Time lapse: Watch the Falcon Heavy placed on pad 39A

Scientists working on a new lightning detection instrument mounted outside the International Space Station said Tuesday they expect little effect on the sensor’s performance from possible contamination from the upper stage of a SpaceX Falcon 9 rocket that launched it into orbit April 2.

Liftoff from pad 40 at Cape Canaveral Space Force Station was set for 4:57 p.m. EST (2157 UTC) Sunday before the mission was scrubbed. SpaceX has not announce a new launch date or time for the mission.

SpaceX plans to begin construction of a new rocket and spacecraft next year that could lead to human landings on Mars as early as 2024, scaling up technologies currently being perfected with the company’s Falcon 9 family of boosters to ensure reliability, reusability and, as a result, realistically low costs, founder Elon Musk said Friday.