Gallery: Antares rocket explodes

An unpiloted space plane developed by Sierra Nevada Corp. will join cargo carriers built by SpaceX and Orbital ATK to resupply the International Space Station beginning in 2019, NASA announced Thursday.

These narrated videos show the pre-launch preparations that readied the United Launch Alliance Atlas 5 rocket and the Orbital ATK Cygnus commercial cargo-delivery spacecraft for flight and rolling to Complex 41 for liftoff to the International Space Station.

Racing against the clock to meet the Trump administration’s 2024 deadline to land astronauts on the moon, NASA plans to select Northrop Grumman to build a pressurized habitation module derived from the company’s Cygnus cargo craft for living quarters for crews transiting to and from the lunar surface.