Elon Musk and SpaceX's ambitious plans to reach around the moon and all the way to Mars require a big effin' rocket. Now we know what it looks like.

Musk tweeted out an image on Thursday of an assembled early version of the SpaceX Starship, which was once known in polite company as the Big Falcon Rocket. 

"Starship test flight rocket just finished assembly at the @SpaceX Texas launch site. This is an actual picture, not a rendering," Musk wrote. 

He first teased us in December with an image of the prototype rocket under construction.

The assembled version looks like a stainless-steel Airstream trailer mated with a space shuttle. A person or mannequin in a spacesuit stands nearby to give us a sense of scale. Starship is a monster.

Musk dropped a few more details about the prototype: "This is for suborbital VTOL tests. Orbital version is taller, has thicker skins (won't wrinkle) & a smoothly curving nose section." VTOL stands for "vertical take-off and landing." Musk says the body diameter of Starship is about 30 feet (9 meters).

The SpaceX founder also retweeted a video taken by Twitter user Evelyn Janeidy Arevalo showing the rocket as seen out of a car window driving by.

Musk says the first Starship orbital prototype should be done around June. The current version will be used for short "hopper" flights that send it up and then bring it back down to test launch and landing systems.

The entrepreneur has big plans for Starship. SpaceX already sold out a voyage around the moon with a hoped-for launch date in 2023. It will be interesting to follow along as Starship moves toward actual space travel.

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