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WASHINGTON, Sept. 15 (Xinhua) -- A team of researchers has discovered a planet that orbits around a pair of stars, the U.S. space agency NASA announced Thursday.This is the first instance of astronomers finding direct evidence of a so-called circumbinary planet. A few other planets have been suspected of orbiting around both members of a dual-star system, but the transits of the circumbinary planet have never been detected previously.The team, led by Laurance Doyle of the SETI Institute in California, used photometric data from the NASA Kepler space telescope, which monitors the brightness of 155,000 stars.NASA's Kepler mission has discovered a world where two suns set over the horizon instead of just one. The planet, called Kepler-16b, is the most "Tatooine-like" planet yet found in our galaxy. Tatooine is the name of Luke Skywalker's home world in the science fiction movie Star Wars. In this case, the planet it not thought to be habitable. It is a cold world, with a gaseous surface, but like Tatooine, it circles two stars.They found the binary star system by detecting a system where the stars eclipsed each other from the perspective of the Kepler spacecraft. These stars have two eclipses: A primary eclipse when the larger star is partially blocked by the smaller star and a secondary eclipse where the smaller star is fully blocked by the larger star.But the researchers also noticed other times when the brightness of the two stars dropped, even when they were not in an eclipse position. This pattern suggested that there was likely a third object involved. The fact that these so-called tertiary and quaternary eclipses recurred after varying intervals of time, and were of different depths, indicated that the stars were in different positions in their orbit at each instance. This result showed that the tertiary and quaternary eclipses were being caused by something circling both stars, and not an object circling one or the other star.Measurements of the variations in the timing of all four types of eclipses, resulting from the mutual gravitational interactions of the two stars and the third body, demonstrated that the third object was, indeed, a planet. Their work indicates that the planet is less massive than Jupiter, possibly comparable in mass to Saturn, and that the larger of the two binary stars is smaller than our Sun.Their findings will be published Friday in Science."This discovery confirms a new class of planetary systems that could harbor life," Kepler principal investigator William Borucki said in a statement. "Given that most stars in our galaxy are part of a binary system, this means the opportunities for life are much broader than if planets form only around single stars. This milestone discovery confirms a theory that scientists have had for decades but could not prove until now."

LOS ANGELES, June 23 (Xinhua) -- The sun and its inner planets may have formed differently than previously thought, NASA's Jet Propulsion Laboratory (JPL) said on Thursday.Data revealed differences between the sun and planets in oxygen and nitrogen, which are two of the most abundant elements in our solar system, said JPL in Pasadena, Los Angeles.Although the difference is slight, the implications could help determine how our solar system evolved, JPL said.NASA researchers drew the conclusion after analyzing samples returned by NASA's 2004 Genesis mission, according to JPL.The air on Earth contains three different kinds of oxygen atoms which are differentiated by the number of neutrons they contain. Nearly 100 percent of oxygen atoms in the solar system are composed of O-16, but there are also tiny amounts of more exotic oxygen isotopes called O-17 and O-18. Researchers studying the oxygen of Genesis samples found that the percentage of O-16 in the sun is slightly higher than on Earth or on other terrestrial planets. The other isotopes' percentages were slightly lower."We found that Earth, the moon, as well as Martian and other meteorites which are samples of asteroids, have a lower concentration of the O-16 than does the sun," said Kevin McKeegan, a Genesis co-investigator from University of California, Los Angeles (UCLA) and the lead author of one of two papers published this week in Science journal. "The implication is that we did not form out of the same solar nebula materials that created the sun -- just how and why remains to be discovered." Another paper detailed differences between the sun and planets in the element nitrogen. Like oxygen, nitrogen has one isotope, N- 14, that makes up nearly 100 percent of the atoms in the solar system, but there is also a tiny amount of N-15. Researchers studying the same samples saw that when compared to Earth's atmosphere, nitrogen in the sun and Jupiter has slightly more N-14, but 40 percent less N-15. Both the sun and Jupiter appear to have the same nitrogen composition. As is the case for oxygen, Earth and the rest of the inner solar system are very different in nitrogen."These findings show that all solar system objects including the terrestrial planets, meteorites and comets are anomalous compared to the initial composition of the nebula from which the solar system formed," said Bernard Marty, a Genesis co- investigator from Petrographic and Geochemical Research Center in Fracne and the lead author of the other new Science paper. " Understanding the cause of such a heterogeneity will impact our view on the formation of the solar system."Data were obtained from analysis of samples Genesis collected from the solar wind, or material ejected from the outer portion of the sun. This material can be thought of as a fossil of our nebula because the preponderance of scientific evidence suggests that the outer layer of our sun has not changed measurably for billions of years."The sun houses more than 99 percent of the material currently in our solar system, so it's a good idea to get to know it better, " said Genesis Principal Investigator Don Burnett of the California Institute of Technology, Pasadena, California. "While it was more challenging than expected, we have answered some important questions, and like all successful missions, generated plenty more."Genesis was launched in August 2000. The spacecraft traveled to Earth's L1 Lagrange Point about one million miles from Earth, where it remained for 886 days between 2001 and 2004, passively collecting solar-wind samples.JPL managed the Genesis mission for NASA's Science Mission Directorate, Washington. The Genesis mission was part of the Discovery Program managed at NASA's Marshall Space Flight Center in Huntsville, Alasca.

He also said that China's track record of sharing knowledge with the World Bank was creating a "catalyst for consensus" and that placed the institutions in good stead to benefit from China's economic consistence."The Chinese policy mix includes a tool box of administrative measures ... In general, one of the lessons that the United States and others can learn (from China) is that to have supervisory policies for bank regulatory systems can be a useful part of the tool set."Aside from hinting that over-heating global real estate markets could benefit from China's regulatory tightening, Zoellick suggested if China moved to more market-exposed decision making, he hoped China's bank regulators would not step too far back."Over time China will be better served to move to more precise and market signals than more administration-based decisions. Over time China will want to move to more market based decisions ... but I don't want this to be interpreted that supervisors don't have to supervise," he said.

WASHINGTON, Aug. 24 (Xinhua) -- Online search engine Google Inc. has agreed to pay 500 million U.S. dollars to settle claims that it allowed online Canadian pharmacies to place advertisements targeting consumers in the United States, U.S. Justice Department announced Wednesday.The settlement, one of the largest ever in the United States, represents the gross revenue received by Google as a result of Canadian pharmacies advertising through Google's AdWords program, plus gross revenue made by Canadian pharmacies from their sales to U.S. consumers.The advertisements led to illegal imports of prescription drugs into the country, the Justice Department said.The shipment of prescription drugs from pharmacies outside the United States to customers in the United States typically violates the Federal Food, Drug and Cosmetic Act and in the case of controlled prescription drugs, the Controlled Substances Act.Google was aware as early as 2003, that generally, it was illegal for pharmacies to ship controlled and non-controlled prescription drugs into the United States from Canada."The Department of Justice will continue to hold accountable companies who in their bid for profits violate federal law and put at risk the health and safety of American consumers," Deputy Attorney General James Cole said in a statement."This settlement ensures that Google will reform its improper advertising practices with regard to these pharmacies while paying one of the largest financial forfeiture penalties in history," he said.Google had previously set aside that amount for a possible settlement over its advertising practices, according to a regulatory filing in May.

LOS ANGELES, June 7 (Xinhua) -- Salmonella, not E. coli, poses the greatest health threat to Americans, the U.S. Centers for Disease Control and Prevention (CDC) announced on Tuesday.Salmonella infections have risen 10 percent over the past 15 years, while several types of foodborne illness have been falling, the agency said in a report.Infections from Shiga toxin-producing E. coli O157 (the strain of most concern in the United States) have dropped almost in half and the rates of six other foodborne infections have been cut 23 percent, the CDC said.The agency issued the report as a deadly new strain of E.coli is spreading in several European countries."There are about 50 million people each year who become sick from food in the U.S.. That's about one in six Americans," CDC director Dr. Thomas R. Frieden said.The CDC attributed the reduction in infections from E. coli O157 to better detection and investigation of outbreaks, cleaner slaughterhouse methods, better testing of ground beef for E. coli, improved inspections of ground beef processing plants, regulations prohibiting E. coli O157 in ground beef and increased awareness of the importance of properly cooking beef.Other foodborne illnesses that fell in incidence over the same time period include those caused by the campylobacter, listeria, vibrio and yersinia pathogens.To reduce their risk of foodborne illness, people should assume that raw chicken and other meat have bacteria that can make you sick, the CDC said.In the kitchen, raw meats should not allow to contaminate counter tops or cutting boards and should be kept away from other foods, such as fruits and vegetables, the CDC advised.The agency also called on people to thoroughly cook meat, poultry, eggs and shellfish, while refraining from consuming unpasteurized milk, juice or soft cheese.

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