Atlantis conducted the final servicing mission to the Hubble Space Telescope. Its STS-125 mission, also called Servicing Mission 4, launched on May 11, 2009, and concluded Hubble’s planned series of shuttle servicing visits.
Atlantis carried seven astronauts, who captured Hubble and performed five spacewalks over nearly 13 days. They installed two new scientific instruments, repaired two others, replaced batteries and gyroscopes, and added insulation panels. These upgrades significantly extended the observatory’s useful life and improved its ability to study the universe.
The mission was delayed after a Hubble electronics failure required NASA to redesign the servicing plan. Endeavour stood ready as a potential rescue vehicle while Atlantis carried out the mission. The shuttle returned to Earth on May 24, 2009, landing at Edwards Air Force Base.
A common mix-up is confusing Atlantis with Discovery, which deployed Hubble in 1990 and later serviced it. Atlantis performed the fifth and final servicing mission; no later shuttle mission visited Hubble.