We humans have not been back to the Moon because not enough of us have wanted to. Getting into space requires a lot of energy and it is just as challenging as keeping humans alive in space. Neither is impossible, but they are expensive. If we want to go back to the Moon, we have to spend the necessary money and that means we need a reason to. In the past, this might be for political reasons or for scientific ones. Now, I think, we are starting to see commercial reasons for wanting to do this. Missions such as « Lunar Mission One » are commercial, involve many people and help to stretch the imagination of individuals and organisations about what is possible.