NASA is now accepting applications for its astronaut program, and the position is open to all qualified U.S. citizens.
The application period is set from December 14, 2015 to February 18, 2016. NASA hopes to announce the new astronauts in mid-2017. Potential astronauts could be flying on the International Space Station (ISS), two new commercial spacecrafts, and NASA's Orion deep-space exploration vehicle.
"This next group of American space explorers will inspire the Mars generation to reach for new heights, and help us realize the goal of putting boot prints on the Red Planet,” said NASA Administrator Charles Bolden. “Those selected for this service will fly on U.S. made spacecraft from American soil, advance critical science, and research aboard the International Space Station, and help push the boundaries of technology in the proving ground of deep space."
Think you've got what it takes? Applicants must have a minimum of a bachelor's degree in engineering, biological science, physical science, computer science, or mathematics; 20/20 vision—glasses and LASIK are okay though; and three years of related, professional experience. The latter can be sometimes be substituted by an advanced degree or 1,000 hours of pilot-in-command time.
Applicants should be ready for a long-term adventure, as NASA states that one mission can last from three to six months, and training for those missions can take two to three years. Trainees should expect "extensive travel, including long periods away in other countries training with NASA's international partners."
You can find the application on the USAJOBS site.