The Hubble Space Telescope has received its last upgrades and repairs. The fifth and final spacewalk of the last shuttle mission to Hubble ended at 3:22 P.M. (Eastern Daylight Time), wrapping up an ambitious and remarkably successful servicing operation.

The Hubble team hopes that the fixes will keep the telescope alive for several years, maybe even a decade or more, long after the space shuttle's scheduled retirement next year.

In today's spacewalk, the third of this mission for Drew Feustel and John Grunsfeld, the astronauts replaced three of Hubble's six massive batteries, which have powered the spacecraft during the night portion of its orbit for all of its 19 years in space. (The other three were swapped out in an earlier spacewalk.) Feustel and Grunsfeld also replaced a faulty Fine Guidance Sensor, one of three that helps to point the telescope, and installed a new set of external thermal blankets.

In earlier sojourns, the Atlantis crew installed two new science instruments, replaced a hobbled data router, and repaired two existing instruments, a camera and a spectrograph, that had suffered electronic failures.

The spacewalkers encountered myriad snags throughout the mission, from stuck bolts to new parts that just wouldn't fit right. "Given all of these difficulties, I'm astonished that we've achieved essentially everything we have set out to do up to this point," said David Leckrone, senior Hubble project scientist at the NASA Goddard Space Flight Center in Greenbelt, Md., as the final spacewalk was under way. "I have to pinch myself to realize I'm not dreaming when I think that all of our instrument work has been successful, and especially that both repaired instruments are working once again after years of being dormant."

Feustel and Grunsfeld near the completion of their spacewalk today: NASA TV