Live coverage: Atlas 5 countdown and launch journal

The United Launch Alliance Delta 4 rocket sits peacefully inside its mobile service gantry on Tuesday afternoon, one day before its scheduled launch of the GPS 2F-9 navigation satellite.

NASA is gearing up for an intense few weeks of work aboard the International Space Station, staging three spacewalks, moving a docking port from one module to another to support commercial crew ferry ships and capturing an Orbital ATK Cygnus cargo ship carrying nearly 4 tons of equipment and supplies.

Ground crews at Vandenberg Air Force Base on California’s Central Coast hoisted NASA’s InSight Mars lander atop a United Launch Alliance Atlas 5 rocket Monday, kicking off nearly two weeks of integrated tests and checkouts before the probe’s interplanetary launch window opens May 5.