At just 30 years old, golf professional Tiger Woods won the 50th PGA, making him the youngest person ever to win a PGA.
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Pittsburgh hosted the world's largest pinball tournament.
The Department of Health in Manila, Philippines, declared a national epidemic after the dengue outbreak.
A team of NASA scientists declared that the Martian ALH 84001 meteorite might contain traces of alien life.
NASA's Curiosity rover landed on Mars' Aeolis Palus plain.
Jon Stewart hosted his last episode of 'The Daily Show.'