Stennis employees at the E-1 Test Stand position an Aerojet AJ26 rocket engine in preparation for a series of early tests. Stennis has partnered with Orbital Sciences Corporation to test the rocket engine for the company's commercial cargo flights to the International Space Station.

John C. Stennis Space Center engineers conduct a 55-second test fire of Aerojet's liquid-fuel AJ26 rocket engine that will power the first stage of Orbital Sciences Corporation's Taurus II space launch vehicle. The Dec. 17, 2010 test was conducted on the E-1 Test Stand at Stennis in support of NASA's Commercial Transportation Services partnerships to enable commercial cargo flights to the International Space Station. Orbital is under contract with NASA to provide eight cargo missions to the space station through 2015.

John C. Stennis Space Center engineers conduct a 55-second test fire of Aerojet's liquid-fuel AJ26 rocket engine that will power the first stage of Orbital Sciences Corporation's Taurus II space launch vehicle. The Dec. 17, 2010 test was conducted on the E-1 Test Stand at Stennis in support of NASA's Commercial Transportation Services partnerships to enable commercial cargo flights to the International Space Station. Orbital is under contract with NASA to provide eight cargo missions to the space station through 2015.

NASA Administrator Charles Bolden (l) and John C. Stennis Space Center Director Patrick Scheuermann watch the successful test of the first Aerojet AJ26 flight engine Feb. 7, 2011. The test was conducted on the E-1 Test Stand at Stennis. The engine now will be sent to Wallops Flight Facility in Virginia, where it will be used to power the first stage of Orbital Sciences Corporation's Taurus II space vehicle. The Feb. 7 test supports NASA's commitment to partner with companies to provide commercial cargo flights to the International Space Station. NASA has partnered with Orbital to carry out the first of eight cargo missions to the space station in early 2012.

An Aerojet AJ26 rocket engine is hoisted for installation at Stennis Space Center's E-1 Test Stand on July 19. Stennis operators have been preparing the E-1 stand for testing AJ26 engines since April 2009. Modifications included construction of a 27-foot-deep flame deflection trench.

An Aerojet AJ26 rocket engine is hoisted for installation at Stennis Space Center's E-1 Test Stand on July 19. Stennis operators have been preparing the E-1 stand for testing AJ26 engines since April 2009. Modifications included construction of a 27-foot-deep flame deflection trench.

NASA engineers tested an Aerojet AJ26 rocket engine on the E-1 Test Stand at Stennis Space Center on June 25, 2012, against the backdrop of the B-1/B-2 Test Stand. The engine will be used by Orbital Sciences Corporation to power commercial cargo flights to the International Space Station.

Fire and steam signal a successful test firing of Orbital Sciences Corporation's Aerojet AJ26 rocket engine at John C. Stennis Space Center. AJ26 engines will be used to power Orbital's Taurus II space vehicle on commercial cargo flights to the International Space Station. On Nov. 10, operators at Stennis' E-1 Test Stand conducted a 10-second test fire of the engine, the first of a series of three verification tests. Orbital has partnered with NASA to provide eight missions to the ISS by 2015.

NASA Deputy Administrator Lori Garver and U.S. Rep. Steven Palazzo, R-Miss., view a May 3, 2012, test of the Aerojet AJ26 rocket engine on the E-1 Test Stand at Stennis Space Center. The AJ26 engine is being tested for Orbital Sciences Corporation to power commercial cargo flights to the International Space Station.

NASA Deputy Administrator Lori Garver and U.S. Rep. Steven Palazzo, R-Miss., view a May 3, 2012, test of the Aerojet AJ26 rocket engine on the E-1 Test Stand at Stennis Space Center. The AJ26 engine is being tested for Orbital Sciences Corporation to power commercial cargo flights to the International Space Station.

A team of engineers from NASA's John C. Stennis Space Center, Orbital Sciences Corporation and Aerojet conduct a successful test of an Aerojet AJ26 rocket engine on March 19. Stennis is testing AJ26 engines for Orbital Sciences to power commercial cargo missions to the International Space Station. Orbital has partnered with NASA through the Commercial Orbital Transportation Services initiative to carry out eight cargo missions to the space station by 2015, using Taurus II rockets.

NASA conducted a Sept. 28 test of an Aerojet AJ26 flight engine that will power the first stage of Orbital Sciences Corporation's Taurus II space launch vehicle, continuing progress in a key commercial space transport partnership. Orbital is scheduled to begin commercial cargo flights to the International Space Station in 2012.

Stennis Space Center test-fired Aerojet AJ26 flight engine No. 8 on Dec. 15, continuing a commercial partnership with Orbital Services Corporation. Orbital has partnered with NASA to provide commercial cargo flights to the International Space Station. The AJ26 engines tested at Stennis will power the company's Taurus II space launch vehicle on the flights.

A team of engineers at Stennis Space Center conducted a test firing of an Aerojet AJ26 flight engine Nov. 17, providing continued support to Orbital Sciences Corporation as it prepares to launch commercial cargo missions to the International Space Station. AJ26 engines will power Orbital's Taurus II rocket on the missions.

NASA John C. Stennis Space Center employee Dustan Ladner (left) assists tanker driver David Velasco in transferring RP-1 fuel to a 20,000-gallon underground tank at the E-1 Test Stand during a March 30 delivery. The rocket propellant will be used for testing Aerojet AJ26 rocket engines beginning this summer. Stennis is testing the engines for Orbital Sciences Corporation, which has partnered with NASA to provide eight supply missions to the International Space Station through 2015. The partnership is part of NASA's Commercial Orbital Transportation Services initiative to work closer with companies to provide commercial space transport once the space shuttle is retired later this year.