People, not robots: panel favors shuttle mission to Hubble.

Sharply challenging NASA on the issue of safety in space, a National Academy of Sciences panel last week recommended that the space agency use astronauts to repair and upgrade the Hubble Space Telescope rather than send a robotic device under a plan that the agency has been promoting.

The academy committee, charged by Congress to study how to best and most safely service the 14-year-old orbiting Hubble observatory, concluded that there isn't enough time to develop a sophisticated, never-before-attempted robotic mission before Hubble's batteries are likely to give out in 2007. The robot would need to replace Hubble's batteries and gyros and possibly install new instruments. A hastily prepared robotic mission might even damage the telescope, the panel notes.

"The committee recommends that NASA pursue a shuttle servicing mission [to Hubble]," the report says. It adds that any robotic mission to Hubble should be used solely to move the observatory" out of its orbit at the end of its life, sometime around 2013.

A similar conclusion appears in the executive summary of a study from the nonprofit, El Segundo, Calif.-based Aerospace Corp., which provides services primarily to the Department of Defense. The corporation plans to deliver the full study to NASA late this week.

Last January, NASA Administrator Sean O'Keefe, who just announced his resignation, canceled the fifth and likely final shuttle mission to repair and upgrade Hubble. He cited safety, concerns after the demise of the Columbia space shuttle in 2003 (SN: 7/24/04, p. 56).

However, O'Keefe said that he would approve 25 to 30 missions to the International Space Station, once NASA lifts its moratorium on shuttle flights, because on those missions the crew could take refuge on the station if a problem arose on the shuttle.

"Our report is based on the fact that NASA and the nation have already accepted the risk of multiple human missions to the International Space Station," notes panel member Roger Tetrault, who was also a member of the Columbia investigation board. The academy panel found that "the additional safety risk of going to Hubble versus going to the space station is not significant," he adds. That's because, in either case, the highest risks unfold on launch and during reentry into Earth's atmosphere. Tetrault says that the panel believes that one more shuttle flight--to Hubble--is "worth the risk."

Some have speculated that O'Keefe's resignation might make it easier for NASA to accept the panel's conclusions. He's said repeatedly that his opposition to using the shuttle to repair Hubble is a personal decision based on concerns about risking astronauts' lives.

Steven Beckwith, director of the Baltimore-based Space Telescope Science Institute, which operates Hubble, says that he doesn't know anyone else for whom the shuttle question is "a personal decision."

Congressional hearings on the academy report are scheduled for early next year. "I'm tremendously optimistic about Hubble's future," Beckwith says. He notes that a new ultraviolet spectrograph and infrared camera have already been built and, if installed on Hubble, would further enhance the telescope's unparalleled vision.