This job opportunity is out of this world — literally. For the first time in over four years, NASA is accepting applications for its next crop of astronauts, the agency announced Monday.

Not every space hopeful will get to don the iconic astronaut suit, however. Applicants must be U.S. citizens and meet one of the stringent education requirements, which include having either a master's degree in a STEM field, a medical degree, or a combination of a STEM degree and test pilot training.

Potential astronauts must also have at least two years of related professional experience — or have completed at least 1,000 hours of "pilot-in-command time" in jet aircraft. Then they still have to pass NASA's long-duration spaceflight physical.

Applicants are required to complete an online assessment that can take up to two hours to finish. The deadline to apply is March 31.

The agency announced last month that it would begin hiring new astronauts, but just began accepting applications Monday. 

The opportunity comes as NASA moves ahead with plans to send the first woman and next man to the moon by 2024 with its Artemis program.

The Artemis mission seeks to "demonstrate new technological advancements and lay the foundation for private companies to build a lunar economy." The goal is to have humans explore the moon's South Pole surface for the first time ever and lay the groundwork for human missions to Mars later this century. 

"America is closer than any other time in history since the Apollo program to returning astronauts to the Moon," NASA Administrator Jim Bridenstine said in a press release. "We're looking for talented men and women from diverse backgrounds and every walk of life to join us in this new era of human exploration that begins with the Artemis program to the Moon. If you have always dreamed of being an astronaut, apply now."

The final astronaut candidates are expected to be selected by the middle of next year and would then begin training as the next class of Artemis Generation astronauts, according to NASA.

In 2015, when the agency was last looking for new astronauts, more than 18,000 people applied. Following over two years of "intensive training," 11 new astronauts made the cut and graduated in a public ceremony in January. A member of that class, Jonny Kim, notably became NASA's first Korean-American astronaut.

"Becoming an astronaut is no easy task, because being an astronaut is no easy task," said Steve Koerner, NASA's director of flight operations and chair of the Astronaut Selection Board. "Those who apply will likely be competing against thousands who have dreamed of and worked toward going to space for as long as they can remember. But somewhere among those applicants are our next astronauts, and we look forward to meeting you."     

NASA has chosen 350 people to train as astronaut candidates since the 1960's and currently has 48 astronauts in its "active astronaut corps."