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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).

BEIJING, Aug. 12 (Xinhuanet) -- Engineers at the University of Illinois have unveiled novel, skin-mounted electronics whose circuitry bends, wrinkles, and even stretches with skin, according to media reports quoting the Science Friday.The device platform includes electronic components, medical diagnostics, communications, and human-machine interfacing on a patch so thin and durable that it can be mounted to skin much like a temporary tattoo, the jounral described.What's more, the engineers demonstrated the invention across a wider range of components, including LEDs, transistors, wireless antennas, sensors, and conductive coils and solar cells for power."We threw everything in our bag of tricks onto that platform, and then added a few other new ideas on top of those to show that we could make it work," said engineering professor John A. Rogers in a news release.

BEIJING, Sept. 2 (Xinhuanet) -- The amount of space junk orbiting the Earth could cause fatal leaks in spaceships or destroy valuable satellites, according to a report released by the U.S. National Research Council.Computer models have shown that the number of orbital debris "has reached a tipping point, with enough currently in orbit to continually collide and create even more debris, raising the risk of spacecraft failures," the Research Council said Thursday.So far, there are 22,000 pieces of debris large enough to track from the ground, but smaller objects could still cause serious damage.New international regulations are needed to limit space junk.And more researches should be done to test the possible use of launching magnetic nets or giant umbrellas to push the debris further towards the Earth where it would burn up, or into a higher but safer orbit.

CANBERRA, Aug. 29 (Xinhua) -- An Australia report released on Monday draws a direct link between inaction on climate change and long-term social and mental health problems.The Climate Institute report, A Climate of Suffering: The Real Cost of Living with Inaction on Climate Change, points that in the wake of extreme weather in Australia, such as cyclones and droughts, there is an increase in depression, anxiety, post- traumatic stress and substance abuse.As many as one in five people reported "emotional injury, stress and despair" in the wake of these events.The report also warns continuing catastrophic weather events are creating anxiety and insecurity for children at levels not seen since the Cold War.It claims one in 10 children of primary school age showed symptoms of post-traumatic stress disorder after Cyclone Larry in 2006.According to Professor Ian Hickie, from the Brain & Mind Institute, regional and remote communities are most vulnerable to the impact of climate change.He said a recent study of rural New South Wales where, following the long drought, self-harm and suicide rose by up to eight percent."I think what we are seeing now is a much more significant counting of not just the short-term costs and reactions but the longer-term costs, the loss of community cohesion and that being essential to people's long-term mental health," Professor Hickie."The drought was a particularly instructive event for everyone in Australia and we saw a lot of focus for the first time on the mental health effects, particularly suicides in rural families, the effect on rural communities of prolonged examples of weather change," Hickie said.Climate Institute chief executive John Connor said that not only did natural disasters cost taxpayers about nine billion U.S. dollars last year, but there are also damaging Australia's social fabric.He said that with Australian regions increasingly exposed to extreme weather, recognizing and managing the risks of climate change is essential, and it is an insurance policy to protect Australia's communities.The study came as the political and social debate over Australian federal government's proposed carbon tax intensifies.In 2007, a report by the Commonwealth Scientific and Industrial Research Organization (CSIRO) projected the effects of various greenhouse gas emission scenarios for 2030, 2050 and 2070.It said droughts were likely to become more frequent, fire danger was set to increase and tropical cyclones were likely to become more intense.

WASHINGTON, Sept. 27 (Xinhua) -- Debris from NASA's decommissioned Upper Atmosphere Research Satellite (UARS) that crashed to Earth on Saturday fell harmlessly in a remote area of the South Pacific Ocean, NASA said on Tuesday.According to the space agency, the Joint Space Operations Center at Vandenberg Air Force Base in California has determined the satellite entered the atmosphere over the Pacific Ocean at 14.1 degrees south latitude and 170.2 west longitude at midnight EDT Saturday. The debris field is located between 300 miles and 800 miles downrange, or generally northeast of the re-entry point."This location is over a broad, remote ocean area in the Southern Hemisphere, far from any major land mass," NASA announced, adding that it is "not aware of any possible debris sightings from this geographic area."NASA scientists estimated a 1-in-3,200 chance a satellite part could hit someone on earth. Therefore, any individual's odds of being struck are about one in 21 trillion.The UARS satellite, launched in 1991 from a space shuttle, was the first multi-instrumented satellite to observe numerous chemical constituents of the atmosphere with a goal of better understanding atmospheric photochemistry and transport.

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