Fifty years ago today, the Soviet Union launched Sputnik I, the world’s first artificial satellite. That launch on Oct. 4, 1957 marked the start of the Space Age and the U.S.-Soviet space race.
Sputnik was the size of a basketball and only weighed 183 pounds, but it took the American people by surprise and jolted the nation into action. By 1958, NASA was formed, and a decade later, the first Americans walked on the moon.
To celebrate the start of the Space Age, NASA has created a great interactive website with video footage, 3D models of Sputnik and the U.S.’s Explorer I, and interesting photos.