Some assembly required

Some assembly required
Some assembly required Four RS-25 flight engines, like the one shown at top, will be turned upside down and mounted to the rocket's engine section (middle) using the white pins (bottom). The engine is currently stored at Aerojet Rocketdyne's facility at Stennis Space Center, Mississippi, but will be mounted to the SLS hardware at the Michoud Assembly Facility in New Orleans. Jason Davis / The Planetary Society

"We're changing the world. Are you in?"
- CEO Bill Nye

Sign up for email updates