We know what SpaceX's next-generation Starship looks like. Now we've also got a new look at the Raptor engine that will one day rocket it off our planet -- and a sublime display from its first test firing, too.

Elon Musk posted a pair of images to Twitter late Thursday showing a Starship Raptor engine and saying SpaceX is preparing to fire it at its Texas facility. One of the images shows a worker standing near the engine, giving us a good sense of its scale.

The Raptor has been under development for years, but Musk said in December the latest version is "radically redesigned." Musk spilled a few geeky details on the test engine's thrust and how it's geared toward reaching the moon as fast as possible.

The moon goal is an important one. SpaceX and Musk announced last year that Japanese billionaire Yusaku Maezawa had bought up all the seats for a planned 2023 Starship mission to travel around the moon.

Musk says Starship will eventually have seven of the new engines. SpaceX currently has a "hopper" prototype of the stainless-steel Starship meant for takeoff and landing tests, with hopes of unveiling an orbital version by midyear.

Musk has been openly engaging with SpaceX fans on Twitter. One asked if he's finding rocket engine design easier or harder over time. "Well, my past mistakes do seem extremely dumb, especially the ones where I mistakenly thought I was smart," Musk replied.

Starship is meant to eventually be paired with a Super Heavy rocket, formerly known as the Big Falcon Rocket (BFR). Super Heavy will use up to 31 Raptor engines, though Musk says initial tests will probably involve fewer engines "in case it blows up."

Musk also uploaded a couple of videos of the test firing to his Twitter account on Feb. 3 and, it goes without saying but, you would not want to be standing behind this thing when it is ready to blow.

Musk envisions a future where Starship is able to carry humans all the way to Mars and help establish an outpost on the red planet. 

SpaceX suffered a setback in January when high winds in Texas toppled the nose cone off the Starship prototype. Musk said at the time it'd take several weeks to repair the damage.

In the meantime, Musk has dropped insider looks at heat-shield testing and now the Raptor preparations, showing that development on Starship is moving ahead at a rapid pace.

SpaceX will need to keep the rocket pedal to the metal if it wants to make its proposed 2023 date with the moon.

First published Feb. 3, 11:45 a.m. PT
Update, 8:09 p.m.: Adds test firing images and videos from Musk's Twitter account

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