IN 2019, NASA will send a capsule called Orion on an elaborate 25-day trajectory. First, the Space Launch System, the most powerful rocket ever built, will blast it into the ether. Then the capsule will coast 245,131 miles away from Earth, loop-de-loop around the moon, and scream back into Earth’s atmosphere at 24,500 miles an hour. In the early 2020s, NASA plans to do the same thing again but with a crew—that mission will send humans farther into space than ever before. It’s one small step in a decades-spanning effort to send astronauts to explore asteroids, Mars, and beyond.
NASA gave photographer Vincent Fournier exclusive access to the testing and preparations for the mission, and our photographer spent 20 days at five facilities to capture how engineers build and test (and test, and test) the unprecedentedly large rocket and its human-carrying capsule. Engineers model everything from the orientation of rocket parts during transit to the way engine vibrations affect other components of the launch system. They’re building teeny models of the rocket and sticking them in wind tunnels; enlarging the agency’s trusty barge Pegasus to ferry massive hunks of metal from NASA’s Michoud facility in Louisiana to Stennis Space Center in Mississippi and finally to Kennedy Space Center in Florida; and testing the fuel tanks by using hydraulic cylinders that apply millions of pounds of crushing forces to mimic launch and flight. “You know ‘measure twice, cut once’?” says Andy Schorr, a manager of the rocket’s payload integration at NASA. “We take that to a whole new level.” Here’s what goes on before the rocket goes up.
Fuel tank dome, Michoud Assembly Facility, Louisiana (Above):
NASA is assembling most of the core stage of the rocket using a technique called friction stir welding: Cylinders of metal rotate between aluminum slabs, heating them to a butter like consistency. The metal sections then meld together without any cracks or contaminants. After sanding the joins by hand, technicians scan them for defects using ultrasound and X-rays.
Hydrogen fuel tank, Michoud Assembly Facility:
The 130-foot-tall hydrogen fuel tank for the rocket is so unwieldy and delicate that moving it from a horizontal to a vertical position (or vice versa) requires three days, two GPS-enabled cranes, and a laser alignment system to position the hardware. The man in the chair? He’s there to push the emergency Stop button. Just in case.
Launch vehicle stage adapter, Marshall Space Flight Center, Alabama:
A pair of NASA technicians will spend three months hand-spraying insulation onto this 28-foot-tall adapter, which connects the core stage to the capsule stage. They’ve practiced for hundreds of hours on more than 50 test sprays so they can achieve a perfectly even layer every time. The polyurethane foam is whitish when it’s sprayed but turns iconic rocket orange when exposed to UV light at liftoff.
Dome weld tool, Michoud Assembly Facility, Louisiana:
To ensure a perfectly welded fuel tank dome, a crew of six takes a day or two just to clamp all the hardware in place on this Circumferential Dome Weld Tool. The blue bars align the two sections of the dome, and after the weld is complete, the crew uses an elaborate ceiling-mounted pulley system to lift the dome off the tool.
RS-25 engines, Stennis Space Center, Mississippi:
Four of these engines will make the SLS go; they can withstand temperatures from –423° F (the fuel stored in the tanks) to 6,000° F (the fuel at ignition). A contractor has updated them to produce a combined 2 million pounds of thrust at liftoff, and engineers have recently finished modeling the acoustics around the bell-shaped nozzles to ensure they can tolerate those bone-rattling vibration patterns.
Intertank, Michoud Assembly Facility, Louisiana:
The rocket’s two unprecedentedly powerful boosters attach to the intertank, the core stage’s sturdiest part. It’s too thick to weld together, so instead the intertank is constructed from 7,500 bolts and eight panels, whose holes have been oh-so-carefully aligned with an assembly jig (the scaffolding) and inspected with X-rays. After it’s constructed, NASA stress-tests it with more than 100 hydraulic actuators, some as heavy as cars.
Systems Integration Test Facility, Marshall Space Flight Center:
Five miles of riotous wiring connects 46 avionics boxes, which control everything from navigation to the engines. Each box is tested in thermal chambers and on very large shake tables to see how they hold up to extreme heat, cold, and vibration. Then they’re all hooked together on these racks—curved to mimic the rocket—to run full launch simulations.
Systems Integration Test Facility, Marshall Space Flight Center, Alabama:
The outer surface of these avionics racks hosts several computers that simulate the rocket’s environment on its entire trajectory, from liftoff to booster separation. Accompanied by realistic animations, the simulation feeds in flaming hot and space-cold temperatures to the sensors, delivers faux coordinates to the flight computer, and sends other flight “data” via 5 miles of cabling.
Unitary Plan Wind Tunnel, Langley Research Center, Virginia:
To make sure the rocket can withstand the supersonic winds of liftoff and flight, NASA engineers test every portion of its trajectory in wind tunnels. This three-foot steel scale model is coated with pastel pink paint that glows intensely neon under a blacklight depending on how much oxygen hits it. (Oxygen is a proxy for pressure in these tests.) Engineers can then determine exactly what forces the wind is exerting on the rocket and ensure that when the boosters separate from the rocket, they won’t, say, whip around and hit the thing.
Orion test capsule, Johnson Space Center, Texas:
The Navy uses a test capsule to practice retrieving astronauts from the ocean after Orion splashes down. Another is undergoing structural tests to see how it will fare if lightning strikes near the launch pad. NASA uses the capsule below to develop procedures for emergency situations. In one, astronauts would stuff dense stowage bags around them to block intense radiation from sudden solar flares.