The asteroid, called 4179 Toutatis, is about 5.5 kilometers wide, and will approach our planet tonight to a distance of about 6.9 million kilometers. The distance is not close enough to pose a threat to Earth, and the celestial body is not large enough to be seen with the naked eye, but large astronomical telescopes
would be able to get a good look. The following websites
will broadcast the event live: Slooh Space Camera
and Virtual Telescope Project.
According to Slooh Space Camera
the best time to watch will be within about 5 hours from now (5 PM EST).