SpaceX has just completed its first test fire of a full-scale Raptor engine, which will be used to power the company’s next generation rocket. The news was announced by SpaceX CEO Elon Musk, who posted a pair of videos on Twitter of the engine being test fired at the company’s test sight in McGregor, Texas. The Raptor engine is currently being developed as a successor to the company’s existing Merlin 1D engine, and is expected to eventually power the company’s Starship to the Moon, to Mars, and beyond.

Musk posted two videos of the tests, one without sound and one with so much that it’s worth turning your speakers or headphones down before watching it. Three such engines are expected to be installed on the company’s prototype Starship, which will perform short “hop” tests up to low altitudes of between 1,640 and 16,400 feet. Eventually, however, the plan is for the final Starship to have a total of seven Raptor engines, along with a further 31 in the Super Heavy booster that will carry the Starship to space.

In a follow-up tweet, Musk explained that the green tinge in the video above could be the result of copper in the chamber, or else simply saturation of the camera.

Although we saw our first test of these engines way back in 2016, this latest test uses a full-scale engine that Musk called “radically redesigned.” Unlike conventional rocket engines, the Raptor primarily uses methane as fuel, which the company has claimed gives better performance than other systems. It’s also cleaner, lower cost, and could even be harvested on Mars to refuel the engine away from Earth. Eventually, each Raptor is intended to provide around 440,000 pounds of liftoff, compared to 190,000 for the current Merlin engines.

On January 5th, the SpaceX CEO said that the hope was to start performing test flights of the Starship within four to eight weeks. However the Starship prototype SpaceX has been building was badly damaged by strong winds in Texas, which will likely delay the vehicle’s first test flights.

Eventually, Musk has said that that he hopes that the new rocket could perform an uncrewed mission to Mars as early as 2022, with a crewed flight to follow in 2024. However, considering the CEO’s history of optimistic deadlines it’s best to view these plans as an aspiration, especially considering that the cost of these projects recently caused SpaceX to lay off 10 percent of its workforce.