The spaceways to Mars are littered with the debris of probes trying reach the dusty red planet's surface. In 55 years of Mars exploration, no space agency in the world other than NASA has ever landed a probe on the surface of Mars that survived more than a handful of seconds.

NASA's success in putting a sequence of increasingly larger and more complex spacecraft onto the surface of Mars, culminating with the 1-ton Curiosity rover in 2012, has been rather remarkable in comparison to other space agencies. Eight of NASA's nine missions to the surface of Mars have been successful, with only its Mars Polar Lander failing to safely reach the surface in 1999.

By contrast, four of five Soviet Union landers failed to reach Mars safely, and the one that did, Mars 3 in 1971, survived for only about 15 seconds. In addition there have been a number of failed Soviet and Russian attempts to reach the Martian moon Phobos.

Europe also tried to land a spacecraft on Mars just once, in 2003, when contact with the Beagle 2 was lost during a landing attempt. Scientists believe two of its solar panels may have failed to deploy. All of this international failure ratchets up the pressure on the European Space Agency after the first of its two ExoMars missions successfully launched this morning from Baikonur, Kazakhstan aboard a Russian Proton rocket.

B. Bethge/ESA

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The European Space Agency's ExoMars program represents a multi-pronged approach to better address the question of whether life ever existed on Mars. The "Exo" part of its name stands for exobiology. Monday morning's launch is the first step, with the launch of two elements—the Trace Gas Orbiter and Schiaparelli—an entry, descent, and landing demonstrator module.

The second, more ambitious component of the ExoMars program is planned for launch in 2018 and comprises a rover and surface science platform. This lander will include a rover with a drill capable of extracting samples from as deep as 2 meters and an infrared spectrometer to analyze the drill samples. This analysis will include a scan for potential organic substances.

But today's mission must first be a success. The Trace Gas Orbiter has been designed for a five-year operation to map the distribution of methane and other trace gases throughout the Martian atmosphere. If any life exists on Mars today it likely would produce methane. This spacecraft will also serve as a data relay for the ExoMars 2018 rover as well as, potentially, NASA rovers.

The orbiter's traveling companion, the Schiaparelli lander, will separate from the orbiter about seven months from now, three days before reaching the Martian atmosphere. Then, on October 19, the 1.65-meter lander will make its approach to the red planet at a speed of about 21,000km/h. From an altitude of 121km down to 11km the spacecraft's heat shield will char and ablate, slowing the spacecraft to 1,700km/h and allowing for a parachute to deploy.

As it nears the ground, nine hydrazine-powered thrusters will fire to control its speed down to a few meters per second, and a crushable structure will absorb the impact force. Once on the surface, the probe's limited scientific package is designed to operate for a few days. The primary role of Schiaparelli will be to demonstrate this landing technology, so that the 2018 mission with the rover can also safely reach the Martian surface.

The ExoMars program has been in various stages of planning since around the turn of the century. In 2008 NASA and the European Space Agency reached an agreement to share costs on the two missions, an orbiter and landers, that would both search for life and test technologies for a mission to return samples of Martian soil and rocks to Earth.

However, in February, 2012, President Obama's budget called for the cancellation of NASA's participation in the program to pay for the James Webb Space Telescope, which continued to run over its budget allocation. "Tough choices had to be made," NASA's administrator, Charles Bolden, said at the time about the agency's science budget.

At that point the European Space Agency turned to Russia, which has long wanted to return to Mars after a series of missions in the 1970s. The Russian Space Agency agreed to provide Proton rockets for both the 2016 and 2018 launches, as well as some scientific instruments for the 2016 orbiter. The Russians will also assist with the development of technology for the 2018 rover.

And so today's launch was neither the beginning nor the end of efforts by Europe and Russia to finally put a robust lander safely on the surface of Mars. It is but a step, with the bigger tests coming later this year with the Schiaparelli landing, and in 2018, when a highly capable rover tries to repeat this feat.