Photos: Gantry rollback for second launch attempt

After unusual concentrations of hydrogen around the rocket foiled a launch attempt Dec. 19, United Launch Alliance said Friday that the company’s powerful Delta 4-Heavy launcher and a U.S. government spy satellite will remain grounded in California until at least Jan. 6 as engineers troubleshoot a small fuel leak.

Using a new, uprated main engine for the first time on a rocket of its kind, a United Launch Alliance Delta 4-Medium+ vehicle will soar into space Wednesday night carrying a $566 million Air Force communications satellite.

An Atlas 5 rocket lifts off from launch complex 41 at Cape Canaveral carrying the SBIRS GEO-4 missile early warning satellite in this video shot from the Kennedy Space Center Press Site.