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

SpaceX’s Falcon 9 rocket is set for liftoff from Cape Canaveral on Tuesday, heading due east over the Atlantic Ocean to deliver the GovSat 1 communications satellite into orbit around 32 minutes later.

Final preparations began this weekend at NASA’s Stennis Space Center in Mississippi to load super-cold liquid hydrogen and liquid oxygen into the massive core stage of the Space Launch System heavy-lift rocket for the first time as soon as Monday.

U.S. Air Force officials signed off Monday on a plan for SpaceX and United Launch Alliance, rivals in the launch services market, to fire off Falcon 9 and Atlas 5 rockets from neighboring launch pads at Cape Canaveral on Tuesday evening and Thursday morning.