Kerwin examining Conrad on Skylab 2, 1973. Skylab 2 commander Pete Conrad undergoes a dental examination by medical officer Joseph Kerwin in zero gravity. In the absence of an examination chair, Conrad rotated his body to an upside down position to facilitate the procedure. The Skylab space station, first launched in May 1973, and was occupied in succession by three teams of three crewmembers. These crews orbited the Earth and performed nearly 300 experiments.