Spacewalking astronauts repaired and upgraded the famed Hubble Telescope during five missions from 1993 to 2009. Here's a summary of these epic servicing efforts.

Fixing the Hubble Space Telescope: A timeline of NASA's shuttle servicing missions

Source: space
Source Link: https://www.space.com/space-exploration/hubble-space-telescope/fixing-the-hubble-space-telescope-a-timeline-of-nasas-shuttle-servicing-missions