SpaceX on Tuesday rolled out the rocket booster that the company plans to use to launch the first Starship orbital flight, and Elon Musk shared photos of the enormous vehicle.

Musk’s company has conducted multiple short test flights of Starship prototypes over the past year, but reaching orbit represents the next step in testing the rocket. The company in May revealed its plan for the flight, which would launch from the company’s facility in Texas and aim to splash down off the coast of Hawaii.

Starship prototypes stand at about 160 feet tall, or around the size of a 16-story building, and are built of stainless steel – representing the early version of the rocket that Musk unveiled in 2019. 

The rocket initially launches on a “Super Heavy” booster, which makes up the bottom half of the rocket and stands about 230 feet tall. Together, Starship and Super Heavy will be nearly 400 feet tall when stacked for the launch.

The company rolled out Super Heavy Booster 4 on Tuesday, with Starship prototype 20 expected to launch on top.

SpaceX has been working rapidly to ready Starship and the Super Heavy booster for the orbital flight test, although a local environmental review by the Federal Aviation Administration needs to be completed before the launch happens.

The company is developing Starship to launch cargo and people on missions to the moon and Mars.

While SpaceX’s fleet of Falcon 9 and Falcon Heavy rockets are partially reusable, Musk’s goal is to make Starship fully reusable — envisioning a rocket that is more akin to a commercial airplane, with short turnaround times between flights where the only major cost is fuel.

Overnight Sunday the company installed 29 of the Raptor engines that power the Super Heavy booster, with Musk himself on hand to witness the company’s progress.