Video: DSCOVR prepared for launch

A rocket recovery team positioned off Florida’s East Coast is standing by for liftoff Sunday of a Falcon 9 launcher with a space weather satellite, but the demanding trajectory of the flight adds more unknowns to the company’s dicey endeavor to land the booster on a ship at sea.

The world’s most distant weather outpost is set for liftoff from Cape Canaveral on Sunday aboard a SpaceX Falcon 9 rocket, launching to a point a million miles from Earth to warn forecasters of solar storms that could disrupt global air traffic, satellite navigation and power grids.

A problem with a U.S. Air Force tracking radar kept a Falcon 9 rocket crowned with a NOAA space weather observatory grounded Sunday, forcing a long-delayed mission to stay on Earth an extra day.