Live coverage: Atlas 5 countdown and launch journal

Launch of an Atlas 5 rocket from Cape Canaveral with a U.S. Air Force infrared surveillance satellite was scrubbed Thursday evening after engineers encountered a balky valve associated with the first stage’s liquid oxygen system.

Navigation satellites, communications spacecraft, classified missions, NASA science projects and the Orbital Sciences Cygnus cargo ship destined for the International Space Station are on the United Launch Alliance manifest for the new year.

A United Launch Alliance Delta 4 rocket will deliver the U.S. Air Force’s tenth Wideband Global SATCOM communications satellite to a supersynchronous transfer orbit around 37 minutes after lifting off from Cape Canaveral.