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        1. Intermediate-sized near-Earth asteroid to fly safely past Earth next month

          Source: Xinhua| 2018-01-20 16:20:57|Editor: pengying
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          LOS ANGELES, Jan. 19 (Xinhua) -- An intermediate-sized near-Earth asteroid will make a close approach to the Earth on Feb. 4, but it will have no chance of colliding with our planet, the U.S. National Aeronautics and Space Administration (NASA) said Friday.

          At the time of closest approach, the asteroid will be no closer than 10 times the distance between Earth and the Moon, said a press release from NASA.

          Known as 2002 AJ129, the asteroid is categorized as a Potentially Hazardous Asteroid (PHA), which is defined by NASA as Near-Earth Asteroids "with an Earth Minimum Orbit Intersection Distance (MOID) of 0.05 astronomical units or less and an absolute magnitude of 22.0 or less."

          But 2002 AJ129 does not pose an actual threat of colliding with our planet for the foreseeable future. It is one of over 1,000 asteroids and comets scientists currently know about that falls under the PHA category.

          "We have been tracking this asteroid for over 14 years and know its orbit very accurately," Paul Chodas, manager of NASA's Center for Near-Earth Object Studies at the Jet Propulsion Laboratory, was quoted as saying by the news release. "Our calculations indicate that asteroid 2002 AJ129 has no chance - zero - of colliding with Earth on Feb. 4 or any time over the next 100 years."

          The rock is somewhere between 0.5 km and 1.2 km in width - by comparison, Burj Khalifa, the world's tallest building in Dubai, United Arab Emirates, is about 0.82 km tall.

          The asteroid was discovered on Jan. 15, 2002, by the former NASA-sponsored Near Earth Asteroid Tracking project at the Maui Space Surveillance Site on Haleakala, Hawaii. It will make a close approach to Earth on Feb. 4. at 1:30 p.m. PST (2030 GMT) within about 4.2 million km.

          The asteroid's velocity at the time of closest approach, 34 km per second, is higher than the majority of near-Earth objects during an Earth flyby.

          The high flyby velocity is a result of the asteroid's orbit, which approaches very close to the Sun -- 18 million km.

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