There's no need to worry about calling Bruce Willis and Ben Affleck to blow this one up, but it should be pretty cool to watch this huge asteroid pass by earth today.

The asteroid 2004 BL86 will do a fly by of Earth at about 1.2 million kilometers, or three times the distance of the moon.  There have been asteroids in recent history that have flown closer to earth, but the size of this one makes it special.

The problem is that we won't be able to see it with the naked eye.  You do have some options though, including a normal telescope or some high powered binoculars.

The best option though is a live stream of the fly by provided by slooh.com.

So what would happen if this giant slammed into earth?  Bad things . . . aside from the 8 mile crater it would leave, the impact winter, acid rain and firestorms it would cause would make it a bad day.

The asteroid live stream will start right around 11AM today, and you can watch the live stream from Slooh below.