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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.

LOS ANGELES, July 5 (Xinhua) -- NASA's Juno spacecraft is 30 days away before its first launch window opens, the Jet Propulsion Laboratory (JPL) announced on Tuesday."One month from today, our first launch window opens at 11:34 a. m. EDT (8:34 a.m. PDT) and lasts 69 minutes," said Jan Chodas, Juno project manager from NASA's JPL in Pasadena, Los Angeles."Our primary launch period is 22 days long, and so if weather or other issues come up on Aug. 5, we have 21 more days to get Juno flying. Once we get Juno into space, it's a five-year cruise to Jupiter.""The launch window is the length of time allotted every day for an attempt to launch the spacecraft," said Chodas. "The launch period is the period of time in days when everything is in the right place to get your mission off to the right start."For a mission like Juno, getting everything in the right place includes considering the size of the rocket and spacecraft, where our home planet -- and in particular Juno's launch pad -- is pointed at any moment, and its location in space relative to other celestial objects like Juno's final target, Jupiter.Juno is scheduled to launch aboard a United Launch Alliance Atlas V rocket from pad 41-C at the Cape Canaveral Air Force Station, Florida.The solar-powered spacecraft will orbit Jupiter's poles 33 times to find out more about the gas giant's origins, structure, atmosphere and magnetosphere and investigate the existence of a solid planetary core.JPL manages the Juno mission for the principal investigator, Scott Bolton, of Southwest Research Institute in San Antonio.The Juno mission is part of the New Frontiers Program managed at NASA's Marshall Space Flight Center in Huntsville, Alaska. Lockheed Martin Space Systems, Denver, built the spacecraft.

XIAMEN, July 23 (Xinhua) -- A rescue and breeding base for endangered Chinese white dolphins started a trial operational period on Saturday in the southeastern seaside resort of Xiamen. The base is the first of its kind in the country.The base, located on the city's Huoshaoyu Islet, includes a rescue center and a breeding area and can accommodate up to four to six white dolphins, said Pan Shijian, vice mayor of Xiamen.Previously, rescuers had to return injured white dolphins back to the sea after giving them simple medical treatment due to the lack of a rescue base, Pan said."From now on, the base will be a hospital for injured or stranded dolphins," he said.The base will also be used as a rehabilitation center for children with infantile autism and brain paralysis, with the dolphins acting as "doctors" during the children's recovery period, he added.The Chinese white dolphin mainly lives in the seas around Xiamen and the Pearl River estuary in south China. The dolphins are under first-class state protection.The Chinese Academy of Fishery Sciences estimates that about 2,000 of the dolphins are living in China's seas.

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