Q&A with Keith Gendreau, principal investigator of the first X-ray space communications experiment (members only)

The SpaceX Falcon 9 rocket blasts off Sunday with a dual-satellite payload destined for geosynchronous orbits 22,300 miles above the Earth.

After a six-week delay for undisclosed reasons, SpaceX raised a Falcon 9 vertical on its launch pad Thursday at the Kennedy Space Center in Florida for another try early Friday to send into orbit the company’s next batch of Starlink Internet relay stations and a pair of commercial BlackSky Earth-imaging microsatellites.

A commercial supply ship owned and operated by SpaceX arrived at the International Space Station on Saturday, delivering a pair of NASA experiments to demonstrate satellite refueling techniques and monitor changes in Earth’s forests, along with a special holiday menu of turkey, candied yams, cranberry sauce and shortbread cookies.