Watch conditions at Kennedy Space Center during Tropical Storm Isaias

NASA officials released a nearly five-year, $28 billion plan Monday to return astronauts to the surface of the moon before the end of 2024, but the agency’s administrator said the “aggressive” timeline set by the Trump administration last year hinges on Congress approving $3.2 billion in the next few months to kick-start development of new human-rated lunar landers.

The world’s most powerful operational rocket flashed to life at 2:30 a.m. EDT (0630 GMT) Tuesday and climbed into a moonlit summer sky from pad 39A at NASA’s Kennedy Space Center in Florida, the same site where the Apollo 11 astronauts left Earth for their historic moon landing nearly 50 years ago.

SpaceX test-fired a reused Falcon 9 booster Monday at NASA’s Kennedy Space Center in Florida, checking the rocket’s readiness for a planned liftoff Saturday with an Airbus-built commercial communications satellite.