NASA is accepting applications for new astronauts from Dec. 14 through the middle of February 2016.

NBC News reports that a statement was issued by NASA administrator Charles Bolden on Wednesday that said the new group of astronauts will help “realize our goal of putting boot prints on the Red Planet.” The statement also says those selected will “fly on a U.S made spacecraft,” “research aboard the International Space Station” and advance technology in deep space.

SpaceX and Boeing are building future spacecraft that NASA hopes to use to send astronauts to the International Space Station, starting in 2017. A crewed launch has not taken place in America since the space shuttle program was shut down in 2011.

A space launch rocket system is under testing from NASA, which is designed to take astronauts to deep space, specifically Mars, inside the Orion capsule. 47 members of NASA’s astronaut corps are active, but more are needed for future missions.

In order to become an astronaut, a candidate must have a bachelors degree in biological science, physical science, engineering, or math. Alternatively, 1,000 hours as a pilot-in-command or three years professional experience can put them in the running. Candidates must also pass NASA’s rigorous spaceflight physical. There is no age restriction, but on average, those selected are around age 34.

Salary for an astronaut typically starts at $66,000 a year, but can increase to as much as over $144,000, with experience.