Photos: Atlas 5 rocket aims for International Space Station

SpaceX’s first Falcon Heavy rocket is expected to roll out to pad 39A at NASA’s Kennedy Space Center for the first time next month for a hold-down firing of its 27 Merlin main engines, but the mega-rocket’s inaugural test launch will slip into January, officials confirmed Tuesday.

The Atlas 5 countdown leading up to Friday’s early morning liftoff from Cape Canaveral with Boeing’s Starliner crew capsule will be several hours longer than usual.

One of five CubeSats deployed from the International Space Station last month is testing a steerable drag brake that could find use in future smallsats to return experiment samples to the ground from low Earth orbit, or on low-cost micro-probes to explore other planets.