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![]() Countdown on schedule, weather forecast looks good BY WILLIAM HARWOOD STORY WRITTEN FOR CBS NEWS "SPACE PLACE" & USED WITH PERMISSION Posted: March 9, 2009 The shuttle Discovery's countdown to launch Wednesday is proceeding smoothly, officials said today, with no technical problems of any significance at the launch pad and excellent weather expected throughout the week. Forecasters are calling for a 90 percent chance of acceptable weather Wednesday and Thursday, decreasing slightly to 80 percent "go" on Friday. "The weather looks very good for launch, I'm very happy to say. Right now we're just looking at a really nice upper-level ridge that's been holding off the weather, the fronts that tend to come into the U.S. right now," said Kathy Winters, the shuttle weather officer at the spaceport. "There's one in the central U.S., it'll stay there, it will be blocked by this high pressure ridge. So for Florida, the weather looks really good. Nice mild conditions, warm temperatures. "The day of launch we'll probably be getting up to the mid to upper 70s here at Kennedy Space Center and about mid 70s at the pad. And then as we get into that evening, we'll stay nice and moderate with the southeast flow, the flow off the water keeping temperatures moderate. The only slight concern we have is that a ceiling can sometimes come in ... but really, the chances of that are low and with that, we're going with a 10 percent chance of KSC weather prohibiting launch." With clear skies expected, a rising, nearly-full moon above the launch pad should provide a dramatic backdrop. "One nice little touch on the launch this time is that the moon is going to be rising about one hour before launch," said Winters. "So it'll be in the east and it's a full moon, it's a 99-percent moon-illumination night. So it should be a really nice night for a launch and hopefully, you'll get some good snapshots of that." Discovery's countdown began Sunday evening at 7 p.m. and Launch Director Mike Leinbach said today preparations were proceeding smoothly, with engineers gearing up to pump liquid hydrogen and oxygen aboard the shuttle to power its three electricity producing fuel cells. "Right now, we're not tracking any issues in the firing room that would prevent any major milestones," he said. "A couple of IPRs (interim problem reports) over the weekend, but no big deal. So the team is anxious to go, we're fully trained, ready to execute this mission." Mike Moses, the new chairman of NASA's Mission Management Team at the Kennedy Space Center, said managers had little to discuss at today's launch-minus-two-day meeting. "We had a very short meeting today, which is a record for us with STS-119 from what we've become used to," he said, referring to recent discussions of flow control valve issues. "We talked today about our upcoming operations, we got a weather briefing from Kathy, the launch director, Mike Leinbach, gave us a good status of the team and where they're at. As a management team, we really didn't have that many issues to discuss. We checked with every agency, every center, every project. No one had any issues." The MMT did review the status of an electronic component in a system used to move the shuttle's orbital maneuvering system, or OMS, rockets. A loose circuit card was found in a secondary controller after a recent shuttle flight, but Moses said the system has enough redundancy to handle any such issues should they occur again. "Basically, when they took the lid off the electronics box, there's a piece of foam that helps keep those cards seated in their slots," he said. "And they saw that foam had some compression memory in it and one of the cards was loose. They've looked at some other boxes, pulled those apart, found that same compression in the foam but none of those cards were loose. Looking at the history of it, it looks like this card might have been loose from the very beginning." The shuttle is equipped with two OMS engines for major orbital maneuvers and to provide the braking needed to drop out of orbit. Each engine is equipped with redundant steering control and only one engine is required for deorbit. On top of that, smaller maneuvering jets could be used to drop a shuttle out of orbit if both OMS engines somehow failed. "Redundancy wise, we're in really great shape there," Moses said. "We talked it pretty detailed just to make sure we had a handle on it. Nobody had any issues or concerns and I'm perfectly fine with that and we're ready to fly."
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