ASTEROID TO BUZZ EARTH TONIGHT: House-sized asteroid 2012 TC4 is approaching Earth today for a close encounter only 1/8th the distance to the Moon. At closest approach, the space rock will skim just outside Earth’s zone of geosynchronous communications satellites and be visible in telescopes as small as 8-inches (observing tips). Alberto Quijano Vodniza, of Pasto, Colombia, made this movie of the faint asteroid moving among the stars on Oct. 11th:
There’s no chance of a collision. “We know the orbit of 2012 TC4 well enough to be absolutely certain that it won’t hit Earth,” says Paul Chodas, manager of the Center for Near-Earth Object Studies at JPL,”but we haven’t established its exact path just yet.”
To get a better handle on the asteroid’s orbit (and possible future encounters), an international network of telescopes will monitor 2012 TC4 as it goes by. Pinging the asteroid with its Goldstone radar, NASA hopes to learn much about the space rock’s physical properties. The space agency will even exercise some aspects of its planetary defense systems.
Asteroids of this size are numerous in the solar system, and Earth is a frequent target. The last time an asteroid akin to 2012 TC4 hit Earth was barely more than 4 years ago. On Feb. 15, 2013, a previously undiscovered asteroid ripped through the atmosphere over Chelyabinsk, Russia. Shock waves knocked onlookers off their feet and shattered windows in hundreds of buildings. Years later, meteorite hunters are still finding pieces of the “Chelyabinsk asteroid” that rained down after its 17m-wide body disintegrated in the atmosphere.