Six thousand people applied for the NASA astronaut corps. The year-and-a-half training program, which started in 2013, included a series of intensive physical and psychological tests. Eight were finally selected and four of them were female -- Christina Hammock Koch, Nicole Aunapu Mann, Anne McClain, and Jessica Meir. It is the first time that a class of astronauts has been equally split down gender lines.
"We never determine how many people of each gender we're going to take, but these were the most qualified people of the ones that we interviewed," explains Janet Kavandi, the deputy director of NASA’s Glenn Research Center. It is the first astronaut class being trained for a crewed mission to Mars. Astronaut McClain says: “If we go to Mars, we'll be representing our entire species in a place we've never been before. To me it's the highest thing a human being can achieve.”The BEST SALES on Amazon NOW ]