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LOS ANGELES, July 22 (Xinhua) -- Two teams of astronomers have discovered the largest and farthest reservoir of water ever detected in the universe, NASA's Jet Propulsion Laboratory (JPL) said on Friday.The water, equivalent to 140 trillion times all the water in the world's ocean, surrounds a huge, feeding black hole, called a quasar, more than 12 billion light-years away, according to JPL in Pasadena, California."The environment around this quasar is very unique in that it's producing this huge mass of water," said Matt Bradford, a scientist at JPL. "It's another demonstration that water is pervasive throughout the universe, even at the very earliest times. "This artist's concept illustrates a quasar, or feeding black hole, similar to APM 08279+5255, where astronomers discovered huge amounts of water vapor. Gas and dust likely form a torus around the central black hole, with clouds of charged gas above and below. X-rays emerge from the very central region, while thermal infrared radiation is emitted by dust throughout most of the torus. While this figure shows the quasar's torus approximately edge-on, the torus around APM 08279+5255 is likely positioned face-on from our point of view.A quasar is powered by an enormous black hole that steadily consumes a surrounding disk of gas and dust. As it eats, the quasar spews out huge amounts of energy. Both groups of astronomers studied a particular quasar called APM 08279+5255, which harbors a black hole 20 billion times more massive than the sun and produces as much energy as a thousand trillion suns.Astronomers expected water vapor to be present even in the early, distant universe, but had not detected it this far away before. There's water vapor in the Milky Way, although the total amount is 4,000 times less than in the quasar, because most of the Milky Way's water is frozen in ice. Water vapor is an important trace gas that reveals the nature of the quasar. In this particular quasar, the water vapor is distributed around the black hole in a gaseous region spanning hundreds of light-years in size (a light-year is about six trillion miles).Its presence indicates that the quasar is bathing the gas in X- rays and infrared radiation, and that the gas is unusually warm and dense by astronomical standards, JPL said.Although the gas is at a chilly minus 63 degrees Fahrenheit ( minus 53 degrees Celsius) and is 300 trillion times less dense than Earth's atmosphere, it's still five times hotter and 10 to 100 times denser than what's typical in galaxies like the Milky Way, said JPL.Measurements of the water vapor and of other molecules, such as carbon monoxide, suggest there is enough gas to feed the black hole until it grows to about six times its size, JPL said.Whether this will happen is not clear, the astronomers say, since some of the gas may end up condensing into stars or might be ejected from the quasar.Bradford's team made their observations starting in 2008, using an instrument called "Z-Spec" at the California Institute of Technology's (Caltech's) Submillimeter Observatory, a 33-foot (10- meter) telescope near the summit of Mauna Kea in Hawaii. Follow-up observations were made with the Combined Array for Research in Millimeter-Wave Astronomy (CARMA), an array of radio dishes in the Inyo Mountains of Southern California.The second group, led by Dariusz Lis, senior research associate in physics at Caltech and deputy director of the Caltech Submillimeter Observatory, used the Plateau de Bure Interferometer in the French Alps to find water. In 2010, Lis's team serendipitously detected water in APM 8279+5255, observing one spectral signature.Bradford's team was able to get more information about the water, including its enormous mass, because they detected several spectral signatures of the water, according to JPL.

WASHINGTON, July 27 (Xinhua) -- Astronomers studying observations taken by NASA's Wide-field Infrared Survey Explorer (WISE) mission have discovered the first known "Trojan" asteroid orbiting the sun along with Earth, the U.S. National Aeronautics and Space Administration (NASA) announced Wednesday in a statement.Trojans are asteroids that share an orbit with a planet near stable points in front of or behind the planet. Because they constantly lead or follow in the same orbit as the planet, they never can collide with it. In our solar system, Trojans also share orbits with Neptune, Mars and Jupiter. Two of Saturn's moons share orbits with Trojans.Scientists had predicted Earth should have Trojans, but they have been difficult to find because they are relatively small and appear near the sun from Earth's point of view."These asteroids dwell mostly in the daylight, making them very hard to see," said Martin Connors of Athabasca University in Canada, lead author of a new paper on the discovery to be published Thursday in the journal Nature. "But we finally found one, because the object has an unusual orbit that takes it farther away from the sun than what is typical for Trojans. WISE was a game-changer, giving us a point of view difficult to have at Earth 's surface."The WISE telescope scanned the entire sky in infrared light from January 2010 to February 2011. Connors and his team began their search for an Earth Trojan using data from NEOWISE, an addition to the WISE mission that focused in part on near-Earth objects, or NEOs, such as asteroids and comets. NEOs are bodies that pass within 28 million miles (45 million kilometers) of Earth 's path around the sun. The NEOWISE project observed more than 155, 000 asteroids in the main belt between Mars and Jupiter, and more than 500 NEOs, discovering 132 that were previously unknown.The team's hunt resulted in two Trojan candidates. One called 2010 TK7 was confirmed as an Earth Trojan after follow-up observations with the Canada-France-Hawaii Telescope on Mauna Kea in Hawaii.The asteroid is roughly 1,000 feet (300 meters) in diameter. It has an unusual orbit that traces a complex motion near a stable point in the plane of Earth's orbit, although the asteroid also moves above and below the plane. The object is about 50 million miles (80 million kilometers) from Earth. The asteroid's orbit is well-defined and for at least the next 100 years, it will not come closer to Earth than 15 million miles (24 million kilometers).

SAN FRANCISCO, July 28 (Xinhua) -- Amazon announced Thursday that it had reached an agreement with NBC Universal to allow its members to view certain movies from Universal Pictures on-line through its movie streaming service.According to the on-line retail giant, Oscar-winning movies such as "Eternal Sunshine of the Spotless Mind," "Gosford Park" and "Elizabeth" as well as other favorites like "Notting Hill" and "Billy Elliot" are part of the pact.The movies will be available to Amazon Prime members through its streaming service Prime Instant Video. Amazon Prime is a membership program that gives subscribers discounts on shipping for a 79 U.S. dollar annual fee.In February, Amazon said it would offer Prime customers unlimited access to an on-line video library. Last Wednesday, Amazon announced an accord with CBS that expanded the video library to more than 8,000 movies and TV shows. It said Thursday that the NBC deal will bring the number to more than 9,000.With the CBS, NBC Universal deals, Amazon steps up its rivalry against other movie streaming services, especially Netflix, a popular on-line and mail-order movie rental company which just boosted prices by 60 percent for some subscribers. Analysts said Amazon is trying to make the pitch to those customers who are disappointed with Netflix.In a second-quarter earnings letter to investors distributed on Monday, Netflix CEO Reed Hastings said Netflix had more than 24.6 million subscribers in the U.S. at the end of June and vastly more streaming content than its competitors."We haven't detected an impact on our business from Amazon Prime," he noted.

WELLINGTON, June 10 (Xinhua) -- Scientists have uncovered an almost complete picture of the remains of a geological formation that was one of the great wonders of the 19th Century world before it was covered in ash and water during a volcanic eruption.Scientists from New Zealand and the United States said Friday they had discovered the White Terraces, half of the famous Pink and White Terraces in the central North Island's Lake Rotomahana.The same group of scientists found the remnants of the pink half of the former world-famous tourist attraction on the lake floor in January.The Pink and White Terraces were buried by the eruption of Mount Tarawera 125 years ago on 10 June 1886. The two sets of cascading silica terraces were separated by several hundred metres.The two formerly glistening terraces were formed on the shores of the lake, where the silica rich waters were warmed by the magma beneath.In the late 19th Century, the cascading terraces attracted people from all over the world. The White Terraces were the larger and stretched to a height of 30 meters, forming a 240-meter face. Visitors could walk up to a crater platform where they could bathe in the clear blue waters in naturally-formed basins up to three meters deep.Project Leader Cornel de Ronde, of New Zealand's GNS Science geosciences research institute, said the sonar images from Lake Rotomahana showed the lake floor was covered overwhelmingly by soft sediment and mud.The side-scan sonar data of the lake floor was collected on the last day of the 10-day project at Lake Rotomahana during the southern summer, but was analyzed using new software, which became available after the data collection had finished.The scientists found the sonar data contained images of hard, crescent-shaped structures on the lake bed in a similar location to where the White Terraces were before the eruption of 1886.The structures were about 60 meters below the surface, a similar depth to the Pink Terraces found in January. The lake is about 122 meters deep at its deepest point."The two places on the lake floor where we encountered hard, up- standing crescent-shaped features correspond to the locations of the Pink and White Terraces before the Tarawera eruption," de Ronde said."The sonar image that appears to show part of the White Terraces came to light after the project had finished. It shows a horizontal segment of terraces over 100 meters long, although we don't know which part of the terraces it is."The rounded terrace edges are standing up from the lake floor by about a meter in some places. The sonar images of both sets of terraces are strikingly similar."Scientists managed to capture several color photographs of part of the Pink Terraces in January, but they did not lower an underwater camera over the White Terraces location during the project as they were unaware of what the sonar data was showing at the time.The fate of the remaining sections of the Pink and White Terraces was unclear, said a statement from GNS. "They might have been destroyed in the eruption. Alternatively, they could be lying under thick sediment, which is impenetrable to sonar signals sent out by the two autonomous underwater vehicles (AUVs) used in the survey."De Ronde said finding remnants of both sets of terraces was a remarkable outcome for the project."The project team was absolutely thrilled in January when we realised our AUVs had detected remnants of the Pink Terraces. Finding part of what we believe is the White Terraces as well has been surprising and very satisfying."The original aim of the project at Lake Rotomahana was to map the lake floor and investigate the extensive geothermal system under the lake and how it evolved from an on-land geothermal system to a submerged one. Anything else was a bonus," de Ronde said."It's gratifying to be part of a science project that can answer a century-old mystery about the fate of the Pink and White Terraces."De Ronde said the announcement of the find was timed to coincide with the 125th anniversary of Tarawera's eruption.The 10-day project was a collaboration involving GNS Science, Woods Hole Oceanographic Institution in Massachusetts, Lamont- Doherty Earth Observatory at Columbia University in New York, the National Oceanic and Atmospheric Administration in Seattle, and New Zealand's University of Waikato.

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