Skylab The Second Manned Mission Introduced by Astronaut Rusty Schweickart Skylab 2 would turn into a repair mission making way for Skylab 3's exciting scientific discoveries. Human and animal reactions to zero gravity were studied using live minnows and spiders. Numerous physiological studies were conducted on the astronauts. Also, an Apollo telescope recorded never before seen shots of the sun. Skylab provided further information about our own planet's pollution, crop diseases, erosion and land use. It was a triumph of human intelligence. And, even more important, a gateway to more.