Asteroid makes close approach to Earth early Thursday

Last night as many of us were sleeping, an asteroid around the size of a school bus made a closer appearance than most of its size usually do.

The asteroid, known as 2012 TC4, traveling around 30,000 mph did not enter the Earth's atmosphere, but it was close enough to be seen by small telescopes. South Dakota Space Grant Consortium Deputy Director Tom Durkin says even asteroids this large usually do not threaten the planet.

SD Space Grant Consortium Deputy Director Tom Durkin says, "Each time it comes by Earth, it passes very closely now. It missed us by only about 26,000 miles. Roughly, that's just about three Earth diameters, so it was well within the moon's orbit at about a quarter million miles away. So it was very, very close. So if it was a large asteroid, it would be something to be more concerned about, but even if it had entered the Earth's atmosphere last night, it likely would've burned up before it struck the Earth. It was small enough for that."

Asteroids this size enter the atmosphere around once per year, and can be seen as a bright flash in the sky as the rock is being vaporized.