technical high confidence

NASA Begins Installing RS-25 Engines Into Artemis III SLS Core Stage

| Artemis II

Technicians at NASA Kennedy Space Center's Vehicle Assembly Building began installing the four RS-25 engines into the Artemis III SLS core stage on August 24, 2026, marking the next phase of core-stage integration after the engine section was mated to the upper four-fifths of the stage earlier in the summer. Each engine weighs roughly 7,700 pounds, produces nearly 500,000 pounds of thrust, and will fire continuously for more than eight minutes during ascent. The four engines assigned to Artemis III — E2048, E2052, E2054, and E2057 — are flight-proven Space Shuttle veterans; E2048 previously flew on Discovery's STS-95 in 1998 (the mission that returned Sen. John Glenn to orbit) and on Atlantis's STS-129. In parallel, solid rocket booster segment stacking in High Bay 3 passed the halfway mark after beginning in early July, and the four Artemis III crew members (Bresnik, Douglas, Rubio, Parmitano) continued an intensive training flow covering water survival, spacesuit operations in the Neutral Buoyancy Lab, and integrated mission-control simulations.

Technicians prepare to transfer RS-25 engines for integration with the Artemis III core stage, Aug. 25, 2026, inside the Vehicle Assembly Building at Kennedy Space Center
Technicians prepare to transfer RS-25 engines for integration with the Artemis III core stage, Aug. 25, 2026, inside the Vehicle Assembly Building at Kennedy Space Center — NASA