The space shuttle Atlantis rolled out toward its Florida launch pad early Wednesday to prepare for a November liftoff, even though NASA is still unsure of exactly when the spacecraft will fly.
NASA is targeting a planned Nov. 12 launch from Pad 39A at the Kennedy Space Center in Florida for Atlantis and a crew of seven to deliver a vital load of supplies and spare parts to the International Space Station. It will be the agency's fifth shuttle launch of the year — the most since 2002.
But NASA currently does not officially have a slot for Nov. 12 on the Eastern Range over the Atlantic Ocean, which the space agency shares with the nearby Cape Canaveral Air Force Station for shuttle flights and unmanned rocket launches, an agency spokesperson said. The agency plans to make a formal decision on when to launch Atlantis during an Oct. 29 readiness review.
NASA has invited up to 100 of its followers on Twitter to watch the launch in person as part of the agency's tweetup campaign. Registration for the event opens on Friday via NASA's tweetup Web site.
Launch date limbo
There are two unmanned rocket launches scheduled in November that NASA must work around in order to try to launch Atlantis next month. The agency is also watching the Leonids meteor shower, which is expected to peak Nov. 17, to be sure Atlantis doesn't launch at the shower's height.
NASA is hopeful that it can get at least three launch attempts for Atlantis in November, before standing down around Nov. 19 or 20 due to unfavorable sun angles at the space station, which can cause heating and power concerns, agency officials said.
"We still have some negotiating to do," NASA spokesperson Allard Beutel told SPACE.com from the spaceport. "Whatever day it ends up being, we're getting ourselves in a position to be ready to launch."
Wednesday's launch pad rollout is part of that plan.
NASA began hauling Atlantis toward Launch Pad 39A at 6:38 a.m. EDT using its massive crawler carrier vehicle originally built for the Apollo flights in the late 1960s and 1970s. The 12 million-pound (5.4 million-kg) combo of the Atlantis and its carrier can move at a top speed of about 1 mph (1.6 kph).
The trip began a bit late due to last minute glitches and took nearly seven hours to traverse the 3.4-mile (5.4-km) river rock-lined crawlerway to Pad 39A.
Preparing for launch
On Monday, Atlantis' six astronauts — commanded by veteran spaceflyer Charlie Hobaugh — will arrive at the Kennedy Space Center to begin several days of final training that will end with a launch dress rehearsal and emergency escape drill, Beutel said. They spent today training in a shuttle simulator at NASA's Johnson Space Center in Houston.
Hobaugh and his crew are slated to launch toward the space station at 4:04 p.m. EST (2104 GMT) on Nov. 12 on an 11-day mission. Three spacewalks are planned to deliver a set of large spare parts for the outpost. The shuttle will also return NASA astronaut Nicole Stott — who arrived at the station Aug. 30 to join its six-person crew — back to Earth.
Atlantis' launch pad trek was initially scheduled for Tuesday. But delays caused by a crane, wiring and solid rocket booster cable glitches kept the shuttle from rolling out until today.
NASA is also preparing for the planned Oct. 27 launch of its first Ares I rocket demonstrator, the suborbital Ares I-X booster, at the Kennedy Space Center. That rocket is slated to roll out to the nearby Launch Pad 39B on Oct. 19.
Still, engineers have about three days of padding in their work schedule for a potential Nov. 12 launch, Beutel said. If Atlantis does not launch in November, the next opportunity could arise in December, he added.