High Quality Content by WIKIPEDIA articles! Skylab 3 (also SL-3 and SLM-2) was the second manned mission to Skylab. The Skylab 3 mission started July 28, 1973, with the launch of three astronauts on the Saturn IB rocket, and lasted 59 days, 11 hours and 9 minutes. A total of 1,084.7 astronaut-utilization hours were tallied by Skylab 3 astronauts performing scientific experiments in the areas of medical activities, solar observations, Earth resources and other experiments.