April 22, 2008 11:05 AM PDT
From the first look at the Earth from outer space, NASA has been watching our planet and how man has affected it. For Earth Day, NASA has compiled some of its most breathtaking views of Earth, including some "firsts," natural and man-made disasters, and out-of-this-world sights.
On April 1, 1960, the weather satellite Tiros-1 took its first image of Earth.
For more Earth Day coverage, see CNET News.com's special feature and a gallery of NASA's top 10 photos of Earth taken by astronauts from the International Space Station.
Photo by NASA
