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BEIJING, Oct. 23 (Xinhuanet) -- By analyzing sunlight reflected from its surface, scientists say the asteroid Apophis -- which has a slight chance of colliding with Earth -- is a "good match for a rare type of stony meteorite known as type LL chondrite. Meteorites with this mineral composition represent just 7 percent of the known space rocks that plunge to Earth. The finding, presented last week at an annual meeting of the Division for Planetary Sciences of the American Astronomical Society, could be useful in planning future missions to explore Apophis or in protecting Earth from a future impact. "Basic characterization is the first line of defense," said study team member Richard Binzel of MIT. "We've got to know the enemy." Apophis' composition is similar to that of Itokawa, the asteroid visited by the Japanese Hayabusa mission, Binzel told SPACE.com. Apophis is currently about 158 million miles (254 million kilometers) from Earth and will not be visible again for several years. On April 13, 2029, it will pass within 22,000 miles (35,000 kilometers) of Earth, but there is about one chance in 45,000-that it could be on a collision course with our planet when it comes by again in 2036. (Agencies)
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