NASA’s “red-letter day”



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Like a high-priced athlete determined to rise from the developmental league, NASA’s first Space Launch System rocket is starting to look formidable in the Vehicle Assembly Building at Kennedy Space Center in Florida, the same building where the space shuttles and Apollo rockets were once readied for launch.

Related: Q&A with NASA Administrator Bill Nelson.

In June, after lowering the SLS core stage between its two solid rocket boosters and bolting them together, technicians from NASA and its contractor Jacobs turned to the finer points of preparing the expendable rocket for the design’s uncrewed debut no earlier than Nov. 22 for the Artemis lunar program.

The conical Launch Vehicle Stage Adapter was stacked on top of the core stage to be followed by the liquid-hydrogen-fueled Interim Cryogenic Propulsion Stage, whose single engine must propel Orion and its solar panel-equipped service module on a flyby of the moon to within 100 kilometers of the surface and then, with the aid of lunar gravity, out to a distance of 70,000 kilometers beyond the moon. Next will come the Orion Stage Adapter, an aluminum ring fitted with a composite diaphragm to prevent hydrogen gas from the upper stage from building up beneath the European-supplied service module and Orion crew module. Those will be stacked last and topped with the Launch Abort System motors, bringing the height to 98 meters. The 26-day Artemis 1 mission will end with the Orion crew capsule splashing down in the Pacific Ocean, as though it were bringing astronauts home from the moon.

A successful test, says NASA Administrator Bill Nelson, would be a “red-letter day” for the agency and the $28 billion, four-years-late SLS program.

You should know

• Artemis 1 was formerly called Exploration Mission-1
• Launch date: Nov. 22 is the “earliest possible date” and is for “planning purposes,” says NASA.

Who makes what

Core stage: Boeing (contains four RS-25 engines, flown previously on space shuttle missions, built by Aerojet Rocketdyne).
Solid rocket boosters: Northrop Grumman
Launch vehicle stage adapter: Teledyne Brown Engineering
Interim cryogenic propulsion stage: Boeing and United Launch Alliance (powered by a single Aerojet Rocketdyne RL-10B2 engine, like those on Delta IV second stages).
Orion stage adapter: NASA’s Marshall Space Flight Center
Service module: European Space Agency and Airbus
Orion capsule: Lockheed Martin

NASA’s “red-letter day”