This is an overview of the operations an unmanned SpaceX Red Dragon capsule will take on its mission to Mars.

1. A Red Dragon capsule, a modified and stripped-down Crew Dragon capsule, is launched atop a SpaceX Falcon Heavy launch vehicle.
2. After the Red Dragon capsule has been injected into a parking orbit, the second stage of the Falcon Heavy shuts down.
3. The second stage of the Falcon Heavy reignites for the TMI burn to send Red Dragon on a Mars-bound trajectory. Somewhere around here, Red Dragon’s nosecone is jettisoned to reduce the total mass of the spacecraft.
4. After the TMI burn is complete, Red Dragon separates itself from the second stage of the Falcon Heavy.
5. During the several-month interplanetary coast period, Red Dragon will spin on its axis, like a huge top. This is called a “barbecue roll”, and it’s done to even out the temperature differential that occurs when only one side of the spacecraft faces the sun at all times. (Read more about Orion’s barbecue roll).
6. As Red Dragon approaches Mars, it decouples its trunk. The trunk will burn up upon atmospheric entry.
7. Red Dragon orients itself heatshield-end first in preparation for atmospheric entry.
8. After atmospheric entry, Red Dragon’s onboard computers calculate the landing burn. Because of Red Dragon’s limited fuel capacity, it must perform a hoverslam.
9. Touchdown on Mars.

FAQ

Will Red Dragon carry astronauts to Mars?

No. Red Dragon’s maximum capacity is seven astronauts, and it can only support those astronauts for a very short time in LEO. Red Dragon is a stripped-down version of SpaceX’s Crew Dragon, and it cannot support passengers. Even if it could carry astronauts to the surface of Mars, it would expend all of its limited fuel in doing so, and the astronauts would have no way to return to Earth.

Why are there no fins on Red Dragon’s trunk?

Because the fins are only needed in a launch abort. Since Red Dragon is an unmanned capsule, launch abort isn’t strictly necessary; besides, unlike most missions, the Red Dragon is very mass-limited. There’s no reason to install fins on a vehicle whose mission will fail anyway during an abort.