... Skylab Over Earth . ... Skylab was an orbiting laboratory launched by a Saturn V rocket in May 1973. Skylab was visited three times by NASA astronauts who sometimes stayed as long as two and a half months. ... Saturn V: NASA's Largest Rocket . ... The Saturn V rocket was the largest rocket ever used by NASA, and the only one able to lift the large masses needed to land astronauts on the moon and returning them safely. ... Two Tails of Comet West . ... NASA.. A Radar Image of Planet Earth . ...