Space is notoriously dangerous for astronauts, but the first astronauts who return from the moon or Mars may be a danger to all life on earth. The exotic microorganisms that they bring with them may become man's deadliest ene mies, warns a panel of eminent scientists headed by Biologist Allan H.
Brown of the University of Pennsylva nia. The panel's report, "Potential Haz ards of Back Contamination from the Planets," was made public last week after nearly a year of hush-hush treatment by the National Aeronautics and Space Administration. It added a chill ing new factor to the future of...