Spacelab was a reusable laboratory used on certain spaceflights flown by the Space Shuttle. The laboratory comprised multiple components, including a pressurized module, an unpressurized carrier and other related hardware housed in the Shuttle's cargo bay. The components were arranged in various configurations to meet the needs of each spaceflight.
Spacelab components flew on 22 Shuttle missions between November 1983 and April 1998. Spacelab allowed scientists to perform experiments in microgravity in Earth orbit.
The fifth dedicated Spacelab mission, Spacelab Life Sciences-1, and first mission dedicated solely to life sciences, using the habitable module. The mission featured the most detailed and interrelated physiological measurements in space since 1973-1974 Skylab missions. Subjects were humans, 30 rodents and thousands of tiny jellyfish. Primarily the SLS-1 experiments studied six body systems; of 18 investigations, ten involved humans, seven involved rodents, and one used jellyfish.
The six body systems investigated were cardiovascular/cardiopulmonary (heart, lungs and blood vessels); renal/endocrine (kidneys and hormone-secreting organs and glands); blood (blood plasma); immune system (white blood cells); musculoskeletal (muscles and bones); and neurovestibular (brains and nerves, eyes and inner ear). Other payloads included twelve Get Away Special (GAS) canisters installed on the GAS bridge in the cargo bay for experiments in materials science, plant biology and cosmic radiation; Middeck Zero-Gravity Dynamics Experiment (MODE); and seven Orbiter Experiments (OEX).