When NASA sent astronauts to the moon in the 1960s and 1970s the agency excluded women from the corps, arguing that only military test pilots - a group then made up exclusively of men - had the right stuff. It was an era in which women were steered away from jobs in science and deemed too fragile for space flight. Eventually, though, NASA relented and opened the application process to everyone, regardless of race or gender. From a 1977 candidate pool of 8,000 six elite women were selected - Sally Ride, Judy Resnik, Anna Fisher, Kathy Sullivan, Shannon Lucid, and Rhea Seddon. In The Six, acclaimed journalist Loren Grush shows these brilliant and courageous women enduring claustrophobic - and sometimes deeply sexist - media attention, undergoing rigorous survival training, and preparing for years to take multi-million-dollar payloads into orbit.