Science & Technology
Measurements by the MAGIC Telescope (Major Atmospheric Gamma-ray Imaging Cherenkov Telescope) on La Palma have shown that the universe is more transparent to high-energy radiation than previously assumed. A new publication in
Science with ETH Zurich participation describes how measurements of high-energy gamma radiation from 5.3 billion light years away are yielding new knowledge about the nature of the universe.
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| ©ETH Zurich
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| Diagrammatic representation of the measurement method for radiation in the (VHE) gamma region.
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Astronomers assume that our universe is approximately 14 billion years old. During this time it has changed greatly, for example through the formation of new galaxies that emit electromagnetic waves including light that can be perceived visually. A small fraction of the latter is absorbed, but the majority is retained in the universe. In this respect the universe can also be imagined as a background of invisible electromagnetic radiation. Since high-energy rays interact with low-energy ones, astronomers assumed for a long time that because of this enormous universal background radiation, only high-energy rays from very close active galaxies would be detectable on Earth - the remainder would be absorbed.
The remnant of a supernova called SN 1006 hangs like a gumball 7,000 light-years away in a composite image released last Tuesday by NASA.
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| ©NASA/CXC/Rutgers/G.Cassam-Chenao, J.Hughes et al.; Radio: NRAO/AUI/NSF/GBT/VLA/Dyer, Maddalena & Cornwell; Optical: Middlebury College/F.Winkler, NOAO/AURA/NSF/CTIO Schmidt & DSS
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| Supernova SN1006
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When it was first seen from Earth more than a thousand years ago, the explosion of the white dwarf star that created SN 1006 was reportedly brighter than Venus in the night sky.
David Mercado
ReutersThu, 10 Jul 2008 00:00 UTC
Archeologists have begun digging at an ancient ceremonial site in eastern Bolivia to piece together the rites and daily life of cultures dating as far back as 3,000 years ago.
Locals stumbled upon the remains while clearing the ground to build a new market in the picturesque town of Copacabana, a tourist hotspot on the shores of Lake Titicaca.
Tiny green and orange glass balls brought back from the moon nearly 40 years ago by astronauts show evidence that water existed there from the very beginning, scientists reported on Wednesday.
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| ©REUTERS/NASA
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| Green glass spherules collected from the Apollo 15 landing site at Hadley Rille on the Moon are shown in this undated handout photo. Scientists using a new kind of spectrograph have found evidence of water on the moon, contained in tiny volcanic glass beads collected by astronauts who landed on the Moon nearly 40 years ago. These samples represent volcanic deposits formed early in the Moon's geologic history.
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They used a new method of analyzing elements in the lunar sand samples to show strong evidence of water, dating back 3 billion years.
Scientists at the University of Cambridge have for the first time identified a key component to unravelling the mystery of room temperature superconductivity, according to a paper published in the journal Nature.
The quest for room temperature superconductivity has gripped physics researchers since they saw the possibility more than two decades ago. Materials that could potentially transport electricity with zero loss (resistance) at room temperature hold vast potential; some of the possible applications include a magnetically levitated superfast train, efficient magnetic resonance imaging (MRI), lossless power generators, transformers, and transmission lines, powerful supercomputers, etc.
Unfortunately, scientists have been unable to decipher how copper oxide materials superconduct at extremely cold temperatures (such as that of liquid nitrogen), much less design materials that can superconduct at higher temperatures.
Using remarkably sensitive new instruments, seismologists have detected minute geological changes that preceded small earthquakes along California's famed San Andreas Fault by as much as 10 hours. If follow-up tests show that the preseismic signal is pervasive, researchers say the method could form the basis of a robust early warning system for impending quakes.
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| ©NSF
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| Seismic waves were generated in the pilot hole of the San Andreas Fault Observatory at Depth, near Parkfield, Calif., and detected in the main hole, at depths of approximately one kilometer. An inverse correlation was found between changes in wave travel time and barometric pressure, causing increased stress in the rock.
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"We're working with colleagues in China and Japan on follow-up studies to determine whether this physical response can be measured in other seismically active regions," said Rice University seismologist Fenglin Niu, the study's lead author. "Provided the effect is pervasive, we still need to learn more about the timing of the signals if we are to reliably use them to warn of impending quakes."
Two Russian submersibles will make their first dive at Russia's Lake Baikal as part of scientific research for the Russian Academy of Sciences, a spokesman said on Wednesday.
The Mir-1 and Mir-2 deep-sea vehicles will perform 60 dives as part of unique research into the world's largest and deepest freshwater lake. The UNESCO World Heritage Site is 1,637 meters (5,371 ft) at its deepest point and contains around 20% of the world's fresh water.
"The first dive is scheduled for July 23," Anatoly Sagalevich said, adding that, "the expedition will be based at Baikal until mid-September," with the next phase in the research scheduled for next year.
An ancient organism from the pit of a collapsed volcano may hold the key to tomorrow's hydrogen economy. Scientists from across the world have formed a team to unlock the process refined by a billions-year old archaea. The U.S. Department of Energy Joint Genome Institute will expedite the research by sequencing the hydrogen-producing organism for comparative genomics.
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| ©Elizaveta Bonch-Osmolovskaya of the Russian Academy of Sciences
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| The East Thermal Field of the Uzon Caldera, Kamchatka, is home to hydrogen producing archaeon.
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When members of the Russian Academy of Sciences isolated a rare archaeal microorganism that breaks down cellulose and produces hydrogen, Biswarup Mukhopadhyay, an assistant professor with the Virginia Bioinformatics Institute at Virginia Tech, saw an opportunity to open a door for development of a cellulose-based high-temperature hydrogen production process. "Hydrogen can be easily converted to electrical and mechanical energy without any production of carbon dioxide," said Mukhopadhyay, whose lab specializes in very high temperature or hyperthermophilic archaea and in energy production.
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| ©Virginia Museum of Natural History
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| VMNH representatives at the stromatolite unveiling include Executive Director Tim Gette, Curator of Earth Sciences Dr. Jim Beard, and Assistant Curator of Paleontology Dr. Alton Dooley.
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Virginia Museum of Natural History scientists have confirmed that an approximately 500 million-year-old stromatolite was recently discovered at the Boxley Blue Ridge Quarry near Roanoke, Virginia. This specimen is the first-ever intact stromatolite head found in Virginia, and is one of the largest complete "heads" in the world, at over 5 feet in diameter and weighing over 2 tons.
ANIThu, 03 Jul 2008 15:05 UTC
Washington: An archaeological dig in northeastern Syria has pointed to a bizarre sacrificial ceremony, with the revelation of the remains of man, who may have been an acrobat at around 2300 B.C., along with remains of several rare horse-like animals.
According to a report by Discovery News, gory evidence of the entertainer's death, along with the remains of several rare horse-like animals, which appear to have been sacrificed as well, was found in the remains of a building at a site called Tell Brak, which was once the ancient city of Nagar.
