A 400-metre-wide asteroid will Tuesday fly past earth, closer to it than the moon's orbit. The asteroid will pose no threat to Earth, NASA says. It will not be visible without a telescope.
http://ummid.com/news/2011/November/08.11.2011/asteroid_to_pass_today.htm
http://ummid.com/news/2011/November/08.11.2011/asteroid_to_pass_today.htm