Space shuttle Columbia lifted off from Kennedy Space Center in Cape Canaveral, Fla., this morning, on a mission to repair the Hubble Space Telescope.

After a one-day wait for warmer launch weather, Columbia vaulted into clouds just before dawn as Hubble was passing nearly overhead. The 350-mile-high chase should end Sunday.

``Hubble's up there ready for us and we're ready to go to work,'' shuttle commander Scott Altman called out.

The launch was surrounded by extraordinarily tight security to guard against possible terrorist attack. F-15 fighter jets were on patrol, and a no-fly zone was in force within 35 miles of the launch pad.

Altman waved as he and his crew boarded the heavily guarded van for the middle-of-the-night ride to the pad. ``The crowd goes wild, hey!'' Altman shouted. The crowd, while enthusiastic, consisted of just 25 space center employees, fewer than usual because of security concerns.

It was balmier than Thursday morning, when near-freezing temperatures forced a one-day delay. The mercury was up to 60 for Friday's try.

``We wish you good luck on this very important mission to the Hubble Space Telescope and you all have fun up there,'' launch director Mike Leinbach told the astronauts just before Columbia's 6:22 a.m. liftoff.

The rising sun painted Columbia's contrail pink, peach and white. NASA's space science chief, Ed Weiler, compared it to the remnants of an exploded star. ``Now, that's a good omen,'' he said.

Launch observers could see the rising shuttle for as long as seven minutes and the twin booster rockets falling almost all the way to splashdown. Even the Hubble was visible as a bright star.

NASA's oldest shuttle, fresh from a massive overhaul, had a perfect start to its 11-day flight. ``It's been two years and seven months since Columbia last flew,'' noted shuttle manager James Halsell. ``It got onto orbit without even as much as a minor fault message, much less any type of major alarm.''

Columbia is loaded with $172 million worth of scientific, power and steering parts for Hubble.

The astronauts will conduct a record-tying five spacewalks next week to install all the equipment on the 12-year-old telescope. The parts include stronger solar wings, more robust power-control unit, more reliable steering mechanism, refrigeration system to resuscitate a disabled infrared camera, and advanced camera to increase Hubble's capability for discovery by 10 times.

NASA considers this the most complicated Hubble servicing mission yet because of the heavy workload and a pair of unprecedented spacewalking jobs. Neither the power-control unit nor infrared camera repairs were meant to be tackled in orbit.

Before the old power-control unit can be removed and the new one installed, all of Hubble's systems must be turned off for the first time ever in orbit. Scientists are understandably nervous, even scared. But they say there is a greater chance that the current power unit will eventually fail than there is that the telescope, or even a major portion of it, will not come back on following the repairs.

This is NASA's fourth visit to Hubble, considered by many to be the world's greatest telescope. The first service call, in 1993, corrected the telescope's blurred vision.

One more servicing mission is planned after this one, in 2004. Then if NASA has its way, the telescope will be returned to Earth in 2010 for museum display.

Columbia is due back on March 12.