Description: On the morning of February 15, 2013, a 7,000-ton asteroid crashed into the atmosphere of the Earth, exploded, and fell to the ground across a wide swath near the Ural Mountains in Russia. A blinding flash of light streaked across the sky, followed by a shuddering blast strong enough to damage buildings and send more than 1,000 people to the hospital. According to NASA, the Siberian meteor exploded with the power of 30 Hiroshima bombs and was the largest object to burst in the atmosphere since the Tunguska event of 1908-another impact in Siberia that left few eyewitnesses or clues. This time, the event was captured by digital dashboard cameras, now common in Russian autos and trucks. Within days, NOVA crews joined impact scientists in Russia as they hunted for clues about the origin and makeup of the meteor. Is our solar system a deadly celestial shooting gallery-with Earth in the crosshairs? And what are the chances that another, more massive asteroid is heading straight for us?