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

Northrop Grumman’s Pegasus XL rocket will take about 11 minutes to place NASA’s Ionospheric Connection Explorer, or ICON, satellite into a roughly 357-mile-high (575-kilometer) orbit after an airborne launch off Florida’s east coast.

SpaceX test-fired nine Merlin engines Saturday before the company’s next launch from Cape Canaveral, clearing a key readiness test before liftoff as soon as Sunday night with 60 more Starlink internet satellites.

Technicians planned to attach two Boeing-built communications satellites to a SpaceX Falcon 9 rocket Monday, a day after launch controllers fueled the rocket and fired its nine Merlin first stage engines in a key preflight test.