Power restored in space repairs

FOR the second straight day, astronauts stepped out on a space walk yesterday to bring a scientific instrument back from the dead on the Hubble Space Telescope.

This time, the work involved removing 117 screws, all but six of them tiny enough to slip through the fingers. It was expected to be much harder for spacewalker Michael Massimino because of his bulky gloves.

Massimino and Michael Good ventured out as space shuttle Atlantis sailed 560km above Australia. They began working on the Space Telescope Imaging Spectrograph, disabled by a power failure five years ago.

On Saturday, two other astronauts – Andrew Feustel and John Grunsfeld – succeeded with a similar task and revived Hubble’s survey camera. Early yesterday, Mission Control told the crew that testing had confirmed two of the science channels on the repaired camera were working again. A third was not.

But the wide-field channel that was resuscitated is “the real workhorse” and carries 95% of the science output, Mission Control noted.

“Fantastic! Power is restored,” said astronaut John Grunsfeld, the chief Hubble handyman who made the camera repairs.

NASA officials hoped yesterday’s space walk would be just as successful. Neither the surveys camera nor imaging spectrograph was designed to be repaired in orbit, so NASA had to design dozens of special tools.

This was the fourth space walk for the Atlantis astronauts, leaving just one more before it’s time to set the better-than-ever Hubble free.

No further repair missions are planned for the 19-year-old observatory.

Flying so high without an emergency shelter put the shuttle and astronauts at increased risk of being hit by space debris, so NASA had another shuttle on standby back at its Florida launching site in case a rescue was needed.

Besides the spectrograph work, Massimino and Good planned to install some new insulation on the telescope. The spacewalkers had a specially designed roller tool to apply the stainless steel foil covers, which look like large cookie sheets.

When NASA planned this mission, officials said it would be a success if either of the two dead instruments could be revived. With Saturday’s camera remedy, fixing the spectrograph would be a bonus.