STS-61 was the first Hubble Space Telescope servicing mission. Three primary objectives were successfully completed during a record-breaking five extravehicular activities (EVAs). These were to restore the planned scientific capabilities, to restore reliability of Hubble's systems and to validate the Hubble Space Telescope on-orbit servicing concept.
Life Sciences experiments performed during this mission included multiple Detailed Supplementary Objectives (DSOs). A DSO is a NASA-sponsored investigation performed by Space Shuttle crewmembers, who also serve as the test subjects. These studies require minimal crew time, power and stowage. Biomedical DSOs focus on operational concerns, including space motion sickness, cardiovascular deconditioning, muscle loss, changes in coordination and balance strategies, radiation exposure, pharmacokinetics and changes in the body's biochemistry.
Other payloads carried on board STS-61 were the IMAX Cargo Bay Camera, IMAX In-Cabin Camera, and the Air Force Maui Optical Site experiment.
The Shuttle Endeavour touched down after a successful 10.5-day mission at Kennedy Space Center on December 13, 1993.