Science & TechnologyS


Meteor

Asteroid isn't just a dry heap of rubble

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© NASA/ESA/J. Parker/SWRI/P. Thomas/Cornell U/L. McFadden/University of Maryland/M. Mutchler/Z. Levay/STScIThe largest asteroid, Ceres (shown), appears to contain a lot of water ice beneath its surface. Now ice has been detected on the surface of the asteroid 24 Themis, which lies about three times as far from the sun as Earth does.
Two independent teams have found what may be the first direct evidence of water ice on the surface of an asteroid. The discovery lends support to the idea that asteroids could have helped deliver water to the early Earth.

Asteroids are generally considered to be rocky, and comets icy. That's because ice in the early solar system is thought to have formed beyond a "snow line" lying somewhere between Mars and Jupiter. Asteroids forming beyond that boundary could contain ice.

But it is not clear how common ice might be in the main asteroid belt, because sunlight is expected to quickly vaporise ice on the surfaces of airless bodies that fly closer to the sun than Jupiter.

In 2008, however, Andrew Rivkin of Johns Hopkins University in Laurel, Maryland, and Joshua Emery of the SETI Institute in Mountain View, California, found hints that the asteroid 24 Themis, which sits in the main asteroid belt between Mars and Jupiter, could have water ice on its surface. The team found the water signal by measuring the spectrum of infrared light radiated by the object.

Now a second team has found the water ice signature using the same telescope, NASA's Infrared Telescope Facility in Hawaii.

The new observations suggest water ice, mixed with organic molecules, is "widespread on the surface of the asteroid", Humberto Campins of the University of Central Florida in Orlando reported at a meeting of the American Astronomical Society's Division of Planetary Sciences in Fajardo, Puerto Rico, last week.

Telescope

Asteroid is Actually a Protoplanet: Study of First High-resolution Images of Pallas Confirms

Pallas
© Science/AAASPallas's largest crater-like feature seen in the digital model (left) and from two perspectives: appearing face-on (upper right) and edge-on along the limb (lower right).
Britney E. Schmidt, a UCLA doctoral student in the department of Earth and space sciences, wasn't sure what she'd glean from images of the asteroid Pallas taken by the Hubble Space Telescope. But she hoped to settle at least one burning question: Was Pallas, the second-largest asteroid, actually in that gray area between an asteroid and a small planet?

The answer, she found, was yes. Pallas, like its sister asteroids Ceres and Vesta, was that rare thing: an intact protoplanet.

"It was incredibly exciting to have this new perspective on an object that is really interesting and hadn't been observed by Hubble at high resolution," Schmidt said of the first high-resolution images of Pallas, which is believed to have been intact since its formation, most likely within a few million years of the birth of our solar system.

"We were trying to understand not only the object, but how the solar system formed," Schmidt said. "We think of these large asteroids not only as the building blocks of planets but as a chance to look at planet formation frozen in time."

The research appears Oct. 9 in the journal Science.

Phoenix

Temple built for Greek goddess of divine retribution unearthed in Turkey

Archaeologists have found traces of a temple built for the Greek goddess of divine retribution, Nemesis, during excavations in the ancient city of Agora in the Aegean port city of Izmir in Turkey.

According to a report in Hurriyet Daily News and Economic Review, Akin Ersoy of Dokuz Eylul University's archaeology department and heading the archaeological excavations in the ancient city, said that there might be a temple built for Nemesis in the area.

Meteor

NASA Refines Asteroid Apophis' Path Toward Earth

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© UH/IA Asteroid Apophis was discovered on June 19, 2004.
Pasadena, California -- Using updated information, NASA scientists have recalculated the path of a large asteroid. The refined path indicates a significantly reduced likelihood of a hazardous encounter with Earth in 2036.

The Apophis asteroid is approximately the size of two-and-a-half football fields. The new data were documented by near-Earth object scientists Steve Chesley and Paul Chodas at NASA's Jet Propulsion Laboratory in Pasadena, Calif. They will present their updated findings at a meeting of the American Astronomical Society's Division for Planetary Sciences in Puerto Rico on Oct. 8.

Magnify

Stolen Egyptian Relics On Their Way Home

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© Getty Images A wall painting from the Valley of the Homecoming. Kings appears above. Five stolen, ancient Egyptian relics that are held at the Louvre will be returned to Egypt.
France decided on Friday to return to Egypt five relics stolen from Luxor's Valley of the Kings and sold to the Louvre, two days after Cairo severed ties with the Paris museum in protest.

A special commission of the French museums agency decided unanimously to hand over the five painted wall fragments after ruling that they were indeed stolen in the 1980s before ending up at the Louvre in 2000 and 2003.

"Restitution is now just a matter of weeks," said a culture ministry official, speaking on condition of anonymity.

Info

Specialty hospitals cherry-pick patients, exaggerate success.

California cardiac care hospitals studied in INFORMS annual meeting paper.

Although many specialized hospitals deliver better and faster services in cardiac care and other specialties, a paper being presented at the annual meeting of the Institute for Operations Research and the Management Sciences (INFORMS®) maintains that these hospitals cherry-pick patients to achieve these results, and that average patients actually receive worse care.

Robot

Israeli navy to deploy robot craft

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© UnknownThe Protector.
The Israeli navy will shortly begin deploying unmanned craft along the Mediterranean coast, particularly off the Hamas-held Gaza Strip in the south and Lebanon in the north where Hezbollah guerrillas operate.

These highly maneuverable unmanned surface vehicles, operated by remote control from land stations, can carry out a wide range of missions, such as patrolling coastal waters to counter gun-running and infiltration with less prospect of being detected than the much larger manned vessels.

"There are areas that the navy preferred to first enter in an unmanned capacity before a manned capacity," a senior navy officer told The Jerusalem Post Sunday in reference to the Gaza and Lebanon sectors.

Laptop

Kraken becomes first academic machine to achieve petaflop

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© The University of Tennessee and Oak Ridge National LaboratoryThis is the newly upgraded Kraken supercomputer, capable of a peak performance of more than one petaflop.
The National Institute for Computational Sciences' (NICS's) Cray XT5 supercomputer - Kraken - has been upgraded to become the first academic system to surpass a thousand trillion calculations a second, or one petaflop, a landmark achievement that will greatly accelerate science and place Kraken among the top five computers in the world.

Magnify

Radio Waves 'See' Through Walls

Walking
© Sarang Joshi and Joey Wilson, University of UtahOn the left, a person walks around inside a square of 28 radio transceivers in the Warnock Engineering Building's atrium at the University of Utah. The person creates "shadows" in the radio waves, resulting in the image displayed on right, in which the person appears as a reddish-orange-yellow blob.
University of Utah engineers showed that a wireless network of radio transmitters can track people moving behind solid walls. The system could help police, firefighters and others nab intruders, and rescue hostages, fire victims and elderly people who fall in their homes. It also might help retail marketing and border control.

"By showing the locations of people within a building during hostage situations, fires or other emergencies, radio tomography can help law enforcement and emergency responders to know where they should focus their attention," Joey Wilson and Neal Patwari wrote in one of two new studies of the method.

Both researchers are in the university's Department of Electrical and Computer Engineering - Patwari as an assistant professor and Wilson as a doctoral student.

Their method uses radio tomographic imaging (RTI), which can "see," locate and track moving people or objects in an area surrounded by inexpensive radio transceivers that send and receive signals. People don't need to wear radio-transmitting ID tags.

Saturn

Pallas is 'Peter Pan' Space Rock

Pallas space rock
© B.Schmidt2 Pallas is not quite a sphere
The Hubble telescope has provided new insight on 2 Pallas, one of the largest asteroids in the Solar System.

The nearly 600km-wide rock is an example of an object that started out on the process of becoming a planet but never grew up into the real thing.

Researchers have published a 3D model of the grapefruit-shaped mini-world in Science magazine.

Hubble's data makes it possible to discern surface features, including what appears to be a big impact crater.