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Astronauts make 3rd Hubble repair look easyMay 17, 2009 (The Orlando Sentinel - McClatchy-Tribune Information Services via COMTEX) -- CAPE CANAVERAL -- It was advertised as the hardest job of Atlantis' 11-day mission to repair and upgrade the Hubble Space Telescope. Instead it looked like the easiest. In an amazingly successful 6-hour, 36-minute spacewalk, astronauts John Grunsfeld and Andrew "Drew" Feustel managed to perform the equivalent of cosmic brain surgery, cutting into sensitive electronic instruments never designed to be opened and tinkered with by gloved hands in the vacuum of space. The two had practiced for more than a year on mockups in a giant swimming pool to get ready for the delicate operation to repair the Advanced Camera for Surveys. Once the workhorse of the telescope, responsible for many of the observatory's famous images, the camera's electronics had shorted out two years ago. But repairs on an instrument's electronic innards had never been attempted before by spacewalking astronauts. "Putting in new instruments is bad enough," Ed Weiler, NASA's associate administrator for science missions, said after Atlantis launched Monday. "But taking things apart and putting in circuit boards when you are an astronaut wearing gloves, it's a little dicey." Grunsfeld -- nicknamed the "Hubble-Hugger" because he is a veteran of two previous Hubble-servicing missions -- had to remove dozens of tiny screws and cut through a metal cover to pull four fried circuit boards from the survey camera. It was fussy, meticulous work. At one point, he was pulling and replacing tools from his bag like an interstellar lineman with a high-tech tool belt on the ultimate galactic cherry picker, 350 miles above the Earth. Each twist and turn of Grunsfeld's cosmic surgery was beamed down to Earth from a camera on his helmet. Grunsfeld did not actually grab the circuit boards with his gloved hands. The edges of the boards were too sharp and could have punctured his pressurized suit. So instead he used a clamp and slid each board out by turning a knob. After replacing the boards, he spliced in an electrical cable and connected it to a new low-voltage power supply that replaced one destroyed in 2007 by a catastrophic short circuit. The improbable repair job went so smoothly that ground engineers were caught by surprise. It was even better when tests showed the repaired unit was working. "Woo-hoo!" Feustel called out. "Oh, that's unbelievable," Grunsfeld said. "Believable," exclaimed Feustel. It was at least work with a view. At one point in the middle of the tasks, Feustel look up and shouted: "I can see Hawaii!" This was the third spacewalk of the five back-to-back planned to upgrade Hubble. The previous two were not as smooth, and Friday's nearly eight-hour walk became the eighth longest on NASA's record because astronauts had trouble getting new gyroscopes to fit on the telescope. But after Saturday's spacewalk, an elated Preston Burch, NASA's Hubble program manager at the Goddard Space Flight Center in Greenbelt, Md., told reporters that with two thirds of the repair mission done, Hubble is better than ever before. "John Grunsfeld and Drew Feustel just made it look so easy out there," he said. Robert Block can be reached at [email protected] or 321-639-0522. To see more of The Orlando Sentinel or to subscribe to the newspaper, go to http://www.OrlandoSentinel.com. Copyright (c) 2009, The Orlando Sentinel, Fla. Distributed by McClatchy-Tribune Information Services. For reprints, email [email protected], call 800-374-7985 or 847-635-6550, send a fax to 847-635-6968, or write to The Permissions Group Inc., 1247 Milwaukee Ave., Suite 303, Glenview, IL 60025, USA. |