NASA managers today decided to stick with Oct. 8 as the target launch date for shuttle mission STS-125, a long-awaited flight by the shuttle Atlantis to service and upgrade the Hubble Space Telescope. They also agreed to stick with Nov. 10 for launch of the flight after that, a space station assembly mission by the shuttle Endeavour.

As it now stands, Atlantis will be hauled to launch pad 39A on Aug. 26. Commander Scott Altman and his six crewmates - pilot Gregory C. Johnson, robot arm operator Megan McArthur and spacewalkers John Grunsfeld, Michael Massimino, Andrew Feustel and Michael Good - plan to strap in for a dress-rehearsal countdown on Sept. 19.

If all goes well, Atlantis will blast off around 1:34:49 a.m. on Oct. 8. After grappling the space telescope, the first of five back-to-back spacewalks will begin around 6:50 p.m. on Oct. 10 to install two new instruments, an upgraded fine guidance sensor, a new set of batteries and full set of gyroscopes. The astronauts also will attempt to repair two instruments that malfunctioned earlier and install fresh insulation. The flight plan calls for the astronauts to release the refurbished telescope on Oct. 15 and to land back at the Kennedy Space Center around 10:30 p.m. on Oct. 18.

STS-125 had been targeted for launch Aug. 28, but in May the flight was delayed because of time needed to ready two external fuel tanks. The Hubble repair crew cannot seek "safe haven" aboard the international space station if a Columbia-class heat-shield problem occurs. As a result, NASA Administrator Mike Griffin decided early on to have a second shuttle - Endeavour - prepped for launch on a rescue mission if necessary. Assuming no rescue flight is needed, Endeavour then would be used for the next station assembly mission, STS-126.

The Hubble rescue requirement meant two tanks had to be ready at roughly the same time and building new tanks with post-Columbia safety upgrades took a bit longer than initially expected. The Hubble launch slipped to Oct. 8 and Endeavour's flight was delayed from mid October to Nov. 10. A flight that had been planned for December slipped to February.

As it turned out, work to ready the next two tanks went smoothly and NASA managers recently asked engineers to look into the possibility of moving the next two flights up a few days, to Oct. 2 and Nov. 4 respectively. That later was amended to Oct. 5 and Nov. 7. Today, program managers agreed to stick with Oct. 8 and Nov. 10.

"It was a combination of things," a NASA spokesman said. "When they put that CR (launch date change request) out, they put it out with the understanding that tank processing needed to mature. They had to watch that for a while. That ended up turning out better than they hoped. The problem came with Hubble payload deliveries. Even if they hit every milestone they could possibly hit... the best they could do was Oct. 7."

The problem for Endeavour's flight was crew training. A tropical storm recently forced NASA to shut down the Johnson Space Center and Endeavour's crew lost valuable training time that could not be made up without violating work load guidelines. And so, the shuttle program decided to stick with the original Oct. 8 and Nov. 10 launch dates.

Additional coverage for subscribers:
VIDEO: BIOGRAPHY MOVIE OF ATLANTIS' CREW PLAY
VIDEO: INTERVIEW WITH COMMANDER SCOTT ALTMAN PLAY
VIDEO: INTERVIEW WITH PILOT GREG JOHNSON PLAY
VIDEO: INTERVIEW WITH MS1 MIKE GOOD PLAY
VIDEO: INTERVIEW WITH MS2 MEGAN MCARTHUR PLAY
VIDEO: INTERVIEW WITH MS3 JOHN GRUNSFELD PLAY
VIDEO: INTERVIEW WITH MS4 MIKE MASSIMINO PLAY
VIDEO: INTERVIEW WITH MS5 DREW FEUSTEL PLAY
MORE: STS-125 VIDEO COVERAGE
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