A prototype of SpaceX’s rocket that will one day take crews to the Moon, Mars and beyond has passed cryogenic testing, SpaceX founder and CEO Elon Musk said.

Sharing the news on Twitter, Musk said the next step for Starship SN4 will be an engine test later this week.

According to NASAspaceflight.com, the cryogenic proof is one of the first tests necessary to prove the vehicle’s flight-worthiness.

SN4 is the first full-scale Starship prototype to pass this test, which sees the rocket filled with liquid nitrogen to verify that its tanks can withstand flight pressures.

SpaceX’s Starship spacecraft and Super Heavy rocket (collectively referred to as Starship) represent a fully reusable transportation system designed to carry both crew and cargo to Earth orbit, the Moon, Mars and beyond.

According to SpaceX’s website, Starship will be the world’s most powerful launch vehicle ever developed, with the ability to carry in excess of 100 metric tonnes to Earth orbit.

Drawing on an extensive history of launch vehicle and engine development programmes, SpaceX has been rapidly iterating on the design of Starship with orbital-flight targeted for 2020.