Live coverage: Ariane 5 rocket deploys satellites for Australia, India

Blaming a slew of technical snags and “avoidable errors,” NASA officials said Tuesday that the launch of the James Webb Space Telescope, already years behind schedule, will be delayed to 2020, potentially pushing the mission’s development cost above an $8 billion cap mandated by Congress.

SpaceX has postponed the launch of its next Falcon 9 rocket indefinitely. The rocket was originally scheduled take off Wednesday from pad 39A at NASA’s Kennedy Space Center in Florida with a top secret U.S. government payload named Zuma. A few minutes after launch, the Falcon 9’s first stage will return for a landing at nearby Cape Canaveral Air Force Station.

Europe’s first mission to Mercury, a quartet of Galileo navigation spacecraft, the world’s first global winds observatory, and a new European weather satellite have arrived at an equatorial launch base in French Guiana in preparation for launches in the coming months.