Rainbow view of NASA’s RS-25 Engine Test

A test fire on the A-1 Test Stand at Stennis Space Center near Bay St. Louis, Mississippi, on Feb. 22, 2017.

NASA conducted eight RS-25 engine tests in 2017 for the Space Launch System rocket.

Flight preparations are complete for the four liquid fuel engines that will help power SLS on its first mission, and engineers began testing engines for the second mission that will carry crew.

Four RS-25 engines will help power the SLS at launch, providing a combined 2 million pounds of thrust and firing in conjunction with a pair of solid rocket boosters.

The 10 motor segments have been cast for the two solid rocket boosters, and they are on track to be ready for the first integrated test flight. With the boosters, total thrust at liftoff will exceed 8 million pounds.