LAUNCH DAY: Endeavour to try again Today

Following five launch postponements due to leaks and thunderstorms, the space shuttle Endeavour will try again today to depart earth on a 16 day construction job at the international space station.

Liftoff from here at the Kennedy Space Center's launch pad 39-A is set for 6:03:10 pm EDT. The launch window lasts five minutes.

Thunderstorms within twenty miles of the shuttle's launch pad and her emergency runway forced NASA to cancel launch attempts on Sunday and Monday evenings with only nine minutes left in the count. If thunderstorms along the Space Coast force a launch postponement tonight, NASA will try one last time on Thursday before standing down until July 28 due to an unmanned Russian cargo ship's docking with the station on July 30.

Once in earth orbit, Endeavour (above, this morning) and her crew of seven will spend two days to catch up with and dock to the international space station. An on time launch today would see Endeavour dock with the station on Friday afternoon to begin two weeks of docked operations.

Orbiting 220 miles high, the two vehicles will come together to compete the building of the Japanese Kibo module with the final segment - a huge tray platform which will host a variety of experiments exposed to the vacuum of space. "Kibo" means hope in Japan.

The crew will also perform five spacewalks over five days beginning on Saturday morning to make repairs, change out batteries and help install the Japanese Experiment Platform.

Led by veteran commander Mark "Roman" Polansky, Endeavour's crew includes pilot Doug Hurley and mission specialists David A. Wolf, Christopher Cassidy, Tom Marshburn, Timothy Kopra and Julie Payette (Canadian Space Agency).

The flight crew awoke just after 7:00 am this morning to begin their launch day.

Endeavour Launch Milestones Today (EDT):

• 8:38a - T-:06 hours and counting
• 8:38a - External tank fueling begins
• 12:00p - ET fueling complete
• 1:43p - Crew begins donning flight suits
• 2:08p - T-:03 hours and counting
  
• 2:13p - Crew departs for Launch Pad 39A
• 2:44p - Crew begins boarding Endeavour
• 4:00p - Endeavour hatch closeure
  
• 5:09p - T-:9 minutes and Holding (40 mins)
• 5:58p - Pilot Hurley performs APU start
• 6:03:10p - Solid Rocket Boosters ignite - Launch commit!
• 6:05:18p - SRB seperation
• 6:11:40p - MECO Endeavour's engines shutdown
• 6:45p - OMS-02 burn to circularize their orbit
  

If Endeavour does launch this evening, it will come just 15 hours prior to the 40th anniversary minute mark of humanity's first lunar landing mission, Apollo 11.

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