Is colonising Mars the next giant leap for humanity or is it a waste of time and money? Do humans need to be a multi planet species to avoid extinction as argued by Elon Musk? What have humans and the blue planet got to gain in the short term by practising and preparing to inhabit the Red Planet? Who better to ask than two of our favourite Martians, Australian Mars One candidate, Josh Richards and Carmel Johnston – Crew Commander of a year-long Mars Simulation mission.