T-:43 hours and counting...
Moments ago, at 9:00:00 am EDT, Launch Control's Firing Room #4 came to life as the countdown for this Saturday's space shuttle launch began on time.
Even though there is 2 days, 22 hours and 17 minutes until Saturday's 7:17 am EDT launch, the countdown has several built-in holds ranging in times of 10 minutes to several hours long. These holds give the launch team added time in case an issue arises during the count.
Currently, there is a 90% weather "Go" from the spaceflight meteorology group here at Cape Canaveral's Patrick, AFB.