On Oct. 19, 2016, the European Space Agency's ExoMars mission arrived at Mars! ExoMars 2016 consists of the Trace Gas Orbiter and the Schiaparelli lander. The orbiter and lander traveled there together and separated on Oct. 16, three days before the orbiter entered orbit around Mars, and the lander touched down on the planet's surface. But something went wrong during the lander's descent, and it crashed into the ground. Schiaparelli did not survive the accident, but the Trace Gas Orbiter is still functional. It is currently circling the planet, looking for methane and other gases in the Martian atmosphere that could be evidence for possible biological activity.Artist’s illustration showing the separation of the ExoMars 2016 entry, descent and landing demonstrator module, named Schiaparelli, from the Trace Gas Orbiter, and heading for Mars. (Image credit: ESA)Why it matteredExoMars 2016 was a landmark mission for the European Space Agency and designed to be the vanguard of a two-flight ExoMars program to send an orbiter, lander and rover to Mars. Launched in March 2016, ExoMars 2016 aimed to achieve two goals for ESA and Russia. First, the mission aimed to use the Schiaparelli lander to test landing techniques that would be vital on a planned ExoMars 2018 rover. Second, the mission would deliver a critical orbiter around Mars to study the planet's atmosphere and serve as a communications link for that future Mars rover.In the end, ExoMars 2016 was just a partial success, with ESA officials calling it "96% successful." due to the loss of the lander. While Schiaparelli separated smoothly from the ExoMars Trace Gas Orbiter spacecraft, it stopped communicating with Earth just 1 minute before its planned landing on Oct. 19. Photos from NASA's Mars Reconnaissance Orbiter at Mars later revealed what appeared to be its crash site and, nearby, its jettisoned parachute. Officials suspect Schiaparelli did not fire its descent thrusters as designed in order to slow itself enough for a safe landing. A data glitch was cited as its cause.The Trace Gas Orbiter, meanwhile, continues to study Mars to this day and has spent 10 years and counting studying the Martian atmosphere. The launch of ExoMars 2018, which includes the Mars rover Rosalind Franklin, was delayed by the Schiaparelli failure, as well as the loss of its Russian Proton rocket when ESA severed its partnership with Russia over that country's war on Ukraine. The ExoMars rover is now expected to launch no earlier than 2028, with a landing on Mars expected in 2030.In 2026, another country took aim at Mars on this day. The Japan Aerospace Exploration Agency attempted to launch the ambitious Martian Moons eXploration mission (called MMX) to land a probe on the Mars moon Phobos and return samples to Earth. Want more space history? Check out our full On This Day In Space Story archive and watch our On This Day In Space videos on YouTube.