by PATRICK LEJTENYI

Even the most sophisticated, deepest- and furthest-looking eye in the sky, NASA's Hubble Telescope, isn't immune from obsolescence. Until last spring, smart money had the massive piece of machinery breaking down in late 2007 or 2008, its 18 years of orbit and staggering scientific accomplishments concluding in a fiery cascade through the upper atmosphere.

That is, until early June, when NASA bigwigs opened a call for proposals on a robotic mission to save the popular stargazer. By mid-last week, odds looked good that the robot to the rescue would be one designed by Canadians - Brampton, Ontario's MacDonald Dettwiler Robotics, the company that brought us such showcase pieces as the Canadarm and Canadarm2, working closely with the Canadian Space Agency (CSA), based across the river from Montreal in St-Hubert.

The as-yet-unfinished dual-armed robot, called Dextre (as in dexterous), is in its final testing phase before its scheduled 2007 launch to the International Space Station. If given the go-ahead, says the CSA's director-general of space programs Savi Sachdev, a new Dextre could be built to repair the Hubble a couple of years afterwards.

For safety reasons, NASA doesn't want to send humans into space via shuttle any time soon. Therefore, Dextre would be launched on either an Atlas V or Delta IV rocket until it separates and is attached to another vehicle with a 32-foot-long arm. From there it would reach the Hubble to carry out much-needed repairs and improvements.

"We will be using the new robot differently," says Sachdev. "The challenge is manipulating it to carry out fine dexterous tasks that we had not really envisaged using on the space station, where everything is reasonably well-structured." He also says that because the mission will be controlled from Earth using telerobotics, there will be a two-second delay between command and execution.

Dextre's shape looks remotely human: it has a rotating central torso with two 10-foot-long arms, each with seven joints, attached at the shoulder. Both arms feature a hand-like appendage that can grip objects with parallel retractable jaws. And while its original design was based on moving heavy payloads outside the station, the Hubble mission requires a more delicate touch.

"Basically it will be carrying out repairs," says Sachdev. "Things like attaching connectors, wiring and cable harnesses, as well as installing two new cameras." It will also replace the telescope's failing gyroscopes, which direct its vision, and its spectrograph, used to detect images with ultraviolet sources. It's hoped that a successful mission will extend Hubble's life by an extra four or five years, until NASA's next big satellite, the James Webb, is launched in 2011 or 2012 (the Webb will supposedly be able to look back 14.5-billion years, to "First Light," the very first galaxies formed after the Big Bang. Hubble can only see back 10-billion years). "If Hubble dies in 2007, we'll lose four or five years of viewing," says Sachdev.

NASA has yet to determine if and when a Hubble rescue mission will be launched, and if Dextre will even be on board. However, if the announcement is going to come, it'll have to come soon. Sachdev says that it will take two to three years to build another $350-million Dextre, and Hubble's days in space are numbered.