Live coverage: Atlas 5 countdown and launch journal

United Launch Alliance has completed stacking of the major elements of the Atlas 5 rocket assigned to power NASA’s Perseverance rover toward Mars, but the mission’s launch date has been pushed back three days to July 20 after teams repaired an issue with a crane in the Atlas 5’s assembly building.

An unpiloted test flight of Boeing’s Starliner crew capsule to the International Space Station will be delayed from its previous target launch date of April 2 until at least May, after the arrivals of Russian Soyuz and SpaceX Crew Dragon ships bringing fresh crew members to the orbiting complex, NASA officials said Monday.

Technicians are putting the final touches on a United Launch Alliance Delta 4 rocket set for liftoff Thursday from Vandenberg Air Force Base, a military base on California’s Central Coast, with a top secret spy satellite for the National Reconnaissance Office.