While speaking at the Royal Aeronautical Society in London in November, the billionaire former Paypal Internet executive, Tesla electric car entrepreneur, and current Space Exploration Technologies (SpaceX) CEO and self-taught lead rocket engineer, Elon Musk, described his plan to enable a self-sustaining human colony on the planet Mars. This plan is to use reusable rockets and along with Mars landing and ascent craft to take mankind to Mars within 15 years. And to do it Musk announced that liquid oxygen (Lox) and Methane would be SpaceX’s principal propellants of choice.