An asteroid about half the size of a football field will pass so
near Earth during Friday's lunch hour that it will be closer
than many communication and television satellites. The hunk of
rock that is about 150 feet in diameter with a mass of about
140,000 tons has no chance of hitting the planet, but it's the
closest object of its size to pass by Earth that researchers
knew of in advance since they began scanning the skies in the
early 1990s. The asteroid, whose name of 2012 DA14 doesn't quite
capture the excitement surrounding it, will be 17,200 miles from
the Earth at 12:45 p.m. MST. Communication satellites orbit at
about 22,000 miles out, and GPS satellites are about 11,000
miles out. Seth Jarvis, director of the Clark Planetarium and a
NASA Solar System Ambassador to Earth, said he hopes people will
look at this asteroid's flyby as a "teachable moment" to
understand the potential danger near-Earth objects pose. "This
asteroid is one of about 1,400 potentially hazardous asteroids
being tracked by NASA,