NASA has showcased a rocket engine verification test to more than 1,500 visitors during an open house event at Stennis Space Center on Thursday.

The agency said Friday it tested the RS-25 engine E2063, which is one of four RS-25 engines that will power the crewed and uncrewed flights of the Space Launch System rocket.

NASA engineers will use data from the verification test to certify the engine for use on an actual SLS mission.

During the test, NASA fired and throttled the anchored engine in the same way and length of time that will be performed on an actual launch.

Engine E2063 will be used on the second integrated flight test of SLS and the Orion crew vehicle, dubbed Exploration Mission-2, that will carry astronauts to space.

The Stennis Founders Day Open House event marked the 56th founding anniversary of the center and showcased NASA’s deep space plans as well as space-related exhibits.

Stennis has been assigned to test the rocket engines and stages for the SLS Program.