A powerful Delta IV rocket is being prepared for liftoff tonight from Cape Canaveral with a military communications satellite.
The launch is scheduled for 8:29 p.m., the opening of a 49-minute window.
The forecast calls for an 80 percent chance of favorable weather, with a chance of clouds from a coastal shower.
At Cape Canaveral Air Force Station's Launch Complex 37, a mobile service tower has backed away from the 217-foot rocket.
Super-cold liquid hydrogen and liquid oxygen are slated to begin flowing into the rocket's first- and second stage tanks this afternoon.
Atop the rocket is the U.S. Air Force's sixth in a system of high-capacity communications satellites called Wideband Global SATCOM, or WGS, built by The Boeing Co.
The launch is the 23rd by a Delta IV rocket but only the fourth in this vehicle configuration, called Medium+, with four strap-on solid rocket motors and a five-meter payload fairing.
Written by James Dean, FLORIDA TODAY