Sending humans to Mars has always seemed a distant dream. But in recent years, cheap access to space, the steady arrival of Mars rovers to explore the surface and the ambitions of billionaires like Elon Musk have made the Red Planet feel almost within reach.
All concerned are aware of the huge challenges — from developing the technology to support life during the journey and to safely deliver them to the surface, to bringing them home again. This will be one of the greatest expeditions in human history.
But there is another challenge beyond that is of even greater proportions — the task of colonizing the Red Planet once we get there. Colonization is crucial, say proponents, to create a technology goal for humanity to work towards, to give us greater insight into the nature of the Solar System and ultimately, to create a back-up should we destroy the climate on Earth.