Endeavour Poised for Wednesday Launch

The space shuttle Endeavour is poised for a one and only try to launch during the next few weeks tomorrow morning on a resupply and equipment delivery mission to the international space station.

Liftoff of Endeavour with a crew of seven is targeted for 5:40:52 am EDT, Wednesday morning from here at the Kennedy Space Center.

A gaseous hydrogen vent seal has been repaired at the connection point of a line running from launch pad 39-A to Endeavour's 15 story external fuel tank, allowing space shuttle program managers to give the STS-127 mission one launch try tonight before stepping down until mid-July.

A lunar exploration launch aboard a United Launch Alliance Atlas V, and what NASA calls a "beta cutout" due to the space station's attitude would keep Endeavour grounded until July 11.

At 1:15 pm today, launch control's firing room 4 will resume the countdown at the T-:11 hour mark.

At 8:15 pm tonight, launch control will begin to slowly fill the external fuel tank of Endeavour with nearly 500,000 gallons of super cold liquid oxygen & liquid hydrogen. It was about two hours into fueling during Saturday's first launch attempt that the launch team saw the LH2 leak in a gaseous state as it bleeds off. Fueling should be completed three hours later.

Meanwhile, a few miles away here at KSC, the crew will begin to suit up at about 1AM. The crew is set to begin boarding the space shuttle at pad 39-A at 2:20 am.

Led by commander Mark Polansky, this flight will deliver a huge external experiment tray for attachment to the station's Japanese Kibo module; perform five spacewalks in support of station construction; install new batteries and bring up a new crew member to live aboard the ISS for two months.

Watch the entire mission of Endeavour LIVE beginning tonight via SpaceLaunchNews.com. Also, follow us via Twitter @spacelaunchnews.