Falcon Heavy hot fire as seen from Kennedy Space Center Press Site

A pair of European-built, NASA-backed research satellites set for launch Tuesday from California will extend 15 years of global gravity field measurements collected by the GRACE mission before it ended last year, supplying scientists with data to help track the melting of Earth’s ice sheets and chart the impacts of floods and droughts.

SpaceX test-fired the Crew Dragon spacecraft’s eight SuperDraco abort engines Wednesday at Cape Canaveral, paving the way for a high-altitude rocket escape test and demonstrating engineers have apparently fixed the problem that triggered an explosion during a similar ground firing in April.

SpaceX launched one Starlink mission from Florida but plans for a back-to-back overnight mission from the west coast were dashed after the Falcon 9 flying from Vandenberg Space Force Base California was delayed to Friday.