"Living for two years within a sealed ecological system known as Biosphere 2 – which was described as one of the most exciting scientific projects since the first moon landing – changed everything about the way its human inhabitants related to the Earth as a support system for all life. "It is now 25 years since they stepped across the threshold in Arizona and to celebrate that rite of passage and all that has unfolded since, a trio of Biospherians and their supporters have created a … Watch video