Ready to geek out on Mars? Carl and Richard chat about the Mars Science Laboratory's arrival at Mars. Richard digs into the history of Mars exploration, from the Mariner missions in the 1960s to the amazing Viking landers in the 1970s, and finally to the modern era with the loss of Mars Observer and the triumphs of rovers like Sojourner, Spirit, Opportunity and finally Curiosity. The conversation goes on to the future of Mars exploration - what about a sample return mission? What will it take to get humans on the surface of Mars?