Elon Musk tweeted on Thursday that his company’s Raptor engine has “achieved power level needed for Starship and Super Heavy.” The Starship is the rocket that Musk ultimately hopes to propel people to Mars. The Super Heavy is the booster that will also play an integral role in the trip to Mars. The Starship is expected to have seven Raptor engines attached to it and the Super Heavy will have 31 Raptor engines.

The Raptor engine is the critical component in fulfilling Musk’s dream of getting to Mars. It’ll be the most powerful engine SpaceX has ever built. According to Musk, the test hoped to see the engine achieve 170 metric tons of force. It was able to hit 172 metric tons. He added that the engine should be able to achieve even greater force in the future.

Raptor just achieved power level needed for Starship & Super Heavy pic.twitter.com/NcqnAVWc35

— Elon Musk (@elonmusk) February 7, 2019

Now that SpaceX has overcome that hurdle, the company needs to continue to test the engine and extend its time running to ensure it can work for an eventual trip to Mars. In a page on its website detailing the Mars mission, SpaceX says that it hopes to send the first cargo mission to Mars in 2022. A mission with cargo and humans could take flight in 2024.