While several Nasa missions have involved mixed crews, a secret report by the space agency suggests that missions to Mars could be all-female. Speaking at a conference today, British astronaut, Helen Sharman, claimed that Nasa has filed a report that warns that male and female astronauts could get frisky during the one and a half year journey to the red planet. The report claims that all-female crews would be the best option, as women work better as a team, and are less likely than men to fight over who is the leader. Ms Sharman has never seen the report herself,...