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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, June 24 (Xinhua) -- Near-Earth asteroid 2011 MD will whip past Earth on June 27, but will not pose any threat, NASA's Jet Propulsion Laboratory (JPL) said on Friday.The asteroid will pass only 12,000 kilometers (7,500 miles) above the Earth's surface at about 9:30 EDT, according to JPL in Pasadena, Los Angeles.This small asteroid, only 5-20 meters in diameter, is in a very Earth-like orbit about the Sun, but an orbital analysis indicates there is no chance it will actually strike Earth on Monday, JPL said.If a rocky asteroid the size of 2011 MD were to enter Earth's atmosphere, it would be expected to burn up high in the atmosphere and cause no damage to Earth's surface, said JPL.The accompanying diagram gives a view of the asteroid's trajectory from the general direction of the Sun. This view indicates that 2011 MD will reach its closest Earth approach point in extreme southern latitudes (in fact over the southern Atlantic Ocean), according to JPL. The incoming trajectory leg passes several thousand kilometers outside the geosynchronous ring of satellites and the outgoing leg passes well inside the ring, JPL said.For a brief time, it may be bright enough to be seen even with a modest-sized telescope.One would expect an object of this size to come this close to Earth about every six years on average.The asteroid was discovered by the LINEAR near-Earth object discovery team observing from Socorro, New Mexico.

CANBERRA, Sept. 7 (Xinhua) -- A team of Australian and U.S. scientists on Wednesday said they discovered a genetic defect, which can lead to Leigh syndrome, a rare disorder which affects the central nervous syndrome.The scientists tested more than 1000 genes by encoding proteins active in two individuals who suffer from the illness. They used a new technique known as next-generation DNA sequencing to examine the genes.The gene they discovered encodes an enzyme which is found in the mitochondria which are subsets of cells. Without this enzyme the mitochondria do not translate proteins efficiently, and this then causes Leigh syndrome.According to David Thorburn, from the Murdoch Children's Research Institute in Melbourne, the discovery shows the enormous potential of the new technology."These findings demonstrate the ability of sequencing technologies to improve diagnosis," Professor Thorburn said in a statement released on Wednesday."Although it isn't clear in the case of Leigh syndrome whether the precise molecular diagnosis will necessarily lead to therapies, the current findings represent a meaningful service."He added that diagnosis of the disease along with its specific genetic cause can also be informative about the risk a couple has of having another affected child. The diagnostic information can help in decisions about whether and how to pursue alternative means of having children, for instance through the use of donor sperm or eggs.The research team consisted of scientists from Australia's Murdoch Institute as well as the Broad Institute in the U.S.In Leigh syndrome, infants are born apparently healthy only to develop movement and breathing disorders that worsen over time, often leading to death by the age of three. The problem is that the mitochondria responsible for powering their cells cannot keep up with the demand for energy in their developing brains.

WASHINGTON, June 23 (Xinhua) -- NASA's next Mars rover has completed the journey from its California birthplace to Florida in preparation for launch this fall, the U.S. space agency said Thursday in a statement.The Mars Science Laboratory (MSL) rover, also known as Curiosity, arrived Wednesday at NASA's Kennedy Space Center aboard an Air Force C-17 transport plane. It was accompanied by the rocket-powered descent stage that will fly the rover during the final moments before landing on Mars.The rover's aeroshell -- the protective covering for the trip to the Red Planet -- and the cruise stage, which will guide it to Mars, arrived at Kennedy last month. The mission is targeted to launch from Cape Canaveral Air Force Station between Nov. 25 and Dec. 18. The car-size rover will land on Mars in August 2012.The rover and other spacecraft components will undergo more testing before mission staff stack them and fuel the onboard propulsion systems. Curiosity should be enclosed in its aeroshell for the final time in September and delivered to Kennedy's Launch Complex 41 in early November for integration with a United Launch Alliance Atlas V rocket.Curiosity is about twice as long and more than five times as heavy as any previous Mars rover. Its 10 science instruments include two for ingesting and analyzing samples of powdered rock delivered by the rover's robotic arm. During a prime mission lasting one Martian year -- nearly two Earth years -- researchers will use the rover's tools to study whether the landing region has had environmental conditions favorable for supporting microbial life and favorable for preserving clues about whether life existed.

BUJUMBURA, May 31(Xinhua) -- As the World No Tobacco Day is celebrated on Tuesday, many Burundians feel happy that they have given up smoking thanks to herbal drugs.Evariste Ndikumwami, 55, residing in the Burundian capital Bujumbura, said he had been smoking for 30 years, but gave up smoking in January after taking herbal drugs prescribed by an abbot."I had been smoking since my teenage and I gave up smoking in January (this year) after I took herbal drugs that I got from a Roman Catholic priest from Uganda working at Rugari parish in the province of Muyinga, some 210 km northeast of the Burundian capital Bujumbura," Ndikumwami told Xinhua.Ndikumwami said he used to smoke a pack of 20 cigarettes per day, adding that he had found it hard to give up smoking.He said, "I took the herbal drugs for 15 days. The abbot prescribed me two herbal drugs -- one to be smoked for five days at daytime when I desire to smoke and another one to be applied around the nostrils at night."After the medication period, he never felt the desire for smoking cigarettes, he said."When my friends realized I was no longer smoking, they asked me which drugs I took to give up smoking. I directed them to the abbot who had healed me and they also got cured and stopped smoking," Ndikumwami said.

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