'While we have done radar observations on this particular asteroid before, this is the closest it has come since at least the twelfth century,' said Dr. Steve Ostro, a scientist at JPL. 'We will use the huge dish in Arecibo, Puerto Rico, to refine our knowledge of its physical characteristics and its trajectory.' Named after an obscure Celtic and Gallic god, Toutatis is a yam-shaped space rock that measures 1.92 kilometers (1.2 miles) by 2.29 kilometers (1.4 miles) by 4.6 kilometers (2.9 miles). Toutatis has one of the strangest rotation states observed in the solar system. Instead of spinning around a single axis, as do the planets and the vast majority of asteroids, it 'tumbles' somewhat like a football after a botched pass. Its rotation is the result of two different types of motion with periods of 5.4 and 7.3 Earth days, which combine in such a way that Toutatis's orientation, with respect to the solar system, never repeats.
When the asteroid flew past Earth, it was traveling at approximately 39,600 kilometers per hour (24,550 miles per hour). Toutatis will not be this close again until 2562. It was discovered in 1989.