Q&A with Mike Laidley, vice president of Orbital ATK’s Next Generation Launch program (members only)

Rainy weather expected across Central Florida this weekend has a 50-50 chance of preventing the launch of a SpaceX Falcon 9 rocket Saturday on a resupply mission to the International Space Station, U.S. Air Force forecasters said Wednesday.

The United Launch Alliance Delta 4 Medium+ (4,2) rocket lifted off at 12:52 a.m. EDT (0452 GMT) from Cape Canaveral for the Geosynchronous Space Situational Awareness Program.

A SpaceX-owned commercial cargo craft splashed down in the Pacific Ocean west of Baja California late Sunday, closing out a 39-day mission that delivered 2.8 tons of supplies, experiments and holiday treats to the International Space Station, and returned home with research specimens and no-longer-needed hardware.