The Netherlands-based Mars One organization this year announced plans to send four astronauts to Mars by 2023, with four additional 'crew' arriving every two years. The kicker? They won’t be coming back. Mars One says the crews will spend the rest of their lives living and working on Mars. “While sustaining human life on Mars is not trivial, it is far easier and safer than bringing the crew back to Earth. If the astronauts had to return to Earth after their visit to Mars, a fully functional and fueled return rocket would have to be constructed on Mars without any human supervision, which is extremely complex and expensive. Instead, Mars One will provide the first and subsequent crews with water, food and oxygen by mining...