 The first phase of the ExoMars mission blasted off today with the launch of a Russian proton rocket from Kazakhstan. The vehicle sent two robotic spacecraft racing towards the Red Planet, where they're expected to arrive in October of this year. ExoMars is a joint partnership between the European Space Agency and the Russian Federal Space Agency, or Roscosmos. The main goal? Figuring out if Mars could ever have been home to alien life. To do that, the ESA and Roscosmos are sending three spacecraft to Mars on two separate missions. That includes today's launch and one in 2018. The first spacecraft on board this morning's rocket was the Trace Gas Orbiter, which will revolve around Mars and sniff out traces of methane in the atmosphere. Much of the methane in our planet's atmosphere comes from the breakdown of organic material, so its presence on Mars could be a big indicator of biological life on the surface below. Whether or not methane exists on Mars has been a hotly debated topic, so the Trace Gas Orbiter could provide some clues. The spacecraft will enter Mars' orbit in October, but it'll be a while before we know what it finds. That's because the probe needs over a year to slow down to reach the right speed for orbit, a process known as aerobraking. The orbiter will start looking for methane in December of 2017, but even if the spacecraft does find methane, it doesn't definitively prove that there is life on Mars. That's why today's launch included the Schiaparelli lander. This probe will attempt to land on the surface of the Red Planet in October. It's meant to test out the technologies needed to land the Martian rover that will be launched for the 2018 ExoMars mission. That rover is designed to take samples from the Martian surface and then analyze them while on the planet. If the ExoMars mission does uncover evidence of life, it could inspire a future Mars sample return. That involves sending a probe to collect samples from the Martian surface and then transporting them back to Earth. Such a mission would be a massive undertaking, requiring a lander, a rocket that can take off from Mars, and a vehicle that can safely transport the samples back home. But studying Martian samples in Earth labs could tell us way more about what lurks on our planetary neighbor.