Live coverage: Atlas 5 countdown and launch journal

The United Launch Alliance Atlas 5 rocket was transfered from its assembly building to the pad at Cape Canaveral’s Complex 41 today for Tuesday’s launch of a commercially-operated cargo ship to resupply the International Space Station.

United Launch Alliance teams began stacking an Atlas 5 rocket inside a vertical hangar at Cape Canaveral Monday in preparation for an early February launch with the Solar Orbiter spacecraft, a joint U.S.-European probe that will take the first pictures of the sun’s poles.

Arianespace’s third Ariane 5 launch of the year was set liftoff Friday from Kourou, French Guiana, but an issue with a sensor on the rocket’s first stage liquid hydrogen tank caused officials to scrub the launch attempt. The Ariane 5 is poised to carry three U.S.-built commercial satellites into orbit, while testing a few rocket upgrades, including a modified fairing needed for the launch of the James Webb Space Telescope next year.