HD 80606b is a gas giant planet in an eccentric orbit around its star. Every 111 days, the planet passes within 2.8 million miles of the star's surface. During the close approach of Nov. 20, 2007, NASA's Spitzer Space Telescope observed the system for 30 hours. Scientists modeled the response of the planet's upper atmosphere to the extreme heating. The animation based on their simulations begins 4.4 days after closest approach, when the hot hemisphere has rotated into view. A massive storm has formed in response to the pulse of heat delivered during the planet's close swing past its star. Successive frames, spaced every 12 hours, show the hot spot rotating out of view. The Spitzer observations represent the first time astronomers have detected weather changes in real time on a planet outside our solar system.