In 1959, the Soviet Union sent the first spacecraft to impact the moon's surface and returned the first photographs of its far side. In 1969, the United States landed the first astronauts on the moon, undoubtedly the most famous of NASA's achievements, followed by five more successful missions (and one, Apollo 13, that didn't make to the moon). Their efforts returned 842 pounds (382 kg) of rocks and soil to Earth for study. It remains the only extraterrestrial body that humanity has ever visited.