J-2X rocket engine testing continues at NASA's Stennis Space Center in Mississippi with the second in a series of tests conducted on Feb. 27.

The 550-second, full-duration test provided critical information on the combustion stability of the engine and on its performance with the nozzle extension. Engineers also continued evaluation of the test stand's clamshell configuration, as well as calibration of the facility's cryogenic flow meters.

J-2X engine testing allows engineers to collect additional data on the next-generation engine that will provide upper-stage power for the new Space Launch System (SLS) under development.

NASA's new SLS rocket is being developed to enable missions farther into space than ever. The SLS Program is managed by NASA's Marshall Space Flight Center in Huntsville, Ala.

Following this series of tests on the A-2 Test Stand, Engine No. 10002 will be transferred to the site's A-1 stand to undergo gimbal (or pivot) tests for the first time. The J-2X engine is the first human-rated liquid oxygen and liquid hydrogen engine developed in the United States in four decades.

It is being designed and built for NASA by Pratt and Whitney Rocketdyne of Canoga Park, Calif.