SpaceX completes engine tests for Lunar Starship

SpaceX performs a 281-second throttle test of its Raptor engine to demonstrate the ability of Starship to perform a powered decent to the lunar surface. Credit: SpaceX
In a NASA update, the agency detailed two engine tests completed by SpaceX for the Starship human landing system, which is expected to be used for the Artemis 3 and 4 Moon landings later this decade.
The first test detailed by NASA was completed in August, which the agency said demonstrated a vacuum-optimized Raptor can be started in the extreme cold conditions from extended times in space, such as those on a mission to the Moon.
“One challenge that differentiates Artemis missions from those in low Earth orbit is that the landers may sit in space without firing for an extended period of time, causing the temperature of the hardware to drop to a level below what they would experience on a much shorter low Earth orbit mission,” the Sept. 14 NASA blog update reads.
The agency also detailed a test that occurred in November 2021, which saw a Raptor firing for 281 seconds on a test stand to demonstrate its ability to perform the powered descent portion of a Lunar Starship’s trek to the Moon’s surface.
“The test had two goals: to show Raptor’s ability to change the level of engine power over time, known as its throttle profile, and for the engine to burn the full length of time of the powered descent phase,” NASA’s update reads. “The successful test provided NASA with early confidence in the company’s engine development.”
On the same day, SpaceX released video tests on social media.
Raptor engine demonstration of a descent burn to the lunar surface pic.twitter.com/MbW19KFm2H
— SpaceX (@SpaceX) September 14, 2023
In April 2023, SpaceX performed the first integrated flight test of the entire Starship launch system stack at its test facility in South Texas. While it gave the company a lot of valuable data, the flight was terminated some four minutes after liftoff after it began to veer out of its planned trajectory.
SpaceX has since made a number of upgrades to both the ground infrastructure and rocket, including 63 “corrective actions” identified in a mishap report for the first flight. Starship’s second integrated flight test could occur as early as next month, pending regulatory approval and licensing from the FAA.

The hardware for the second Starship integrated flight test is stacked at the company’s South Texas launch facility. Credit: SpaceX
Derek Richardson
Derek Richardson has a degree in mass media, with an emphasis in contemporary journalism, from Washburn University in Topeka, Kansas. While at Washburn, he was the managing editor of the student run newspaper, the Washburn Review. He also has a website about human spaceflight called Orbital Velocity. You can find him on twitter @TheSpaceWriter.