincent Eke, from the University of Durham, told the Independent that the lunar surface may not have reacted as expected and stressed it was still too early to know if the mission had been a success or failure.

"If it turns out to be as dull as it looked, I'd imagine the soil just didn't respond as was hoped to being hit," said Dr Eke. "It might mean we don't get sufficient data, which would be a shame."

Researchers are now analyzing the data gathered from the event, NASA told NPR, and expect to know for certain if the impact dislodged any water in about two weeks.

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London Times Online: The Lunar Crater Observation and Sensing Satellite (LCROSS) will blast two huge chunks out of the lunar surface on Friday in order to have a closer look at what the Moon is made of.

The plume will be created by dropping the Centaur upper stage of the rocket that fired LCROSS to lunar orbit onto the surface near one of the lunar poles.

When the 2.4-tonne Centaur hits the ground, it will be traveling at 2.5km per second, and throw up a plume of debris 10km high that can be analyzed by instruments on the LCROSS spacecraft.

Various: Two earthquakes caused devastation across the Pacific earlier this week. One, based off the coast of Samoa caused a tsunami; the other, near Sumatra, was so deep that no tsunami occurred, but the loss of life on the surrounding area may be greater.

"The chances of there being a connection between these two earthquakes is extremely slim," said University of Ulster geophysicist John McCloskey, told the London Times. The 10,000 km distance between the quakes and the orientation of the tectonic plates made a causal link physically implausible, he said.

"The real danger in the coming days is that a second larger quake with a magnitude of around 8.5 could occur just off the coast of Padang," Professor McCloskey said. That could result in a huge tsunami submerging the town and surrounding coastline, which has a population of about 1.5 million.

A magnitude 6.6 event off the coast of Sumatra happened earlier today.

The tsunami earthquake

The tsunami that devastated the islands of Samoa, American Samoa, and Tonga was the result of a shallow rupture in the earth's crust on one of the most geologically active areas of the world—where the Pacific plate is plunging westward under the Australia plate at a rate of 86 mm a year.

The earthquake, which was measured as high as 8.3 on the Richter scale, occurred 190 kilometers southwest of American Samoa. The event caused one side of the fault line to push up several meters higher than the other side, according to initial estimates.

Gary Gibson, a senior seismologist at Environmental Systems and Services in Melbourne, told Australia's ABC network that the energy released in the earthquake was approximately one-thirtieth the size of the Boxing Day 2004 earthquake near the island of Sumatra, Indonesia.

Gibson also mentioned to the Sydney Morning Herald that this earthquake was unusual in that it was due to a north-east to south-west tension in the crust. "The earth [was] being stretched rather than compressed," he said.

After the earthquake, the Pacific Tsunami Warning Centre issued a tsunami warning for South Pacific nations, including New Zealand, which experienced a rise in sea level of 40 cm, but Samoa, American Samoa and Tonga were too close to the initial event to get enough warning.

"People who live in areas where tsunamis can occur are generally educated about them," said John Bellini, a geophysicist with the National Earthquake Information Center in Denver, Colorado. "If you feel an earthquake, get to high ground as fast as you can." In this case, he adds, "Five minutes was not enough time for emergency services to move into action."

Analysis of the data indicated that Hawaii was too far away for any major tide rise to occur.

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Space.com: NASA has long planned to mine water on the Moon to supply human colonies and future space exploration. Now the discovery of small amounts of water across much of the lunar surface has shifted that vision into fast-forward, with the US space agency pursuing several promising technologies.

A hydrogen reduction plant and lunar rover prospectors have already passed field tests on Hawaii's volcanic soil, and more radical microwave technology is being evaluated.

"You can make back costs fairly quickly [within a year] compared to the launch costs of just throwing tanks of water and oxygen at the moon," said Gerald Sanders, manager of NASA's InSitu Resource Utilization Project.

Still, Sanders cautioned that there are big unknowns—how much water the Moon holds, where it is, and how deep will they have to excavate to get to it.

Earth Island Journal: A recent New York Times article pointedly asked whether NASA climate scientist James Hansen still matters. The subtext to the story was, has Hansen been too vocal and too unconventional in his criticism of Washington’s response to climate change to be taken seriously?

Nell Greenberg interviews Hansen over his recent political action on combating climate change, and how he ended up in climate science in the first place.

NPR: NASA is running out of the special kind of plutonium needed to power deep space probes, worrying planetary scientists who say the US urgently needs to restart production of plutonium-238.

But it's unclear whether Congress will provide the $30 million that the administration requested earlier this year for the Department of Energy to get a new program going.

Various: New data and images from flybys of the Moon by the Cassini, the US Deep Impact spacecraft, and a NASA instrument on India's Chandrayaan-1 orbiter provide compelling evidence of traces of water on the Moon. The results were published in Science magazine.

Tentative clues for the existence of water ice on the Moon have existed for sometime. Faith Vilas, director of the Multiple Mirror Telescope in Arizona saw phyllosilicates—minerals formed through heat and water—back in 1999 when the Galileo spacecraft flew by the Moon, but until recently could not get her research accepted for publication.

Both the Clementine and Lunar Prospector spacecrafts saw some hints of hydrogen molecules some years ago. But it was new data from the Lunar Reconnaissance Orbiter, (LRO) which was discussed at a conference last week that gave hints that conditions would be ripe for water ice.

The LRO's Diviner Lunar Radiometer Experiment, which measured the temperature of the lunar surface, discovered that some of the polar craters contain some of the lowest temperatures in the solar system, even colder than the surface of Pluto. These measurement were proof that the Moon has permanently dark and extremely cold places said science team member Ashwin Vasavada from NASA's Jet Propulsion Laboratory in Pasadena, California at the conference.

Data from the LRO's Lunar Exploration Neutron Detector didn't show many neutrons inside the craters but surprisingly showed evidence of ice outside of the craters says University of Arizona astronomer William Boynton. "It actually could be better (for exploration) because getting down inside those craters is very difficult," he adds.

According to the results published in Science, concentrations in sunlit soil might average about one liter per ton of lunar material. That water doesn’t remain on the Moon, but comes and goes each lunar day.

In contrast, water molecules bound to phosphate minerals within volcanic rocks—material that formed well beneath the lunar surface—date back several billion years, says Francis McCubbin of the Carnegie Institution for Science in Washington DC A fourth, unpublished study led by McCubbin finds a surprisingly high abundance of this interior water, which may shed new light on how the Moon formed.

"It’s so startling because it’s so pervasive," said Lawrence A. Taylor of the University of Tennessee, Knoxville, a co-author of one of the papers that analyzed data from a NASA instrument aboard India’s Chandrayyaan-1 satellite. "It’s like somebody painted the globe," he told the New York Times.

Carle Pieters, of Brown University, who led the Chandrayaan-1 observation team, said: "When we say ‘water on the moon’, we are not talking about lakes, oceans or even puddles. Water on the moon means molecules of water and hydroxyl that interact with molecules of rock and dust specifically in the top millimeters of the moon’s surface," she told the London Times.

The discovery of more evidence for water on the Moon is spurring excitement over its implications for future space exploration says space.com's Leonard David.

"If ice is found we have to further explore it with landers, rovers, coring drills to assess its distribution and composition," explained Bernard Foing, the European Space Agency (ESA) project scientist for the now defunct ESA SMART-1 lunar orbiter. He is also the director of the International Lunar Exploration Working Group (ILEWG).

Following that appraisal, Foing said that the next task is to organize how ice could be partly exploited on the spot in some areas to ease the next steps of human exploration towards an international lunar base.

NASA help hold a press conference to announce the findings at 2:00pm EST earlier today.

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Space.com: Efforts to free the stuck Spirit rover on Mars have been dragging on since May. Last week a NASA official said the robot may never get free.

"We are proceeding very cautiously and exploring all reasonable options," said John Callas, NASA project manager for Spirit and its twin, Opportunity. "There is a very real possibility that Spirit may not be able to get out, and we want to give Spirit the very best chance."

Wired.com: A Texas team called Armadillo Aerospace is the first to qualify for the top prize in the Northrop Grumman Lunar Lander Challenge after flying its moonship twice in two hours to simulate a moon landing. Armadillo Aerospace is one of three teams in the hunt for the $1 million award.

The Texans saw their craft, Scorpius, easily meet the requirements for Level 2 of the challenge, which require ascending to at least 50 meters, flying horizontally, and landing on a rocky replica of the lunar surface 50 meters away then making a return flight.

Each flight, made last weekend in Caddo Mills, Texas, had to last 180 seconds. John Carmack, the legendary coder behind Doom and Quake who leads Armadillo Aerospace, said Scorpius is capable of much greater altitude.

"Our Scorpius vehicle actually has the capability to travel all the way to space," he said, adding that Armadillo plans flights to 6,000 feet soon at its base in Texas before heading to New Mexico to achieve greater heights. Fully loaded with ethanol and liquid oxygen fuel, the craft weighs about 1,900 pounds.

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The Walrus: Installed on the second floor of a small building on the summit of Arizona's Mount Graham, Guy Consolmagno is multitasking. He's checking e-mail on his laptop and listening to the Penguin Cafe Orchestra on his iPod, all the while keeping an eye on a bank of computer monitors.

One floor up, nestled in a silvery-white dome, a telescope is trained on a potato-shaped chunk of rock and ice known as Haumea, which orbits the Sun some six billion kilometers from Earth. Thin clouds have been drifting overhead since sundown, but if they dissipate, the telescope's digital camera will record changes in Haumea's brightness as it tumbles through the outer reaches of the solar system, offering Consolmagno and fellow astronomers hints about the structure and evolution of our planetary family.

All this is typical fare for a scientist. What is perhaps surprising is that Consolmagno is also a Jesuit brother, that many of his colleagues are ordained priests, and that they're scanning the heavens with the Vatican Advanced Technology Telescope or, more affectionately, the "Pope scope." The state-of-the-art facility is part of the Vatican Observatory, established behind St. Peter's Basilica in 1891 by Pope Leo XIII at least partly to show that the Roman Catholic Church was not anti-science—an allegation that has persisted since Galileo was dragged before the Inquisition for claiming that the Earth moves.

BBC News: Less than two months before the scheduled launch of Russia's flagship planetary spacecraft, officials are set to recommend a delay until 2011.

The Phobos-Grunt mission aims to land on the Martian moon Phobos to collect soil samples and return them to Earth.

Sources within the Russian space industry gave RussianSpaceWeb.com details of the likely postponement.

The Russian space agency Roscosmos is expected to announce the mission's fate within a week.

The agency's decision will be based on results of testing which the spacecraft has been undergoing since July at its assembly facility at NPO Lavochkin in Khimki, near Moscow.

A delay for Phobos-Grunt would also affect China's first Mars probe Yinghuo 1, as the two craft are due to be launched together on the same Zenit rocket.

Wired.com: When astronomers discovered COROT-7b in February, they couldn’t determine its mass because they didn’t have precise enough measurements of the velocity of its star. Now, using 70 hours of observation data from the High Accuracy Radial velocity Planet Searcher (HARPS) spectrograph, scientists from the European Southern Observatory have calculated that the exoplanet is only about five times more massive than Earth.

Combined with the planet’s known radius, which is almost twice that of Earth, the new mass measurement makes COROT-7b the first exoplanet with a known density similar to Earth’s.

Nature News: The earthquake that rocked the ancient city of L'Aquila, Italy, less than six months ago was caused by a fault not thought to be a major seismic hazard.

The Gran Sasso region near L'Aquila is criss-crossed with large, looming faults running through the mountainous terrain that their activity has created. But the first published analyses of the quake, which struck on 6 April and killed 307 people, suggest that the culprit was the Paganica fault, an undistinguished fracture in comparatively flat ground.

"It shows it is dangerous to work on the assumption that the faults associated with the largest topographic features are going to produce the largest events," says Richard Walters, who studies tectonics at the University of Oxford, UK.

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Science: The Moon isn't made of green cheese and almost certainly doesn't harbor hypothetical particles called "strangelets," an analysis of lunar soil has shown. The result undermines a possible strangelet sighting a decade ago and strengthens the case that the bizarre particles, which protesters once feared might emerge from an atom smasher and consume Earth, don't exist.

"I'm not surprised," says Frank Wilczek, a theorist at the Massachusetts Institute of Technology (MIT) in Cambridge. "It would be a great discovery to find strangelets, but the theoretical case for them is pretty shaky." Still, he says, "it's not crazy" to look for them.

The Daily Telegraph: US scientists are trying to map the complex interplay of attractive forces between planets and moons in order to reduce the amount of fuel used by spacecraft. The Genesis spacecraft used this technique in 2004 to cut its fuel load by a factor of ten.

Depicted by computer graphics, the optimal journey pathways look like strands of spaghetti that wrap around planetary bodies and snake between them.

The pathways connect sites called Lagrange points where gravitational forces balance out.

Virginia Tech's Shane Ross said: "I like to think of [these tubes] as being similar to ocean currents, but they are gravitational currents."

"If you're in a parking orbit round the Earth, and one of them intersects your trajectory, you just need enough fuel to change your velocity and now you're on a new trajectory that is free."

"It's not the same as a [gravitational] slingshot," said Ross. "Slingshots don't put you in orbit round a moon, whereas this does."

COSMOS magazine: Jupiter's gravity captured a comet in the mid-20th century, holding it in orbit as a temporary moon for 12 years.

The comet, named 147P/Kushida-Muramatsu, is the fifth body known to have been pulled by Jupiter from its orbit around the Sun.

The discovery adds to our understanding of how Jupiter interferes with objects from the "Hilda group," which are asteroids and comets with orbits related to Jupiter's orbit.

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Quasi-Hilda Comet 147P/Kushida-Muramatsu: Another long temporary satellite capture by Jupiter

Nature News: How quickly did oxygen build up in Earth's early atmosphere? An analysis using chromium isotopes trapped in ancient ocean deposits has provided an unexpected clue.

A team led by Robert Frei of the University of Copenhagen, Denmark, sampled banded iron formations—an iron-rich sedimentary rock—dating from around and in between the two main periods of intense oxygen increases. They show that oxygen snuck into surface ocean waters 2.8-2.6 billion years ago—at least 200 million years earlier than predictions based on analyses of other metal isotopes.

More surprisingly, they also claim that around 1.9 billion years ago, oxygen levels actually dipped back down to almost where they were before the Great Oxidation Event, at less than 1% of today's levels.

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The Times of India: Contrary to India's space agency ISRO's explanation that Chandrayaan-1's orbit around the Moon had been raised from 100 km to 200 km in May this year for a better view of the Moon's surface, it is now known that this was because of a miscalculation of the Moon's temperature that had led to faulty thermal protection. As stated in the Times of India:

Admitting this, T K Alex, director of the ISRO Satellite Centre in Bangalore, said, "We assumed that the temperature at 100 km above the Moon's surface would be around 75 degrees Celsius. However, it was more than 75 degrees and problems started to surface. We had to raise the orbit to 200km."

On May 19, however, ISRO said it had raised Chandrayaan's orbit to "enable further studies on orbit perturbations, gravitational field variation of the Moon and also enable imaging of the lunar surface with a wider swath."

It now transpires that heating problems on the craft had begun as early as November 25, 2008, forcing ISRO to deactivate some of the payloads—there were 11 in all.

As a result, some of the experiments could not be carried out which raised questions on whether the pre-launch thermal vacuum test done on the spacecraft at the ISRO Satellite Centre in Bangalore was adequate.

Sources at NASA headquarters told Physics Today last year that they were concerned with the documentation and test results provided by ISRO for integrating two NASA-funded experiments onto the spacecraft: M³, the Moon Mineralogy Mapper, and miniSAR, a Synthetic Aperture Radar system to search for lunar polar ice.

NYTimes.com: A $17 million energy project in California that was supposed to demonstrate the feasibility of extracting vast amounts of heat from the Earth's bedrock has been suspended indefinitely after the drilling essentially snagged on surface rock formations.

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NYTimes.com: India's national space agency said that communications with Chandrayaan-1, its first spacecraft to orbit the moon, were lost on Saturday and that its scientists were no longer controlling the orbiter.

Chandrayaan-1's mission was expected to continue for at least another year.

Related Physics Today article
Countries Race to Launch Moon Missions

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latimes.com: Scientists have discovered a planet that shouldn't probably exist.

The planet is known as a "hot Jupiter," a gas giant orbiting the star Wasp-18, about 330 light-years from Earth. The planet, Wasp-18b, is so close to the star that it completes a full orbit (its "year") in less than an Earth day, according to the research, which was published in the journal Nature.

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Space.com: Officials are hurriedly looking for ways to save fuel on NASA's $79 million lunar impactor mission after a crisis Saturday caused the spacecraft to burn more than half of its remaining propellant.

The Lunar Crater Observation and Sensing Satellite used about 140 kilograms of maneuvering fuel to maintain the probe's orientation in space Saturday, according to Dan Andrews, the mission's project manager at Ames Research Center.

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Science News: By analyzing motions recorded by hundreds of seismometers during dozens of quakes, researchers have compiled a new and improved geological model of Southern California’s crust. The resulting high-resolution model is much like a CT scan of Earth and will enable more accurate estimates of seismic hazards in the region.

Seismic vibrations travel through some types of rock more quickly and with less damping than others. Such variations have to be taken into account when pinpointing the epicenter of a quake, says Carl Tape, a seismologist at California Institute of Technology in Pasadena. In Science, Tape and his colleagues describe the enhanced model of Southern California’s crust built with data gathered by the dense network of seismic instruments in the fault-ridden region.

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WSJ.com: In a paradox of creation, new evidence suggests that devastating avalanches of cosmic debris may have fostered life on Earth, not annihilated it. If so, life on our planet may be older than scientists previously thought—and more persistent.

Science News: An oceanographic survey has discovered a 1,400-meter-tall plume rising from the seafloor off the coast of California. Water samples taken at the site, about 32 kilometers northwest of Cape Mendocino, indicate that the feature isn’t mineral-rich water spewing from a hydrothermal vent, but researchers aren’t yet sure exactly what the feature is made of.

BBC News: A Nasa space telescope has found evidence of a high-speed collision between two burgeoning planets orbiting a young star.

Astronomers say the cosmic smash-up is similar to the one that formed our Moon some four billion years ago, when a Mars-sized object crashed into Earth.

NPR: NASA is taking to the skies to encourage a new generation of scientists to study Earth.

The agency is hoping its new Student Airborne Research Program (SARP), a six-week session that includes research aboard a DC-8 flying laboratory, will get young people excited about solving problems like warming oceans, rising carbon dioxide levels, and new pollutants in the air.

The Guardian: The world's highest mountains sit near the equator because colder climates are better at eroding peaks than had previously been realized, says David Egholm of Aarhus University in Denmark in Nature .

Mountains are built by the collisions between continental plates that force land upwards between 1–10 mm per year.

In colder climates, the snowline on mountains starts lower down, and erosion takes place at lower altitudes. At cold locations far from the equator, Egholm found, erosion by snow and ice easily matched any growth due to Earth's plates crunching together.

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Science News: Saturn’s moon Titan has an environment that resembles Earth’s at the time that life first got a foothold, suggest new findings from the Cassini spacecraft.

Two close flybys have gathered fresh evidence that ammonia, most likely mixed with water ice, has recently erupted onto the surface of the moon. The likely presence of ammonia on Titan’s icy surface, combined with the abundance of methane and nitrogen in the moon’s thick atmosphere, together suggest that Titan may host a prebiotic brew, says Cassini scientist Robert Nelson of NASA’s Jet Propulsion Laboratory in Pasadena, California.

The findings were reported by Nelson 5 August in Rio de Janeiro at a meeting of the International Astronomical Union

Science: Dynamicists simulating the solar system's early days are finding that a violent reshuffling of bodies large and small may explain many of today's planetary mysteries.

Physics Today: For the first time in the history of scientific ocean drilling, scientists have successfully drilled nearly a mile beneath the ocean floor into one of the world’s most active earthquake zones.

The experiment, part of the Japanese Integrated Ocean Drilling Program (IODP), was to gather seismic data.

The deep-sea drilling vessel Chikyu used a technique called riser drilling to penetrate the upper portion of the Nankai Trough, an earthquake zone located about 36 miles southeast of Japan. The region is a subduction zone in which the Philippine Sea plate is sliding beneath the island.

One of the principle investigators, Timothy Byrne of the University of Connecticut, says that the experiment will enable scientists to measure the trough's stress magnitude and pore pressure, which "are both important to understanding earthquake processes."

"Ultimately," says Demian Saffer, a co-investigator from Pennsylvania State University,
"we plan to install long-term observatory systems in these boreholes that will allow us to continuously monitor the geologic formation during the earthquake cycle."

Physics Today: NASA's Opportunity rover has eyed an odd-shaped, dark rock on the surface of Mars—NASA scientists think it could be a meteorite.

Above is a close-up view of "Block Island," the odd-shaped, dark rock, which may be a meteorite. The rock was imaged with the navigation camera on NASA's Mars Exploration Rover Opportunity on sol 1959 (July 28, 2009). Credit: NASA/JPL-Caltech

The NASA team spotted the rock, which measures about 0.6 meters across, on July 18 in the opposite direction from which the rover was driving. Currently Opportunity has been directed to approach the rock for further analysis with the alpha particle X-ray spectrometer to get composition measurements and to confirm if indeed it is a meteorite.

SPACE.com: The Lunar Laser Ranging Experiment is the only moon investigation to continuously operate since the Apollo 11 mission.

The experiment studies the Earth-Moon system and beams the data to labs around the world, including NASA's Jet Propulsion Laboratory (JPL) in Pasadena, Calif.

Data from the ranging experiment has been used to learn—among other things—that the moon has a fluid core and is moving away from the Earth, and that Einstein's Theory of Relativity is accurate.

The instrument itself, called a lunar laser ranging reflector, was originally intended to accurately calculate the distance between the Earth and moon by measuring the round-trip time of a laser fired from Earth to a reflector on the instrument.

Science News: Michael C. Kelley, an atmospheric physicist at Cornell University, and his colleagues suggest in the July 28 Geophysical Research Letters that data gleaned from analyses of high-flying clouds formed by the space shuttle after takeoff, as well as knowledge about the speed at which shuttle exhaust wafted to polar regions, now hint that the Tunguska blast of June 1908 resulted from a comet slamming into Earth’s atmosphere.

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Science: How high is up? The US government has launched a 10-year, $38 million research project called Gravity for the Redefinition of the American Vertical Datum (GRAV-D) to answer that question in hopes of improving its management of coastal regions and reducing the damage from severe storms and rising sea levels.

The key instrument is an airborne gravimeter coupled with GPS. Placed inside the National Oceanic and Atmospheric Administration's Cessna Citation II jet, the gravimeters will measure the acceleration of gravity at the same time that GPS instruments aboard NASA's Gravity Recovery and Climate Experiment satellite measure the plane's vertical acceleration. Thus, equipped researchers can produce large-scale regional land and sea surveys without the inconsistencies of leveling, says Vicki Childers, project manager for GRAV-D.

SPACE.com: Uranium exists on the Moon, according to new data from a Japanese spacecraft.

The findings are the first conclusive evidence for the presence of the radioactive element in lunar dirt, the researchers said. They announced the discovery recently at the 40th Lunar and Planetary Science Conference.

Scripps Oceanography News: George G. Shor Jr, professor emeritus of geophysics at Scripps Institution of Oceanography, University of California, San Diego, died 3 July at his home in La Jolla, California, from complications following several strokes. He was 86 years old.

Shor's distinguished career included helping develop the nation's consortium of research ships operated by oceanographic institutions and participating in the creation of the California Sea Grant program.

Shor was born 8 June 1923, in New York City. He received his BS degree in mechanical engineering from California Institute of Technology (Caltech) in 1944. He joined the Naval Reserve and served in World War II as an electronics officer and communications officer, with duty in the Pacific theater on a ship that transported troops. After the war, he remained in the Naval Reserve until his retirement as commander in 1983.

In the fall of 1946 he returned to Caltech for graduate work in geophysics and received an MS degree in 1948. He then worked for Seismic Explorations, Inc. (SEI), based in Houston, which had a number of crews prospecting for oil. He worked in New Mexico and west Texas, and by 1949 he led the operations of one of the company's crews.

In 1951 Shor returned to Caltech for his Ph.D. in seismology and geology. His adviser was the noted earthquake expert Charles Richter. Shor received his PhD in 1954, with a dissertation on recording blasts to reach the Mohorovicic discontinuity, the boundary layer between Earth's crust and mantle, the depth of which varies from about 3 miles beneath the ocean floor to about 25 miles beneath the continents.

In 1953 Shor began work at Scripps Institution of Oceanography as an assistant research geophysicist at the Marine Physical Laboratory, and he continued with that unit until his retirement in 1991. During his decades at Scripps, he advised many graduate students.

Shor planned and served as chief scientist on many research expeditions at sea, where he carried out studies of the structure beneath the sea floor, using refraction and reflection techniques, from explosives to air guns. His early work was in the Gulf of Alaska, a region then little known for its geologic history.

In 1960 he led the first leg of the first expedition by Scripps into the Indian Ocean, part of the International Indian Ocean Expeditions. His research continued in that region, and he became a special adviser to the Committee for Coordination of Joint Prospecting for Mineral Resources in Asian Offshore Areas (CCOP) from 1976 to 1991.

Project Mohole was established in the mid-1950s an attempt to retrieve a sample of material from Earth's mantle by drilling a hole through the Earth's crust to the Mohorovicic discontinuity, or Moho. If successful, this highly ambitious exploration of the intraterrestrial frontier would provide invaluable information on Earth's age, makeup, and internal processes. In addition, evidence drawn from the Moho could be brought to bear on the question of continental drift, which at the time was still controversial. Shor served on some of the Mohole Project's committees and scheduled several expeditions to determine geologic structure. He and his colleague Russell W. Raitt identified the best location to drill the hole, off Hawaii. The project was ended by Congress before drilling could begin.

In the 1960s Shor helped to establish the California Sea Grant program, headquartered at Scripps and involving a number of California universities. He served as its manager from 1969 to 1973. The organization founded a great many studies on marine subjects within the state.

Shor was chairman of two divisions at Scripps Institution of Oceanography. From 1968 until his 1991 retirement he served as an associate director of the institution, primarily for seagoing operations and management of the institution's fleet of research ships. He participated in the establishment of the University-National Oceanographic Laboratory System (UNOLS), which coordinates operations of the research ships operated by oceanographic institutions.

Shor was a member of the American Association for the Advancement of Science, the American Geophysical Union, the American Miscellaneous Society, the Society of Exploration Geophysicists, the Seismological Society and Sigma Xi.

He is survived by his wife of 59 years, Scripps historian Elizabeth (Betty) Noble Shor, and three children.

The family suggests donations in his memory be made to Scripps Institution of Oceanography for its valuable oceanographic research collections or to Friends of the International Center at UC San Diego for scholarships.

ScienceNOW: One fine day about 74 000 years ago, a giant volcano on Sumatra blew its top. The volcano, named Toba, may have ejected 1000 times more rock and other material than Mount St. Helens in Washington State did in 1980. In the process, it cooled the climate by at least 10 °C, causing a global famine.

But could the aftermath have been even worse? A new study in the Journal of Geophysical Research—Atmospheres puts to rest questions about whether Toba plunged Earth into a 1000-year deep freeze. Their simulations indicate that the temperature drop would last only a few decades and put to rest the claim that volcanic eruptions could have a long-term impact on the climate.

Nature: Cratons are the oldest, most stable parts of Earth's crust, and as such hold clues to Earth's early evolution.

Dewashish Upadhyay, a geochemist now at the Indian Institute of Technology in Kharagpur, analyzed the make-up of isotopes in rocks from India's Bastar craton and found that some of the rocks carry the signature of a differentiation event—the separation of materials with different geochemical properties.

This event must have taken place during the first 400 million years of Earth's history, possibly when a magma "ocean" covering the planet solidified.

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SPACE.com: The dwarf planets and other objects that litter the Kuiper belt in the far reaches of our solar system are a strange bunch, but astronomers have found what they think might be the weirdest one.

Discovered on Dec. 28, 2004 (cataloged as 2003 EL61 and nicknamed "Santa" for a time), the minor planet now known as the dwarf planet Haumea, to honor its Hawaiian discovery, is as big across as Pluto and one-third of its mass, but shaped something "like a big squashed cigar," said one of the astronomers who studies the object, Mike Brown of Caltech.

Haumea—which has a satellite moon named Namaka—is currently undergoing a series of mutual occultations and eclipses with Namaka. "Study of these events will allow us to study this system with unprecedented detail," says Brown.

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The Independent: The most powerful camera that has ever been used to survey another planet is capturing spectacular pictures of the surface of Mars to reveal a rich tapestry of geological features.

Located on board the Mars Reconnaissance Orbiter, a Nasa probe launched in 2005, the HiRise camera has already taken detailed images of the outlines of ancient extra-terrestrial seas and rivers—the first unambiguous evidence that shorelines once existed on the Red Planet.

The camera has also witnessed in high-resolution detail the moment when the warmth of the Martian spring forced puffs of dust through the thin polar caps of dry ice—solid carbon dioxide—to form weird "starburst" patterns on the surface of the planet.

"Spring on Mars is quite different from spring on Earth because Mars has not just permanent ice caps, but also seasonal polar caps of carbon dioxide," said Candice Hansen-Koharcheck, of Nasa's Jet Propulsion Laboratory in Pasadena, California.

ScienceNOW: Scientists probing the outer reaches of our solar system have hit upon an unusual phenomenon much closer to home. Instruments aboard a NASA spacecraft have detected fast-moving hydrogen atoms emanating from the Moon. The atoms, which originated as protons from the Sun, may help scientists study the lunar surface and other solar system objects in greater detail than believed possible.

Calgary Herald: It's a little-known natural wonder along Baffin Island's rugged east coast, a spectacular, 110-km-long channel lined by towering cliffs that — despite its extreme remoteness — is a mecca for base-jumping enthusiasts from around the world.

But U.S. scientists who have reconstructed a cataclysmic glacial meltdown in prehistoric Canada say Nunavut's Sam Ford Fiord is also a sentinel of danger in the age of climate change, showing just how quickly the planet's massive coastal glaciers could disappear and send global sea levels surging.

Their study, published this week in the journal Nature Geoscience, says the rapid melting of the fiord's colossal, kilometre-deep glacier about 9,500 years ago is proof that similar features found today in Greenland, Canada and Antarctica could be lost "in a geologic instant."

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Science News: Scientists say they have seen the first direct evidence of lightning on Mars, in the form of electrical discharges during a Martian dust storm.

The finding has implications for human travel to the Red Planet and for studying possible origins of life on Mars, the authors say in a paper to appear in Geophysical Research Letters.

It has been thought that lightning might be possible on Mars. Bits of dust rubbing against each other in one of the planet’s famous dust devils could charge up the particles the same way that running on a carpet charges up socks. All that charge could then be discharged in a zap, either as lightning or a shock.

But catching Martian lightning in the act was difficult: The lightning bursts were too small to distinguish from the energy emanating from the planet itself. And the dust storms themselves obscured the faint glow that might have been visible from just above the red planet.

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Nature: Jupiter's moon Io is about the same size as our Moon, but the similarities end there.

Its motion around Jupiter is tightly constrained by its gravitational interactions with the giant planet and with two of Jupiter's other moons, Europa and Ganymede.

Io's orbital imprisonment is the cause of its spectacular volcanism. But Valéry Lainey, Jean-Eudes Arlot, Özgür Karatekin, and Tim Van Hoolst have provided evidence that Io is loosening the bonds that hold it in its unexpectedly elliptical path around Jupiter. If it eventually breaks free, the most volcanically active object in our Solar System will become dormant.

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SPACE.com: There have been raging debates over the years as to whether there is frozen water on the moon or not.

Earlier today two NASA spacecraft, the Lunar Reconnaissance Orbiter and the LCROSS impactor, blasted off on NASA's first mission to the moon in more than a decade.

Any ice they discover could not only answer some challenging questions about the geological history of the Moon, but also to support further space exploration.

ScienceNOW: Taming the infamous San Andreas fault with buried nuclear bombs or deep grease injections is the stuff of science fiction, but Mother Nature herself may be defusing a major fault in Taiwan, China.

Researchers are now showing that typhoons passing over the island have been triggering quakes that harmlessly release fault strain over hours and days rather than destructively over seconds or minutes. And these slow earthquakes, they speculate, may be staving off a big one.

Science: Among the greatest uncertainties in future energy supply and a subject of considerable environmental concern is the amount of oil and gas yet to be found in the Arctic.

By using a probabilistic geology-based methodology, the United States Geological Survey has assessed the area north of the Arctic Circle and concluded that about 30% of the world’s undiscovered gas and 13% of the world’s undiscovered oil may be found there, mostly offshore under less than 500 meters of water.

Oil resources are probably not sufficient to substantially shift the balance of power between oil producing countries, says the report.

The USGS study had been controversial as recommendations by scientists to not allow drilling without a proper environmental impact study were ignored by the previous administration, says a story published in the Independent last year.

Nature: Large earthquakes excite wave motion throughout the Earth, causing it to ring like a bell. The resulting ground motion, measured by seismometers, provides helpful constraints on Earth's internal structure through the study of its "normal modes"—free oscillations that occur at discrete frequencies.

Seismologically measurable oscillations have typical periods of a few minutes. But in work just published in Geophysical Journal International, Bruce A. Buffett, Jon Mound, and Andrew Jackson sound the Earth, in particular its core, through oscillations that have periods of decades.

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Nature: The noble gases emitted from deep inside the Earth have been sending mixed messages to those intent on deciphering them. A model that promises to help clear up the confusion is now on offer.

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Science: In geology textbooks, the fate of the oceanic crust seems straightforward. The ocean floor is created by upwelling of lighter magma at spreading ridges. The magma cools as it moves away from the ridge, forming a stiff layer or "plate" called the oceanic lithosphere. Having increased in density, it then descends back into the mantle in trench regions.

Precise seismic tomography studies have revealed that many descending slabs have a more complex evolution and have developed tears, detached from the surface plate, or even broken up into fragments.

In last week's Science, Obayashi and colleagues not only show clear tomographic evidence for the development of a vertical tear under southwest Japan, but have also found evidence for ongoing plate rupturing. The authors correlated the images directly with measurements of stress revealed by active seismic sources.

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Science News: A report given at the American Geophysical Union meeting in Toronto, Canada last week suggests that scientists have discovered a way to measure the Earth's magnetic field from 1000 years ago.

Geophysicist Annick Chauvin from the University of Rennes, France, and her colleagues have analyzed samples of bricks and mortar from 9th and 10th century French buildings.

They suggest that the Earth's magnetic field at the buildings locations peaked in 840 A.D. and measured about 70 microtesla, compared to 48 microtesla for the present day.

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Associated Press: A mass extinction some 260 million years ago may have been caused by volcanic eruptions in what is now China, new research suggests.

[Image credit: Re-evaluating vertical motion preceding the Emeishan continental flood basalt province, SW China]

The so-called Guadalupian Mass Extinction, devastating marine life around the world, was preceded by massive eruptions in the Emeishan geological province of Southwest China, says Paul Wignall of the University of Leeds and colleagues in Science.

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Science News: Swooping within 25 kilometers of Enceladus, the Cassini spacecraft has obtained additional evidence that the interior of this tiny, icy moon of Saturn may contain liquid water.

Hunter Waite of the Southwest Research Institute in San Antonio and his colleagues base their findings on close-up observations made with Cassini's Ion and Neutral Mass Spectrometer, which on March 12, 2008 and October 9, 2008 tasted the plumes of icy particles and water vapor known to spew from the moon.

In a research abstract for a talk at the 2009 Joint Assembly of the American Geophysical Union in Toronto, Waite and his collaborators cite two findings that they say "provide compelling evidence for the existence—today or in the recent past—of liquid water in Enceladus' interior."

Last year Waite spoke about the preliminary results of the March 12 flyby. It was "a completely unexpected surprise [that the chemistry of Enceladus interior] resembles that of a comet," said Waite. "To have primordial material coming out from inside a Saturn moon raises many questions on the formation of the Saturn system."

"Enceladus is by no means a comet," he added. "Comets have tails and orbit the sun, and Enceladus' activity is powered by internal heat while comet activity is powered by sunlight. Enceladus' brew is like carbonated water with an essence of natural gas."

SPACE.com: The first astronauts to walk on the moon in the 1960s and 1970s were inundated by sticky lunar dust that clung to their spacesuits whenever they ventured outside.

Now, four decades later, a self-funded study by an Australian physicist has found a link between the dust's stickiness and the angle of the sun at the time of each moonwalk.

The new research, which drew on the personal files and paper charts of physicist Brian O'Brien of Perth, suggests that future lunar astronauts may have greater problems with dust adhesion in the middle half of the day than NASA's Apollo missions faced in the early morning.

The MIT model is said to be the only one that incorporates among its variables possible changes in economic growth and other human activities and draws on peer-reviewed science on the climatic effects of atmospheric, oceanic and biological systems.

After running the model 400 times with slight variations in the inputs, the new predictions are for surface temperatures to warm by 6.3 to 13.3 degrees Fahrenheit. The prediction is for a 9.4-degree increase in the median temperature, more than double the 4.3 degrees predicted in a 2003 simulation.

Spirit has been roaming the red planet for more than five years, but its roving days could be over unless scientists and engineers back on Earth can figure out how to get the robot unstuck.

Within 100 million years of being formed, the young Earth was hit by a rogue planet, the debris from which ultimately formed the Moon, melting the Earth's surface. For the next 600 million years the planet was bombarded by debris and meteors that heated up both land and oceans. Few, if any, rocks remain from before the end of this era, with the oldest currently known being from 4.03 Gyr ago.

The earliest know isotopic evidence for life is at 3.8 Gyr, although its findings remain controversial.

For years geological models suggested that the oceans, where life is thought to have originally formed were sterilized during this period.

This left two uncomfortable conclusions—that life originated more than once, or that life started elsewhere in the solar system.

This story began to change with the discovery of zircons that pre-date the late bombardment. Zircons are telltale mineral inclusions in ancient rocks, and the evidence from them supported the idea that between 4.38–3.85 Gyr the Earth had liquid water, crustal recycling, a granitoid crust and low-temperature processes occurring at the boundaries of tectonic plates.

Abramov and Mojzsis's research now suggests that the conditions were never severe enough to sterilize Earth, eliminating the need for more esoteric solutions for how life survived on the early Earth.

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But there is another line of research that needs exploring: The overall impact of human-made orbital debris, solid and liquid propellant discharges, and other space age substance abuse that winds up in a high-speed dive through Earth's atmosphere.

There's a convenient toss-away line that is in vogue: that such space refuse simply "burns up"—a kind of out of sight, out of mind declaration.

What chemistry is involved given the high heating during reentry of space leftovers made of tungsten, beryllium, aluminum, and lots of composite materials? The impact of these materials on Earth's atmosphere—top to bottom—would seem worthy of investigation.

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Environmental News Network: A two-day workshop was held this week (May 11–12) between the US Environmental Protection Agency (EPA), Japan's Ministry of Environment (MOEJ), and Japan's Institute for Global Environmental Strategies to discuss key climate change issues.

Science: Early next month, NASA plans to launch an Atlas 5 rocket to the Moon. Piggybacking on the Atlas launch will be the Lunar CRater Observation and Sensing Satellite (LCROSS) mission. Upon reaching lunar orbit this fall, the spent Atlas upper stage will make a 7200-kilometer-per-hour impact on the Moon intended to blast lunar water—if any—high above the surface for all the world to see. No one is sure that the water is there, where exactly it would be, or how well the $80 million LCROSS will excavate it, but scientists are looking forward to the big splat.

MSNBC: Volcanoes threaten population of more than half a million people

And when Earth lies in the path of that blast, the flare can play havoc with power grids, disrupt radio communications, and disturb or disable satellites. Fifty years into the Space Age, Earth has avoided the worst the Sun can deliver - so far.

But with the Sun entering a period of increased activity, more frequent solar flares could be headed our way. This has many astronomers and companies asking if satellites and power grids are ready.

"In our view, Biosphere 2 was a tremendous success," said Bill Dempster, the project's engineering systems director and designer of the sphere's remarkable lungs. "Many people don't realize that hundreds of papers were written about it."

The rover, one of two NASA vehicles operating on Mars, has a broken right wheel. It has dust on its solar panels. It's operating at about 30 percent of normal power. Various sensors and software programs have gone screwy.

Then, on April 9, Spirit refused to wake up. The rover is designed to sleep at night, when there is no sunlight hitting the solar panels. But Spirit snoozed right through its wake-up call. It happened three times in succession. Finally a backup timer got Spirit up and moving again after a 27-hour slumber.

Using interferometry--subtracting one picture from the other--Italian scientists overlaid the two radar pictures of the region to produce a map of colored waves.

Each colored ring is a measure of how much the ground has moved as a result of the earthquake.

The large green square represents the location of the main shock; the smaller green squares show large aftershocks. Along the yellow line east of L’Aquila geologists found an alignment of surface breaks after the quake, which indicate the orientation of the rupture. The colored wave pattern follows those breaks exactly, indicating that the ground had moved a few inches down to the left side of the yellow line. This movement is also represented by the black and white fault plane solution on the left.

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ESO News: Well-known exoplanet researcher Michel Mayor today announced the discovery of the lightest exoplanet found so far. The planet, "e", in the famous system Gliese 581, is only about twice the mass of our Earth. The team also refined the orbit of the planet Gliese 581 d, first discovered in 2007, placing it well within the habitable zone, where liquid water oceans could exist. These amazing discoveries are the outcome of more than four years of observations using the most successful low-mass-exoplanet hunter in the world, the HARPS spectrograph attached to the 3.6-metre ESO telescope at La Silla, Chile.

At the time, some observers put the odds of such an event occurring at millions, maybe billions, to one.

But experts had been warning for years that useable space was becoming crowded, boosting the possibility of a serious collision

Perhaps no discovery was more surprising than the detection of an odd type of salt that Phoenix scientists think could have an important impact on the Martian water cycle and the planet's ability to support life.

In a set of papers presented last week at the 40th Lunar and Planetary Science Conference (LPSC) in The Woodlands, Texas, several Phoenix team members put forth their ideas on how the class of salts, called perchlorates, might affect Mars's water cycle; how it might boost or inhibit potential Martian life; how it might form a sludge underneath Mars' polar cap, lubricating them and allowing them to flow, as glaciers do on Earth; and how the salt even got there in the first place.

Their work has already helped surgeons find the location of a potentially life-threatening blood clot in a patient's heart.

Using sophisticated computer modelling developed to explore the flow of liquid metal through rocks, the scientists were able to show doctors where the patient's blood was gathering in a pool in their heart due to a blood clot.

Nature: Efforts intensify after eruptions in Alaska and Chile.

Physics Today: Updated 4/8/2009 An earthquake measuring 6.3 on the Richter scale hit central Italy at 1:32 GMT. last night causing thousands of people to lose their homes more than 250 deaths (see USGS map below).   "It was felt across the whole of Italy, but most strongly in central Italy," said Stuart Sipkin, a geophysicist at the US Geological Survey's (USGS's) National Earthquake Information Center.

The region had experienced a large number of minor tremors over the past four months, including a 4.0-magnitude event on 30 March.

Most of the damage surrounds the city of L'Aquila, which includes one of the oldest centers of learning in Europe, the University of L'Aquila. More than 4,000 buildings in the city have collapsed.

"We did know there would be quite a lot of damage because of the USGS Pager (Prompt Assessment of Global Earthquakes for Response) system," said Sipkin. "We can take our estimates of ground shaking and basically overlay this on a population density map, and we could see that [with the earthquake] a lot of people were exposed to large ground shaking," he added.

Enzo Boschi, the chairman of Italy's National Institute for Geophysics and Vulcanology, (INGV) told ANSA, an Italian news service, that the damage was extensive because the buildings were not designed to withstand earthquakes.

According to the New York Times, one of the four-story-high student dormitories collapsed, with one person dead and several missing. "This shouldn't have happened," said Gabriele Magrini, a physics student at the university. He told the New York Times that he was lucky enough to have been at a friend's house when the quake struck and that he had been waiting at the university since 4am, adding, "We've only seen two people come out. We're still waiting for 10."

Geographical history

Italy is a well-known complex earthquake zone, said Sipkin. "It's not a simple area like the West Coast of California where you have two large plates sliding against each other along the San Andreas fault.... You have the collision of Africa and Europe, its highly fractured and broken up, there's a lot of microplates moving around, which creates a lot of different types of fault action. This particular fault zone usually gives extensional earthquakes, but there's lots of different types of earthquakes that could happen."

There is a major fault line that runs north–south along Italy's Apennine Mountain Range and a minor east–west faultline that runs across the center of the country that produces frequent small earthquakes.

According to the US Geological Survey, the earthquake struck at a depth of 10 kilometers (6.2 miles), with an epicenter approximately 95 kilometers (60 mi) north–east of Rome, close to L'Aquila. The city has experienced major earthquakes in the past, but nothing on this scale since 1703.

"The duration of ground shaking depends on where you are. If you're on a hard surface, it ends pretty quickly, but if you're in a sedimentary built-up valley, then it would last longer," said Sipkin.

Two smaller quakes—(one at 4.8 on the Ritcher scale)—had hit the region the day before, which weakened many buildings before the main earthquake hit. Smaller aftershocks, which frequently occur after a significant earthquake, are still continuing.

''It was a common tremor for the Apennine mountain chain, one which occurs when underground shelves shift by ten centimeters or so,'' said Boschi. But it is impossible to predict when such tremors will happen, Boschi told ANSA, ''because the parameter variables change constantly. However, in the near future there should be no other ones similar in magnitude to the one last night, although we can expect aftershocks to continue in addition to the over 100 we have already recorded."

Controversy has erupted over Italian television reports that Gioacchino Giuliani, a laboratory technician, had predicted the earthquake but was told by authorities to take down his findings from a website.

Giuliani used a radon gas technique to make the earthquake prediction. Ignazio Guerra of the University of Calabria said that it is impossible to rely on that technique to predict an earthquake: ''There have been earthquakes without the emission of radon gas just as there have been emissions of radon gas without earthquakes. Thus this method is far from perfect."

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Gran Sasso laboratory undamaged in L'Aquila earthquake

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Quake 'Practically Destroys' University in Italy, With Some Students Trapped or Killed Chronicle of Higher Education

They eventually came to the attention of Nancy Evans, a no-nonsense archivist at the Jet Propulsion Laboratory.

Evans was at her desk in the 1970s when a clerk walked into her office, asking what he should do with a truck-sized heap of data tapes that had been released from storage.

"What do you usually do with things like that?" she asked.

"We usually destroy them," he replied.

"Do not destroy those tapes," Evans commanded.

She talked her bosses at JPL into storing them in a lab warehouse. "I could not morally get rid of this stuff," said Evans.

The full collection of Lunar Orbiter data, NASA's first mission to successfully visit the Moon, amounted to 2,500 tapes. Assembled on pallets, they constituted an imposing monolith 10 feet wide, 20 feet long and 6 feet high.

There was an additional problem, the rare machines that could read the tapes, were each 7 feet tall and weighing nearly a ton, and NASA didn't have one.

More than forty years later, a group of volunteers working at NASA's Ames Research Center in Mountain View, CA, have restored some of these early tape machines, and published the first of more than 2000 images from these early NASA missions (see above left).

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Lunar Orbiter Image Recovery Project

The research, currently available on arXiv, has been submitted to Nature for peer-review, but not everyone is convinced the group has found a supernova chemical fingerprint in the ice.

“The basic idea is an interesting one, but it’s way premature to accept these findings” at face value, comments Eric Wolff of the British Antarctic Survey in Cambridge, England. “If the authors could show convincingly that they had supernovas, this would be exciting...But I think we are a long way from that.”

The study answers the question of why giant dunes don't grow indefinitely, says Nick Lancaster, a geomorphologist at the Desert Research Institute in Reno, Nevada, who was not involved in the work.

This is the Mars Science Laboratory, the space agency's next big mission to the most Earth-like planet in the solar system. But it's been a magnet for controversy, and a reminder that the robotic exploration of other worlds is never a snap, especially when engineers decide to get ambitious.

The launch has been delayed for two years because of technical glitches. Approved at $1.63 billion, the mission's price tag will be at least $2.2 billion, NASA now estimates. Critics say the cost has really quadrupled since the project was first dreamed up. What no one can doubt is that ambitious missions tend to become costly ones, which jangles the nerves of officials who know how easy it is for a Mars mission to go bust.

Related Links
How to avoid contaminating planetary neighbors NPR

"It's been a superb flight," says David Pierce, chief of NASA's balloon programm at Goddard Space Flight Center's Wallops facility in Virginia. "We're proving this is a viable platform." Balloon flights are a lot cheaper than satellites for conducting experiments, but the short time they remain aloft has been a drawback to long-term cosmic-ray and high- altitude atmospheric experiments.

This new balloon design suggests that a $50,000 balloon could replace a million-dollar spacecraft for short-to-medium-term research experiments.

The New York Times: Nearly nine months after a devastating earthquake in Sichuan Province, China, left 80,000 people dead or missing, a growing number of American and Chinese scientists are suggesting that the calamity was triggered by a four-year-old reservoir built close to the earthquake's geological fault line.

ScienceNow: Astronomers today reported the discovery of a planet beyond our solar system that's just twice the diameter of Earth. But this new neighbor is far from habitable: CoRoT-Exo-7b is either a hellish world of erupting volcanoes and sizzling temperatures, or it's covered by a scalding ocean. Either way, the discovery could pave the way toward finding more Earth-sized alien worlds, some of which may actually be habitable.

The New York Times: In early 2003, a plume of methane gas rose from the surface of Mars. The big unanswered question is, What belched?

Subsurface Martian cows are highly unlikely. But scientists are seriously considering the possibility of bacteria.

MSNBC: Scientists believe rocks roll into the wind, not away from it

He also collects sand....

Now researchers are reporting that the abrupt cooling — which took place about 12,900 years ago, just as the planet was emerging from an ice age — may have been caused by one or more meteors that slammed into North America.

Nature: Signs of water and, perhaps, weather on a distant "hot Jupiter."

The New York Times: The first 700 million years of Earth’s 4.5-billion-year existence are known as the Hadean period, after Hades, or, to shed the ancient Greek name, Hell.

The New York Times: Still puzzling over how warm and wet Mars may have once been, scientists are now seeing global mineralogical signs that the planet was at least occasionally wet for the first two billion years of its existence.

BBC: The eruption of the Lusi mud volcano in Indonesia was caused by drilling for oil and gas, a meeting of 74 leading geologists has concluded.

The New York Times: A mega-tsunami rivaling the deadly one in 2004 struck southeast Asia more than 600 years ago, two teams of geologists said after finding sedimentary evidence in coastal marshes.

ABC News: Scientists are intrigued by the possibility that Earth-like planets could be evolving.

Science Magazine: Analysis of acoustic signals from lab samples links rapid pressure drops of pore fluids with low-frequency volcanic earthquakes.

The New York Times: In an article appearing in Friday’s issue of the journal Science, scientists report that portions of that bedrock are 4.28 billion years old, formed when Earth was less than 300 million years old.

The Wall Street Journal: The strongest storms are growing fiercer as the ocean warms, according to a new study released today in Nature that is sure to heat up a hurricane debate as Hanna and Ike swirl over the Atlantic.

Nature: Geologist David Rogers lambasted decision-makers after hurricane Katrina breached New Orleans' defenses in 2005. As this year's hurricane season heats up, how much has changed?

"The systems that generate elections and earthquakes are complex systems," said Keilis-Borok, who is now a professor of earth sciences at the University of California at Los Angeles. "They are not predictable by simple equations, but after coarse-graining -- averaging -- they become predictable."

In a paper in the International Journal of Forecasting, Lichtman predicted a political earthquake this November: The incumbent party will crumble, and Sen. Barack Obama will be elected president.

The problem is that researchers can't see much of what's going on beneath the plateau. Is the underlying rock strong and rigid or flowing like molasses? In the 22 August issue of Science, geoscientists Leigh Royden, B. Clark Burchfiel, and Robert van der Hilst of the Massachusetts Institute of Technology (MIT) in Cambridge argue that rock has flowed west to east beneath the plateau to inflate its eastern side and that the flow has been throttled by tectonic doings as far as thousands of kilometers away.

The proposed plan, which was sent as a document to the presidential campaigns of John McCain and Barack Obama, would cost the nation about $9 billion above the current $10 billion already allotted for fiscal years 2010-2014.

The groups include the American Meteorological Society and the American Geophysical Union.

"With more than a quarter of the U.S. gross national product sensitive to weather and climate, these events substantially impact our national health, safety, economy, environment, transportation systems, and military readiness," the document states.

The document stressed the need for more research in five areas:

• Observations. Fully fund the Earth observing system from satellite and ground-based instruments as recommended by the National Research Council.
• Computing. Greatly increase the computer power available for weather and climate research, predictions and related applications.
• Research and Modeling. Support a broad fundamental and applied research program in Earth sciences and related fields to advance present understanding of weather and climate and their impacts on society.
• Societal Relevance. Support education, training and communication efforts to use the observations, models and application tools for the maximum benefit of society.
• Leadership and Management. Implement effective leadership, management and evaluation approaches to ensure that these investments are done in the best interest of the nation.

The gradual weakening of the overall magnetic field can take hundreds and even thousands of years. But smaller, more rapid fluctuations within months may leave satellites unprotected and catch scientists off guard, new research finds.

The object, known as 2006 SQ372, is starting the outward portion of a 22,500-year orbit that will take it 150 billion miles away from the Sun

Science: The next generation of petroleum geologists will face unique challenges in meeting the world's energy demands, and flat federal funding means tight times in academia, but jobs abound in the petroleum, mining, and environmental consulting industries says Carolyn Gramling.

Science: To date, 307 extrasolar planets have been discovered and 29 multiple-planet systems have been discovered. The masses of the planets range from a few Earth masses up to several Jupiter masses, with orbital periods ranging from slightly over 1 day to several years. Unlike in our solar system, the orbital eccentricities of the extrasolar gas giant-sized planets may be large. In Science magazine, Edward W. Thommes, Soko Matsumura and Frederic A. Rasio describe how the range of periods, the eccentricities, and the diversity of the planetary systems have challenged the theories of planet formation, and propose an explanation--in terms of properties of the protoplanetary gas disk--of how this diversity may arise.

USA Today: Morten Bo Madsen spends his work day crunching data on a laptop seated in front of a clear plastic-covered box about the size of a widescreen computer monitor that emits a startlingly bright blue light.

Madsen is one of the 150 scientists and engineers working on NASA's Phoenix Mars Lander mission. The bright light keeps Madsen's internal clock in check, because Madsen is living on Mars time.

Mars' day is 40 minutes longer than Earth's, and the start of the Martian day is always changing with respect to Earth time, as a result of their respective orbital motions.

Living on a schedule that shifts forward by 40 minutes everyday can wreak havoc on the human body, creating an effect that is essentially like perpetual jet lag.

The Boston Globe: In a basement laboratory on Oxford Street, Harvard scientists seeking insight into Mars are shooting metal discs down a 20-foot-long gun barrel, pulverizing slivers of ice and rock.

"It is a very destructive way of doing science," said Sarah T. Stewart, the director of the Harvard Shock Compression Laboratory, who uses an oversized rifle to recreate the shockwaves that reverberate through a planet when a meteor crashes down.

Slamming objects together may seem more child's fantasy than laboratory life, but such brief, cataclysmic experiments can give researchers insight into everything from how materials hold up under extreme conditions to the chemistry of other worlds.

The Associated Press: At least one of many large, lake-like features on Saturn's moon Titan studied by the international Cassini spacecraft contains liquid hydrocarbons, making it the only body in the solar system besides Earth known to have liquid on its surface, NASA said Wednesday.

San Diego Union Tribune: The morning's 5.4 earthquake was centered well north, in San Bernardino County, but it still made buildings sway and pulses race throughout the San Diego region.

Wired: A moderately powerful earthquake struck southern California today. Though originating from the Chino Hills, it shook buildings 30 miles away in Los Angeles.

According to the United States Geological Survey, the quake initially measured 5.8 on the Richter scale -- comparable to the aftershocks of the massive earthquake that hit central China in May.

Science: Planetary scientists pursuing water and life on Mars must reconcile mounting evidence of a young planet awash in life-sustaining water with a growing realization that the martian surface was likely almost always dry

Washington Post: The mysterious sudden brightening and wavelike movements of the aurora borealis, also called the Northern Lights, are caused by periodic explosions of magnetic energy 80,000 miles above Earth, NASA researchers reported

Science: The international acoustics meeting recently held in Paris, France has had a number of stories picked up by science magazine that appeared in last week's issue. Speech can betray fatigue according to a new software program that analyzes the phonetic features of each person's speech.

Tigers and polar bears have had their hearing tested: The bears had a hearing range similar to that of humans, between 125 and 20,000 hertz; Tiger have hearing sensitive to infrasound, sound of lower frequency than most mammals perceive.

Acoustic instruments in the Indian ocean designed to detect nuclear explosions are now being put to use detecting ice cracking in Antarctic thousands of miles away. Getting a statistical handle on the numerous small ice cracks that are not visible from space will help determine whether the rate of ice-shelf degradation stays within natural bounds or steadily increases due to mechanisms such as climate change.

New ultrasound-based technologies are poised to probe the inner structure of bones and treat otherwise incurable cancers but the hype surrounding these techniques may be minimizing some of the risks associated with the techniques.

FInally, the newest generation of archaeologists may be wielding sensitive microphones and recorders to map hidden and abandoned structures according to several sessions in Paris devoted to archaeological acoustics.

Wired.com: In a study published in Nature, researchers led by Brown University geologist Alberto Saal found evidence of water molecules in pebbles retrieved by NASA's Apollo missions.

The findings point to the existence of water deep beneath the moon's surface, transforming scientific understanding of our nearest neighbor's formation and, perhaps, our own.

Nature News: An analysis of the seismic stress changes in China’s Sichuan basin has been published just 8 weeks after a magnitude 7.9 earthquake there killed more than 60,000 people and left millions homeless. The rapid calculation and publication1 brings accurate forecasting of aftershocks a step closer, experts say.

The New York Times: In the lab, the Moon rocks look nondescript — dark gray basalt, a whitish mineral called anorthosite and mixtures of the two with crystals thrown in. Yet nearly 40 years after the Apollo astronauts brought the first rocks back to Earth, these pieces of the Moon are still providing scientists with new secrets from another world.

Houston Chronicle: Mercury, the planet closest to the sun, appears to have at least one source of water, even though the temperatures on the tiny planet soar to 800 degrees Fahrenheit.

The existence of the water source on the dry, cratered planet was just one of the findings gathered by the Messenger spaceship when the unmanned craft sped within 124 miles of the planet on Jan. 14. NASA scientists described the observations last week.

Nature: A giant crater on the lunar farside holds the key to a catastrophic bombardment that reshaped the Moon, Earth and other planets. Eric Hand reports.

Nature News: The most dramatic cosmic impact in recent history has gathered up almost as many weird explanations as it knocked down trees, writes Duncan Steel.

space.com:The tide may be changing for the ocean suspected under the icy shell of Enceladus. Recent research has shown that this small moon of Saturn does not produce enough heat in its present configuration to keep water from freezing down to its core.

Nature: Earthquake takes nine lives as destruction arrives ahead of warning.

Reuters: European researchers said on Monday they discovered a batch of three "super-Earths" orbiting a nearby star, and two other solar systems with small planets as well.

They said their findings, presented at a conference in France, suggest that Earth-like planets may be very common.

The New York Times: After days of struggling with sticky Martian dirt, the Phoenix Mars Lander has unexpectedly succeeded in getting its first soil sample into an onboard laboratory for analysis, jubilant NASA scientists said on Wednesday.

The Associated Press: Pluto is finally getting its day in the sun, after being stripped of planetary status by astronomers two years ago.

From now on all similar distant bodies in the solar system will be called "plutoids." That's the decision by the International Astronomical Union, which met last week in Oslo, Norway, and announced the decision Wednesday.

ScienceNow: Scientists tracking a dramatic shrinkage in Arctic sea ice over the past few years have come to a worrisome conclusion: If the trend continues, it could speed up the melting of Arctic permafrost as well. The environmental consequences of such a development are uncertain, but they could spell trouble for plants, animals, and humans in those regions that depend on solid ground underfoot.

The Los Angeles Times: If scientists can't get the soil sample to break into bits small enough to fit in the oven, they'll try another strategy.

ScienceNow: Saturn's spectacular ring system appears to be the picture of serene beauty. But the narrow F ring is actually a chaotic place, one that is constantly disturbed and reshaped by its resident population of small moonlike objects. Now scientists are finally shedding light on what makes the ring so unruly.

Nature: Volcanic vents give a glimpse of a world without corals and other creatures.

Science: Mountains grow so slowly that no one would notice--or so conventional thinking would have it. But a group of geoscientists is arguing that about 8 million years ago, the central Andean plateau, at least, sprang upward so fast that modern surveying techniques could have revealed the uplift in a few years. It happened, they think, when the deep root of dense rock that anchored the Andes rapidly fell away. The new geochemical evidence of rapid uplift "is really beautiful stuff," says tectonophysicist Peter Molnar of the University of Colorado, Boulder. Lovely or not, the new paleo-elevation data will be facing some tests of their own.

Los Angeles Times: Ground operations began Monday at the Phoenix landing site at Mars' north pole, with the latest images from the robotic lander showing a bizarre, checkerboard landscape apparently shaped by the movement of ice lying only inches beneath the surface.

[From NASA's Phoenix spacecraft is ready to get its hands dirty on Mars - Los Angeles Times]

NPR: Walter Mooney, a research seismologist with the U.S. Geological Survey in Menlo Park, Calif., says the aftershocks following the earthquake in China are typical so far, but there's no real way to predict them. Mooney tells NPR's Melissa Block his Chinese counterparts are surprised by the extent of the damage and loss of life after the quake.

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Various: NASA's Mars Phoenix space probe has survived re-entry through the Martian atmosphere and landed close to the north martian pole. Yesterday, NPR's Joe Palca described what scientists hope to achieve with this mission, before updating NPR's audience this morning with news from NASA's Jet Propulsion Laboratory where jubilant mission control staff has gathered to watch the landing yesterday evening.

Unlike the two previous rover missions to Mars, Spirit and Opportunity, which were cushioned when they hit the surface, Phoenix used parachutes and thrusters to control its descent. As Reuters Irene Klotz reports NASA's space sciences chief Ed Weiler said, "I kept thinking, 'I wish Phoenix had airbags.'"

New York Times reporter Kenneth Chang leads with Phoenix transmitting photos back to Earth of the surface. "I know it looks a little like a parking lot,” said the mission’s principal investigator Peter H. Smith of the University of Arizona, “but it’s a safe place to land.”

“There’s ice under this surface,” Smith said. “It doesn’t look like it. You don’t see ice, but it’s down there.”

As space.com's Andrea Thompson discovers, Phoenix is designed to test the Martian soil and ice for signs that the water was once liquid, to see if it could have created a habitable zone for microbial life at some point in the past. The instruments include a robotic arm that will scoop up dust and ice, as well as a wet chemistry lab and tiny ovens that will analyze the soil to see what compounds might be in it.

"The science team has been waiting patiently... and they are anxious to use their instruments," said Smith. Over the next three months the science teams will collect as much data as possible from the spacecraft says Los Angeles Times staff writer John Johnson Jr.

Mars has been a risky venture for many space agencies, with a high rate of failure. Of the 39 missions to the red planet only a few have reached the surface and sent data back to Earth reports NPR's Virginia Hughes and Alejandra Garcia. The Independent's Steve Curtis looks at the difficulties in designing a probe to land on Mars. Meanwhile, Washington Post writer Marc Kaufman is one of the few reporters to point out the reason for Phoenix's name, the fact the spacecraft was built out of the spare parts of two earlier Mars missions that were canceled. Kaufman's piece has a nice slide show of the spacecraft. The BBC has video of the press conference and touchdown.

Phoenix is also another first for NASA, in that it is the first time that a NASA mission will be run from an operations center at a university, the University of Arizona.

Related Links
NASA Space Probe Approaches the Red Planet NPR
Scientists Excited About Boring Mars Landing Site NPR
Mars Lander Transmits Photos of Arctic Terrain New York Times
Spacecraft Lands Safely at Mars North Pole Reuters
Touchdown! Phoenix Spacecraft Lands on Mars Space.com
Phoenix spacecraft lands on Mars Los Angeles Times
Strife on Mars: Designing a probe to survive the red planet The Independent
Mars Craft Succeeds in Soft Landing Washington Post
Historic pictures sent from Mars BBC
Past Blasts to Mars: A brief history of Mars missions NPR
Phoenix operations center, University of Arizona

Nature News: Greenhouse-gas concentrations are higher today than they have been at any point in hundreds of millennia, according to researchers who have analysed tiny air bubbles trapped in Antarctic ice that dates back 800,000 years.

Atmospheric levels of carbon dioxide are now more than 28% higher than at any other point in the time period covered by the samples, according to Thomas Stocker, one of the authors of two studies in this week's Nature.

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Nature: The tectonic patterns and stress history of Europa are exceedingly complex and many large-scale features remain unexplained. Now Paul Schenk, Isamu Matsuyama & Francis Nimmo in this week's Nature have mapped troughs and depressions on Europa that indicate some features are caused by 'true polar wander'. In other words, they discovered that by re-orientating Europa's floating outer ice shell about Jupiter's tidal axis, and treating the surface as totally decoupled from any rocky interior mass, the tidal forces place on this shell by Jupiter's gravitational pull induce stress fractures seen on the surface of the moon.

These depressions also appear to be geographically related to other large-scale bright and dark lineaments4, 5, suggesting that many of Europa's tectonic patterns may also be related to true polar wander.

Physics Today: The magnitude 7.9 earthquake that struck near Chengdu May 12 has killed thousands and made millions homeless. It is the largest earthquake to hit China since 1976. According to the US Geological Survey the quake occurred as the result of motion on a northeast striking reverse, or thrust, fault, on the northwestern margin of the Sichuan Basin. The earthquake's epicenter and focal mechanism are consistent with it having occurred as the result of movement on the Longmenshan fault or on a tectonically related fault. The earthquake reflects tectonic stresses resulting from the convergence of crustal material slowly moving from the high Tibetan Plateau, and the strong crust underlying the Sichuan Basin and southeastern China (see maps below). "Earthquakes in this part of China are infrequent but not unexpected" says Harley Benz, Scientist-in-Charge with the USGS's National Earthquake Information Center.

Chengdu has a population of 2 million, with another 9 million in the surrounding urban area, and is about 90 km southeast of the epicenter. Many International companies, such as IBM, Symantec, Microsoft, Intel, Fujitsu, NEC, Motorola, and Nokia, have factories and offices in the region as part of Chengdu's High-Tech Industrial Development Zone. None of those companies are reporting any deaths of employees or major damage to their facilities. The SINA website has photos of the damage done in the city and surrounding towns.

View Larger Map

On a continental scale, the seismicity of central and eastern Asia is a result of northward convergence of the India plate and the Eurasia plate with a velocity of about 50 mm/y. The convergence of the two plates is broadly accommodated by the uplift of the Asian highlands and by the motion of crustal material to the east of the uplifted Tibetan Plateau.

"For this earthquake, because of its size, we should expect to see lots of aftershocks," says Benz. "In the first few hours following the magnitude 7.9, we recorded more than 13 earthquakes, the largest being a magnitude 6. The earthquakes are being located along a northeast trending fault, and they extend over a region about 100 kilometers, or 60 miles, which is consistent with the size of this earthquake.

"In terms of the total number of aftershocks, aftershocks from an earthquake, typically this size, will be occurring weeks and months from now, but typically with time, the number of earthquakes will go down, and the size of the earthquakes will go down, but there are chances of having other large, damaging earthquakes as part of this sequence occurring in the new few days and weeks."

Update 5/27/2008 According to the China Daily, an aftershock on Sunday that was 6.4 on the Richter scale destroyed 71,000 more homes and killed 6 people. The current death toll from the initial earthquake has topped 50,000.

Science: More than 400,000 asteroids have been identified in the solar system to date. These objects are thought to be the surviving remnants of the planetesimals that formed the planets about 4.6 billion years ago. The ages and mineralogical characteristics of these planetesimals can be estimated through high-precision laboratory analyses of the compositional and isotopic properties of meteorites, of which more than 30,000 samples exist.

Until now there has been no way to estimate when an asteroid formed, other than assuming that its age was similar to that of most meteorites. In the 25 April Science there is a new paper that present results of a remote spectroscopic study to show that a number of asteroids are enriched in the oldest known objects in the solar system (calcium-aluminum inclusions or CAIs), thereby making them the most ancient asteroids currently known.

New Scientist: A group of icy objects in the outer solar system appear years younger than their suspected age--1 billion years old.

The largest member of the family, called 2003 EL61, was discovered in 2005. In 2007, astronomers found five smaller objects travelling in similar orbits. Their paths suggested they all formed a single object that was broken apart in a collision more than a billion years ago.

A team led by David Rabinowitz of Yale University in New Haven, Connecticut, US, have released a paper on Arxiv that the brightness of the large object and four of the smaller ones (the fifth could not be observed) changes little when observed from various points along Earth's orbit. That suggests their surfaces are covered with fresh powdery ice no more than 100 million years old.

Science: Earth has its high-standing continents and low-lying ocean basins, thanks to plate tectonics. And Mars has its smooth northern lowlands and its cratered highlands. But there's no credible sign that plate tectonics ever operated on Mars, so how did a third of the planet come to be as much as 4 kilometers lower than the rest? For the past quarter-century, a leading theory has held that a giant impact battered the young planet and excavated the northern lowlands, but that idea seemed to have serious problems.

Now, two new studies purport to ease the difficulties with a giant impact. In one study, researchers reveal the true dimensions of the huge "Borealis basin," making it look much more like the crater of a giant impact. And a second group has run simulations that suggest how an impactor could have blasted out an 8000-kilometer-wide crater without melting it into an unrecognizable puddle of magma. "I think there's much to recommend [a giant impact] now with all this new work," says Sean Solomon, a planetary geophysicist at the Carnegie Institution of Washington's Department of Terrestrial Magnetism in Washington, D.C.

USA Today: NASA's new Mars rover aims high. It's bigger, more powerful and more sophisticated than any other robotic vehicle that has landed on another planet. It will try to answer a big question: Has life existed elsewhere in the solar system?

Its very ambition has gotten the rover in trouble. Thanks to a mix of technological setbacks and engineering misjudgments, the rover's epic scale is matched by epic problems.

The new rover, known as the Mars Science Laboratory, is $235 million, or 24%, over budget. Work on it has run so late that engineers are racing to prepare the rover for its blastoff in 2009. After that, the next good launch window, when Mars and the Earth are closest, is in 2011.

"They aimed high, and they got burned," says Arizona State University's Phil Christensen, a Mars scientist who helped review NASA's Mars program.

space.com: Astronomers have finally tracked down the missing starting point of one of the two types of solar wind.

The solar wind is a stream of electrically charged particles that flows constantly out from the sun in all directions. The particles can make the journey from the sun to the Earth in fewer than 10 days and, when the wind turns into a storm, create the magnificent auroras that dance across polar skies when they interact with the Earth's magnetic field.

The parts of the solar wind that emanate from the sun's equatorial region originate at the edges of bright regions in the sun's atmosphere and are released when the magnetic fields of two bright regions link up, scientists announced last week at the Royal Astronomical Society's National Astronomy Meeting in Belfast, Northern Ireland.

Science: "It's all a mush in my mind," said Michael Carr, talking about early Mars. That's quite a concession from one of the world's most experienced Mars geologists. After 10 hours of discussion on the state of early Mars, "it's frustrating," he said when asked to sum up a small premeeting workshop.* "Despite the beautiful data we've seen, we're no closer to understanding what [early Mars] climate was. And if it was warm and wet, what caused it to be warm and wet?"

Carr, who has been studying Mars since the early 1970s at the U.S. Geological Survey in Menlo Park, California, wrote the book on Mars. Actually, he wrote two of them: Water on Mars and The Surface of Mars. But that wasn't enough to sort out 40 years of data, much of it still coming from two rovers and two orbiters. The workshop focused on the first period of martian geologic history, called the Noachian--when water flowed on the surface, at least at times--and the transition into the Hesperian, a colder, drier time preceding the bone-dry deep-freeze of the past 3 billion years.

New York Times: Back in 2002, astronomers from Wesleyan University concluded that a star brightening and waning in an unusual 48-day rhythm was dipping in and out of stuff swirling around the star in a so-called protoplanetary disk. At the time one astronomer called the system “a Rosetta stone,” for understanding how planets form.

Now, after six more years of observation with an international group of astronomers, led by William Herbst of Wesleyan, researchers say they know what the stuff in this disk is. In a paper published on Thursday in the journal Nature, they report that it is made of sand-size grains, roughly a millimeter in diameter, which must have grown from infinitesimal dust particles over the three million years that the star, known as KH 15D, has been in existence.

CNN: NASA officials have directed the Mars Exploration Rover (MER) program to cut $4 million dollars from its $approximately 20 million dollar budget this year, and principal investigator Steve Squyres tells CNN that will likely mean science operations will have to be suspended for Spirit. The rover would be put in hibernation mode, and if all goes well it could be reactivated in the future in the event funding is restored.
Source: NASA/JPL-Caltech/Cornell

NASA Headquarters spokesman Dwayne Brown confirmed the budget directive has been issued. He said the reason behind the cut is to offset cost overruns with the Mars Science Laboratory, a follow-on rover set to launch next year.

Washington Post: Since astronomers identified the first planet outside our solar system 13 years ago there are now, according to the Extrasolar Planets Encyclopedia, 277 confirmed "extrasolar" planets, and quite a few more on the list of those suspected but not yet confirmed.

This explosion in planetary discoveries is taking place at such speed that even those most intimately involved are often amazed.

"This is an absolutely astounding time for this field," said Mark Swain of NASA's Jet Propulsion Laboratory, who last week reported finding the first "exoplanet" to have organic methane in its atmosphere.

The Washington Post conducted a discussion forum with MIT's Sara Seager on the state of extra planetary research on Monday afternoon.

New York Times: A new book, “Unknown Waters,” recounts the 1970 voyage of a submarine, the Queenfish, on a pioneering dive beneath the ice pack to map the Siberian continental shelf. The United States did so as part of a clandestine effort to prepare for Arctic submarine operations and to win any military showdown with the Soviet Union.

In great secrecy, moving as quietly as possible below treacherous ice, the Queenfish, under the command of Alfred S. McLaren, mapped thousands of miles of previously uncharted seabed in search of safe submarine routes. New York Times reporter William J. Broad talks to McLaren about his year-long voyage and the dangers of submarining under the Arctic pack ice.

Related links
Scientist at work: Alfred McLaren; Explorer of Arctic Depths Plans Another Trip North (New York Times October 29, 2002)

Science: Since 2004 the Cassini-Huyge