Watch the Falcon 9 launch from pad 39A

Forecasters predict mostly cloudy conditions and a chance of light rain for Tuesday morning’s scheduled takeoff of a SpaceX Falcon 9 rocket with a space station-bound supply ship, with a 40 percent chance weather could prevent liftoff during an instantaneous predawn launch opportunity.

The center section of SpaceX’s first Falcon Heavy rocket has been test-fired at the launch company’s test facility in Central Texas, a sign of progress toward the behemoth booster’s long-delayed maiden mission scheduled some time in the final months of 2017.

Two U.S.-German satellites launched more than 15 years ago to measure Earth’s changing gravity field will stop collecting data in November, a few months before a pair of replacement craft will launch to resume gravity measurements, NASA officials said.