Photos: Atlas 5 rocket aims for International Space Station

SpaceX’s launch team loaded liquid propellants into the company’s first upgraded Falcon 9 Block 5 rocket Friday at the Kennedy Space Center in Florida, and the countdown rehearsal culminated in a brief ignition of the launcher’s nine Merlin main engines on the launch pad.

The latest launch date was announced late Wednesday evening, following a Tuesday night notice that May 25 was off the table. Liftoff of the Atlas 5 rocket on June 1 is set for 12:25 p.m. EDT (1625 UTC).

Rocket Lab announced this week it has added two more nanosatellites to the first operational launch of the company’s Electron rocket, which is now scheduled to take off from New Zealand no earlier than Nov. 10, U.S. time, after a multi-month delay to resolve a technical problem.