SpaceX's Falcon Heavy undergoes test firing ahead of upcoming launch.

SpaceX test-fired 27 main engines on a Falcon Heavy rocket in Florida, ahead of installing three commercial communications satellites for a mission to geostationary orbit next week. The primary payload is ViaSat 3 Americas, a bus-sized spacecraft built by Boeing to beam internet signals across the Americas and adjacent maritime regions. Smaller rideshare communications satellites for Astranis and Gravity Space, both commercial startups, will also hitch a ride to geostationary orbit on the Falcon Heavy rocket.