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NOVA scienceNOW: Asteroid

Program Overview

Scientists discuss the chances of Apophis, an asteroid detected in 2004, hitting Earth. They consider the consequences of such an impact, and how people might prevent or prepare for catastrophic damage from a powerful asteroid strike.

This NOVA scienceNOW segment:

• reports that, although early analysis suggested that the asteroid might hit Earth in 2029, this collision will not happen, though Apophis will pass within 20,000 miles of Earth.

• describes Apophis as 1,000 feet wide (bigger than the Rose Bowl) and that a collision with the asteroid would have the energy of 100 nuclear bombs exploding at the same time.

• notes examples of past asteroid impacts and describes how NASA hunts for asteroids and estimates the odds of a collision with Earth.

• defines the keyhole, a small region of space that, if an asteroid passes through, increases to 100 percent the possibility that the asteroid will hit Earth the next time it approaches.

• states that the area between the planets is filled with debris, ranging in size from small sand grains to large asteroids.

• explains how it may be possible to prevent an asteroid collision by slowing down or speeding up an asteroid.

Taping Rights: Can be used up to one year after the program is taped off the air.