In 2004, Rosetta the spacecraft and Philae the robot set out on a mission to catch a distant comet called 67P/Churyumov-Gerasimenko.<br /><br /> What they are now doing over a decade later is re-writing, in surprising new ways, our understanding of how the solar system formed.<br /><br /> Last November, after spending years chasing the comet, Rosetta finally dropped Philae onto its surface to study it more closely.<br /><br /> It was the first time a man-made object landed on a comet. Comets are of huge interest to scientists because, to human knowledge, they are the most ancient bodies of the solar system – the building blocks from which our sun and planets were formed some 5 billion years ago.<br /><br /> The Rosetta mission has been full of surprises – from the odd shape of comet 67P Philae’s unintended bounce towards a location where it could not easily recharge its solar-powered batteries. <br /><br /> The tired little lander went to sleep in November and scientists have since been struggling to determine its exact location. <br /><br /> P
