Mars is ingrained in our culture, from David Bowie's extra-terrestrial spiders to H.G. Wells's The War of the Worlds. The red planet has inspired hundreds of scientists, authors and filmmakers - but why? What is it about this particular planet that makes it so intriguing? Ancient mythologies defined Mars as a violent harbinger of war, and astrologers found meaning in the planet's dance through the sky. Stargazers puzzled over Mars's unfamiliar properties; some claimed to see canals criss-crossing its surface, while images from early spacecraft showed startling faced and pyramids carved out of rusty rock. Did Martians exist? If so, were they intelligent, civilised beings? We now have a better understanding of Mars: its red hue, small moons, atmosphere (or lack of it), and mysterious past. Robots have trundled across the planet's surface, beaming back astonishing views of the alien landscape and seeking clues on how it has evolved. While little green Martians are now firmly the preserve