More than a decade's worth of work is tucked inside the body of this Russian Proton-M rocket: the Trace Gas Orbiter (TGO) and the Schiaparelli EDM lander. The rocket, having just been fueled, was moved to the launch pad at the Baikonur Cosmodrome in Kazakhstan on March 10, 2016, where it was raised upright. Historically, the Proton rocket has a failure rate of 10 percent.

Hours after the launch, the orbiter (black) and lander (gold) will emerge from the rocket's shell. Thus begins their seven-month journey to Mars. The Earth-Mars orbital alignment is favorable to this portion of the ExoMars mission, meaning the journey is a relatively short one.

Having accompanied each other through empty space for more than 200 days, the lander and orbiter will detach from one another three days before reaching Mars. The time is late October. For the rest of their robotic lives, they're on their own.

And the lander's off! At this point it's traveling at more than 20,000 kilometers per hour (12,500 miles per hour, or about 3 miles per second). Its destination is predetermined: Meridiani Planum, a flat, broad plain rich in hematite, which on Earth is often formed in hot springs. Things are about to get hot...

Mars' atmosphere will "drag" or slow the lander, allowing it to deploy a parachute (model seen here) to reduce its velocity to roughly 200 kilometers per hour (120 MPH). When its height above the surface reaches 1.2 kilometers, the cord will sever and the lander will deploy thrusters to slow its descent and land.

Once on Mars, a variety of instruments inside the lander will collect various atmospheric data over a period of four days. This will give Europe's and Russia's space agencies critical information for a future rover landing. When the four days are up, Schiaparelli's battery will run out. Its mission is over.

Meanwhile, the orbiter will still be scooting around up above. The jets seen here will only be deployed initially - to change an elliptical orbit into a circular one.

At that point, the orbiter's job for the next few years will be to "sniff" Mars' atmosphere for traces of methane gas. Scientists in Europe and Russia will be analyzing this data to determine the best spot to aim their rover. Methane could be a clue to biological activity - a sign of life on Mars.

A 2018 follow-up launch will send the ExoMars rover toward a predetermined point on the red planet - likely Oxia Planum, which is 3,000 meters below the Martian mean and which is rich in iron-magnesium. That means water might have played a role there. See that dark gray cylinder on the front...?

That's the drill that will collect "cores" of Martian soil (prototype above). The hope is that when it's analyzed inside the machine through an organic molecule analyzer, it will yield signs that biological activity once occurred there. The earliest that would happen is 2019 (and maybe 2021). But it would be enormously historic. It would be the first direct evidence of life on Mars.