S125-E-009721 (18 May 2009) --- Astronauts John Grunsfeld (left) and Andrew Feustel, both STS-125 mission specialists, participate in the mission?s fifth and final session of extravehicular activity (EVA) as work continues to refurbish and upgrade the Hubble Space Telescope. During the seven-hour and two-minute spacewalk, Grunsfeld and Feustel installed a battery group replacement, removed and replaced a Fine Guidance Sensor and three thermal blankets (NOBL) protecting Hubble?s electronics.