NASA logo at the Kennedy Space Center. Florida

NASA has big plans for 2019. First, they plan on sending the most powerful rocket ever built, the Space Launch System, out into the ether. Then, they will send a capsule called Orion on an elaborate 25-day trajectory, according to WiredThe capsule will cruise 245,131 miles away from Earth, loop around the moon, and race back into Earth’s atmosphere at 24,500 miles an hour.

But their plans for 2020 are even bigger. NASA wants to do the same thing as 2019, but will a crew. This mission would send humans farther into space than ever before, according to Wired. 

Wired photographer Vincent Fournier got exclusive access to the testing and preparations for the mission. He spends 20 days at five facilities to capture how they build and test the rocket and its human-carrying capacity.

So how do you build something like the most powerful rocket? Well for one, engineers first build teeny models of the rocket and stick them in wind tunnels first.

The fuel tank dome is assembled with a technique called friction stir welding. Wired explains that this is when cylinders of metal rotate between aluminum slabs, which heat the slabs until they have a butter-like consistency. The metal sections are then melded together, so there are no cracks or contaminants and sanded by hand. To double-check for any issues, technicians use ultrasounds and X-rays.

Meanwhile, moving the 130-foot-tall hydrogen fuel tank from a horizontal to vertical position takes three days, two GPS-enabled cranes, and a laser alignment system to position the hardware, writes Wired. 

To be approved for flight, a test model of the RS-25 engine is put into a test stand at NASA Stennis and blasted for 500 seconds in “a sequence identical to launch–just with no rocket attached,” writes Wired. The engineers watch from a quarter-mile away, for safety.