WASHINGTON, May 16 (Xinhua) -- A jumbo-jet-size asteroid made a close flyby of Earth on Tuesday at a distance of 203,000 km, the closest approach it made in at least two centuries.
According to the Minor Planet Center, a U.S. official body dealing with astrometric observations and orbits of minor planets (asteroids) and comets, the asteroid 2010 WC9 made its closest flyby at 2205 GMT while traveling at a speed of 12.8 km per second.
It flew no closer to Earth's surface than about 203,000 km, which is about half the distance between Earth and the Moon.
Invisible to the naked eye, it was observed through telescopes by astronomers with Tenagra Observatories in U.S. state of Arizona and The Virtual Telescope Project in Italy.
Astronomers estimated that 2010 WC9 is around 38 to 119 meters in diameter, as big as New York City's Statue of Liberty.
The asteroid was first spotted on Nov. 30, 2010, and tracked for about 10 days before astronomers failed to see it.
On May 8, stargazers once again discovered it and have been tracking its approach since then although its threat to Earth was already ruled out in 2010 based on orbit calculations.