Talk about dazzling fireworks. On July 4, NASA’s Deep Impact spacecraft flew itself into the path of an oncoming comet speeding at 23,000 miles an hour. The resulting collision created a spectacular flash of light that was photographed by the craft’s flyby mothership. The mission, the first to crack open a comet, should turn up new clues to the evolution of the solar system and tell us what role comets play in carrying life-supporting chemicals to Earth.
Check out our illustration for a blow-by-blow account of the collision:
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Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.