The Case for Mars is not a vision for the far future or one that will cost us impossible billions. It explains step-by-step how we can use present-day technology to send humans to Mars within ten years; actually produce fuel and oxygen on the planet's surface with Martian natural resources; how we can build bases and settlements; and how we can one day "terraform" Mars - a process that can alter the atmosphere of planets and pave the way for sustainable life.