CAPE CANAVERAL, Fla. - NASA has renewed hopes of launching the space shuttle Atlantis next week, as the spacecraft made history Tuesday as the first orbiter to return to its launch pad in mid-rollback.
"We're going to give a fighting chance," NASA's launch integration manager LeRoy Cain told reporters in a last-minute briefing here at Kennedy Space Center (KSC).
A target launch date has not been set, but flight controllers plan to pick up the spaceflight's countdown at T minus three days before launch as soon as possible once Tropical Storm Ernesto passes. The flight window for Atlantis' STS-115 mission to the International Space Station (ISS) closes on Sept. 7, a self-imposed deadline that allows a buffer between Atlantis' stay at the orbital laboratory and an arriving Russian Soyuz spacecraft.
NASA launch director Michael Leinbach said pad crews will prepare Atlantis and Pad 39B for Ernesto's arrival, then leave the launch site empty late Wednesday until the storm passes.
"There's no trepidation in my mind at all about the decision," Leinbach said. "This is the right way to go."
Leinbach said Atlantis should return to its Pad 39B launch site at about 8:00 p.m. EDT (0000 Aug. 30 GMT), with shuttle engineers working through the night to reattach conduits and cables before the first wave of weather from Ernesto arrives.
It is Ernesto's imminent arrival that prompted Cain, Leinbach and top shuttle officials to haul Atlantis back to the safe haven of NASA's Vehicle Assembly Building (VAB) here earlier today. The storm's wind speeds were expected to just be barely below the maximum limits allowed for a shuttle-laden launch pad.
But as Atlantis approached the mid-point of its 10-hour trek to the VAB, Ernesto weakened to the point that shuttle officials were convinced the orbiter and its launch stack could weather the storm at Pad 39B.
NASA orbiters cannot withstand wind gusts at peak speeds of 70 knots at the launch pad.
"When it's at its closest to us, it's at 45 knots, gusting to 55 knots," Leinbach said of Ernesto's projected strength when it reaches KSC. "That was the data that allowed us to get comfortable to take the vehicle back to the pad."
NASA's launch window for Atlantis closes on Sept. 7, a self-imposed deadline to allow a buffer between the shuttle flight and Russia's planned launch of Soyuz spacecraft later next month. The shuttle's full window extends through Sept. 13.
Leinbach said that his earlier estimate that eight days would be required to once more ready Atlantis for flight was based on the shuttle retreating the entire 4.2 miles to the VAB.
The spacecraft could now launch some time mid-next week if Ernesto's impact to KSC is minimal, space center workers are able to return to work quickly after the storm and if all of the outstanding tasks to prime Atlantis for flight are completed in time.
While NASA officials told SPACE.com earlier today that a decision had not been made as to whether Atlantis' six-astronaut crew would leave quarantine--where they are isolated from certain family members and others to avoid sickness - Cain said STS-115 team did in fact end their quarantine status.
The astronauts flew back to NASA's Johnson Space Center (JSC) training facility in Houston, Texas, where they will conduct additional training and spend time with their families until a new launch date it set and they reenter quarantine, NASA said.
"It really became a timing issue," Cain said, adding that spacecraft will be protected from Ernesto's rain and winds by Pad 39B's shroud-like Rotating Service Structure. "Probably a day or a day and a half ago, we recognized that this was going to be a close call."
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