Material online can seem ephemeral. Here's a welcome example of the opposite. Earlier this year a site called Deletionpedia launched with the sole aim of preserving all the pages deleted from Wikipedia.
There are already some 64,000 pages saved for posterity, with more accumulating every day. Some pages seem to have been deleted - and created - for political reasons.
Science & Technology
NASA's Center for Computational Sciences is nearly tripling the performance of a supercomputer it uses to simulate Earth's climate and weather, and our planet's relationship with the Sun.
NASA is deploying a 67-teraflop machine that takes advantage of IBM's iDataPlex servers, new rack-mount products originally developed to serve heavily trafficked social networking sites. The servers use an innovative design that saves on power and cooling costs by placing the servers sideways and using a liquid-cooled rear-door heat exchanger.
NASA is deploying a 67-teraflop machine that takes advantage of IBM's iDataPlex servers, new rack-mount products originally developed to serve heavily trafficked social networking sites. The servers use an innovative design that saves on power and cooling costs by placing the servers sideways and using a liquid-cooled rear-door heat exchanger.
Washington -- Data from the Ulysses spacecraft, a joint NASA-European Space Agency mission, show the sun has reduced its output of solar wind to the lowest levels since accurate readings became available. The sun's current state could reduce the natural shielding that envelops our solar system.
"The sun's million mile-per-hour solar wind inflates a protective bubble, or heliosphere, around the solar system. It influences how things work here on Earth and even out at the boundary of our solar system where it meets the galaxy," said Dave McComas, Ulysses' solar wind instrument principal investigator and senior executive director at the Southwest Research Institute in San Antonio. "Ulysses data indicate the solar wind's global pressure is the lowest we have seen since the beginning of the space age."
"The sun's million mile-per-hour solar wind inflates a protective bubble, or heliosphere, around the solar system. It influences how things work here on Earth and even out at the boundary of our solar system where it meets the galaxy," said Dave McComas, Ulysses' solar wind instrument principal investigator and senior executive director at the Southwest Research Institute in San Antonio. "Ulysses data indicate the solar wind's global pressure is the lowest we have seen since the beginning of the space age."
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| ©NASA |
Saturn's rings may be more massive than previously thought, and potentially much older, according to calculations that simulate colliding particles in Saturn's rings and their erosion by meteorites.
These results support the possibility that Saturn's rings formed billions of years ago, perhaps at the time when giant impacts excavated the great basins on the Moon. The findings also suggest that giant exoplanets may also commonly have rings.
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| ©Voyager 2, NASA |
| Saturn's rings may be more massive than previously thought, and potentially much older. |
These results support the possibility that Saturn's rings formed billions of years ago, perhaps at the time when giant impacts excavated the great basins on the Moon. The findings also suggest that giant exoplanets may also commonly have rings.
Using data from NASA's Wilkinson Microwave Anisotropy Probe (WMAP), scientists have identified an unexpected motion in distant galaxy clusters. The cause, they suggest, is the gravitational attraction of matter that lies beyond the observable universe.
"The clusters show a small but measurable velocity that is independent of the universe's expansion and does not change as distances increase," says lead researcher Alexander Kashlinsky at NASA's Goddard Space Flight Center in Greenbelt, Md. "We never expected to find anything like this."
Kashlinsky calls this collective motion a "dark flow" in the vein of more familiar cosmological mysteries: dark energy and dark matter. "The distribution of matter in the observed universe cannot account for this motion," he says.
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| ©NASA/WMAP/A. Kashlinsky et al. |
| Galaxy clusters like 1E 0657-56 (inset) seem to be drifting toward a 20-degree-wide patch of sky (ellipse) between the constellations of Centaurus and Vela. |
"The clusters show a small but measurable velocity that is independent of the universe's expansion and does not change as distances increase," says lead researcher Alexander Kashlinsky at NASA's Goddard Space Flight Center in Greenbelt, Md. "We never expected to find anything like this."
Kashlinsky calls this collective motion a "dark flow" in the vein of more familiar cosmological mysteries: dark energy and dark matter. "The distribution of matter in the observed universe cannot account for this motion," he says.
Tetrapods, the first four-legged land animals, are regarded as the first organisms that had fingers and toes. Now researchers at Uppsala University can show that this is wrong. Using medical x-rays, they found rudiments of fingers in the fins in fossil Panderichthys, the "transitional animal," which indicates that rudimentary fingers developed considerably earlier than was previously thought.
Our fish ancestors evolved into the first four-legged animals, tetrapods, 380 million years ago. They are the forerunners of all birds, mammals, crustaceans, and batrachians. Since limbs and their fingers are so important to evolution, researchers have long wondered whether they appeared for the first time in tetrapods, or whether they had evolved from elements that already existed in their fish ancestors.
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| ©Uppsala University |
| Scientists found rudiments of fingers in the fins in fossil Panderichthys, the "transitional animal". |
Our fish ancestors evolved into the first four-legged animals, tetrapods, 380 million years ago. They are the forerunners of all birds, mammals, crustaceans, and batrachians. Since limbs and their fingers are so important to evolution, researchers have long wondered whether they appeared for the first time in tetrapods, or whether they had evolved from elements that already existed in their fish ancestors.
Scientists are now able to better explain why Mars's residual southern ice cap is misplaced, thanks to data from ESA's Mars Express spacecraft - the martian weather system is to blame. And so is the largest impact crater on Mars - even though it is nowhere near the south pole.
Like Earth, Mars has frozen polar caps, but unlike Earth, these caps are made of carbon dioxide ice as well as water ice. During the southern hemisphere's summer, much of the ice cap sublimates, a process in which the ice turns straight back into gas, leaving behind what is known as the residual polar cap. The problem is that while the winter cap is symmetrical about the south pole, the residual cap is offset by some three to four degrees.
This misplacement, which has puzzled planetary scientists for years, was solved by scientists in 2005 but now, thanks to ESA's Mars Express, new information is available to explain the misplacement.
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| ©ESA; image courtesy of F. Altieri (IFSI-INAF) and the OMEGA team |
| This is a mosaic of images taken by the Mars Express's Visible and Infrared Mineralogical Mapping Spectrometer, OMEGA. It shows the residual south polar cap at the end of northern winter on the Red Planet. The cap appears clearly asymmetric, its centre being displaced by 3° from the geographic pole. |
Like Earth, Mars has frozen polar caps, but unlike Earth, these caps are made of carbon dioxide ice as well as water ice. During the southern hemisphere's summer, much of the ice cap sublimates, a process in which the ice turns straight back into gas, leaving behind what is known as the residual polar cap. The problem is that while the winter cap is symmetrical about the south pole, the residual cap is offset by some three to four degrees.
This misplacement, which has puzzled planetary scientists for years, was solved by scientists in 2005 but now, thanks to ESA's Mars Express, new information is available to explain the misplacement.
Maybe there is some hope for SC24 ramping up this year yet. This appears to be the largest SC24 spot to date. Previous SC24 spots have faded quickly, we'll see how long this one lasts.
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| ©NASA |
The International Astronomical Union (the IAU) has announced that the object previously known as 2003 EL61 is to be classified as the fifth dwarf planet in the Solar System and named Haumea.
The decision was made after discussions by members of the International Astronomical Union's Committee on Small Body Nomenclature (CSBN) and the IAU Working Group for Planetary System Nomenclature (WGPSN). This now means that the family of dwarf planets in the Solar System is up to five. They are now Ceres, Pluto, Haumea, Eris and Makemake.
The discovery of Haumea was announced in mid-2005, and the object was initially given the provisional designation of 2003 EL61. It is a bizarre object with a shape resembling a plump cigar. Its diameter is approximately the same as that of the dwarf planet Pluto; however, its odd shape means that it is much thinner. It is also known to be spinning very fast, making one rotation in about four hours. Some have suggested that this rapid rotation could be the reason Haumea came to look as it does - the dwarf planet has been drawn out and elongated by its swift spin.
The decision was made after discussions by members of the International Astronomical Union's Committee on Small Body Nomenclature (CSBN) and the IAU Working Group for Planetary System Nomenclature (WGPSN). This now means that the family of dwarf planets in the Solar System is up to five. They are now Ceres, Pluto, Haumea, Eris and Makemake.
The discovery of Haumea was announced in mid-2005, and the object was initially given the provisional designation of 2003 EL61. It is a bizarre object with a shape resembling a plump cigar. Its diameter is approximately the same as that of the dwarf planet Pluto; however, its odd shape means that it is much thinner. It is also known to be spinning very fast, making one rotation in about four hours. Some have suggested that this rapid rotation could be the reason Haumea came to look as it does - the dwarf planet has been drawn out and elongated by its swift spin.
By tracking the amount of light emitted by Baghdad neighborhoods at night, a team of UCLA geographers has uncovered fresh evidence that last year's U.S. troop surge in Iraq may not have been as effective at improving security as some U.S. officials have maintained.
Night light in neighborhoods populated primarily by embattled Sunni residents declined dramatically just before the February 2007 surge and never returned, suggesting that ethnic cleansing by rival Shiites may have been largely responsible for the decrease in violence for which the U.S. military has claimed credit, the team reports in a new study based on publicly available satellite imagery.
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| ©University of California - Los Angeles |
| Satellite image of night lights in Baghdad. By tracking the amount of light emitted by Baghdad neighborhoods at night, a team of UCLA geographers has uncovered fresh evidence that last year's U.S. troop surge in Iraq may not have been as effective at improving security as some U.S. officials have maintained. |
Night light in neighborhoods populated primarily by embattled Sunni residents declined dramatically just before the February 2007 surge and never returned, suggesting that ethnic cleansing by rival Shiites may have been largely responsible for the decrease in violence for which the U.S. military has claimed credit, the team reports in a new study based on publicly available satellite imagery.
