Two NASA astronauts are back inside shuttle Atlantis after a wildly successful mission to outfit the Hubble Space Telescope with new state-of-the-art spectrograph and repair a broken planetary camera.
Atlantis lead spacewalker John Grunsfeld and mission specialist Andrew "Drew" Feustel removed Hubble's 16-year-old "contact lenses" and replaced it with a super-sensitive spectrogragh that will shed new light on mysterious dark matter that makes up 90 percent of the universe.
On the third of five spacewalks scheduled on consecutive days, the astronauts also revived the Advanced Camera for Surveys, a powerful planetary camera that suffered serious electrical failures that shut down two of its three channels.
Grunsfeld and Feustel were stoked when Mission Control reported that the near-comatose camera had been successfully resuscitated.
"Woo-hoo!" Feustel called out.
"Oh, that's unbelievable," Grunsfeld said.
"Believable," said Feustel.
"Nice work, guys," Atlantis mission commander Scott Altman said. "Congratulations to you, John, and Drew, for a great effort."
The astronauts switched off battery power to their spacesuits and begin pressurizing the shuttle's external airlock at 4:11 a.m., officially marking the end of a 6-hour, 36-minute excursion.
It was the 21st Hubble servicing spacewalk performed since the observatory was launched into orbit in April 1990. Astronauts now have tallied 151 hours and two minutes of spacewalking work on the observatory since NASA's first Hubble repair mission in December 1993.
Atlantis mission specialists Mike Massimino and Mike Good will venture outside Atlantis on Sunday for the fourth spacewalk of the STS-125 mission. Their big challenge: Repair the Space Telescope Imaging Spectrograph.
You can watch all the action unfold here in The Flame Trench. Simply click the NASA TV box on the righthand side of this page to launch our NASA TV viewer and live 24/7 coverage of the STS-125 mission.
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