SpaceX has conducted its first firing test of its Raptor engine, the powerful propulsion system that the company aims to use to take humans to Mars. SpaceX boss Elon Musk tweeted pictures of the tests late last night, sharing one image that showed a steady stream of flame emanating from the engine, and another showing "Mach diamonds" — patterns formed in the exhaust plumes of supersonic craft.

Musk has been has been fairly vague on Raptor specifications so far, but tweeted a few extra details after last night's tests, confirming production goals and chamber pressure. Previously the SpaceX CEO has indicated that Raptor engines will deliver about 500,000 pounds of liftoff thrust — about as much as the Space Shuttle's main engines — and will use liquid methane rather than kerosene. Full-scale Raptor engines first arrived at SpaceX's testing facility in McGregor, Texas, earlier this year, but lots still isn't known about the technology, including how many will be used to launch SpaceX's interplanetary spacecraft, the BFS.

SpaceX propulsion just achieved first firing of the Raptor interplanetary transport engine pic.twitter.com/vRleyJvBkx — Elon Musk (@elonmusk) September 26, 2016

There's no set date for SpaceX's crewed mission to Mars, but Musk has repeatedly stated that he wants to send the first people to the Red Planet by 2024. Paving the way for people will be a series of missions, slated to begin in 2018, that aim to drop supplies down to the surface of our planetary neighbor. That doesn't give SpaceX much time to work out how to colonize a world, but assuming last night's Raptor tests went well — and if the company can avoid future mishaps on the launchpad — then Musk's ambitious schedule may indeed work out as intended.

SpaceX trip to Mars simulation