Live coverage: Atlas 5 countdown and launch journal

The United Launch Alliance Atlas 5 rocket stands poised for flight with the Air Force’s X-37B spaceplane and a batch of CubeSats including the LightSail. The rocket was rolled to Complex 41 on Tuesday in preparation for launch on Wednesday.

Two days after blasting off from Virginia’s Eastern Shore, Orbital ATK’s Cygnus supply ship reached its destination Tuesday. The automated spacecraft packed with 3.7 tons of supplies and experiments was captured by the International Space Station’s robotic arm at 5:04 a.m. EST (1004 GMT).

Forecasters predict a 90% chance of good weather for liftoff of a United Launch Alliance Atlas 5 rocket from Cape Canaveral just after sunset Tuesday with a classified payload for the National Reconnaissance Office, the U.S. government’s spy satellite agency.