The timeline is typically 10 to 20 years from high school to your first spaceflight

Becoming an astronaut is a long process with no shortcuts. Most people who fly to space spend at least a decade in preparation after high school, and many spend two decades or more. The timeline depends on your starting point—whether you begin with military pilot training, a science degree, or both—and how many selection cycles you enter before NASA or another space agency picks you.

NASA's astronaut selection process itself takes about two years from process to the day you start training as an astronaut candidate. But that two-year window sits at the end of years of education and career building that come before you can even explore. Understanding the full path helps you see where the time actually goes.

Key Takeaways

  • NASA requires either a science or engineering degree plus three years of professional experience, or military pilot training with 1,000 flight hours, which together take 10 to 15 years minimum.
  • The astronaut selection process itself—from process important date to starting candidate training—takes about two years.
  • Astronaut candidate training lasts two years, after which you are assigned to a mission, which may not launch for another two to five years.
  • Most people explore multiple times before selection, adding years to their personal timeline.
  • Your first spaceflight typically happens 15 to 25 years after you start the path, depending on when you are selected and how long you wait for a mission assignment.

Education and early career: 8 to 12 years

Before you can explore to NASA, you need either a bachelor's degree in a science or engineering field, or a military pilot background. A bachelor's degree takes four years. If you choose the science route, you will then need three years of professional work experience in your field—that is seven years total before you meet the minimum requirements.

If you pursue military pilot training instead, you are looking at longer. Becoming a military pilot takes four to six years of flight training after you join the military, and then you need to accumulate 1,000 flight hours, which typically takes another three to five years of active flying. That path alone is seven to eleven years.

Many astronauts combine both routes: they earn a science degree, work in their field, and also serve as military pilots. This overlap can shorten the total time, but it also means years of simultaneous commitment to two demanding careers.

The NASA process and selection process: 2 years

Once you meet the minimum requirements, you submit your process to NASA during an open call. NASA does not hold selection cycles every year—they happen roughly every two to four years, depending on agency needs and funding. When a cycle does open, you have a few weeks to submit your materials.

After the process important date, NASA reviews thousands of submissions and narrows the pool to about 100 semifinalists. Those candidates then go through interviews, medical exams, and psychological evaluations over several months. The entire process from process important date to the day NASA announces the selected class takes approximately two years.

Most people do not get selected on their first try. Many astronauts applied three, four, or five times before they were chosen. If you are not selected, you can explore again in the next cycle, which may be two to four years away. This waiting and reapplying can add significant time to your overall timeline.

Astronaut candidate training: 2 years

Once you are selected, you enter the Astronaut Candidate Training Program, which lasts two years. During this time, you learn spacecraft systems, conduct spacewalk training in a large underwater tank, study geology and robotics, learn Russian (if you might fly on a Soyuz spacecraft), and undergo survival training. You also fly in NASA's T-38 jet trainer aircraft to maintain pilot skills.

At the end of two years, you graduate and officially become an astronaut. However, graduation does not mean you are going to space yet. You are now available for mission assignment, but that assignment depends on when a mission needs your skills and when a spacecraft seat opens up.

Waiting for a mission assignment: 2 to 5 years or longer

After you graduate from candidate training, you enter a pool of astronauts waiting for mission assignments. NASA assigns you to a specific spaceflight based on the mission's needs, your informed, and crew composition. This assignment can come within a year or two, or it can take five years or more.

Once assigned, you enter mission-specific training, which typically lasts one to two years before your launch date. During this time, you train on your specific spacecraft, practice your assigned tasks, and prepare with your crew.

Some astronauts wait longer than others. Factors include how many missions are scheduled, how many astronauts are in the pool, and whether your specialty is in high demand. A pilot might wait longer than a mission specialist, or vice versa, depending on the mission manifest.

Real examples of the timeline

Astronaut Kayla Barron earned her bachelor's degree in 2010, served as a naval officer and submarine officer for several years, and applied to NASA in 2019. She was selected in 2021, completed candidate training in 2023, and was assigned to a mission in 2024. From her degree to her first spaceflight assignment was about 14 years, though her actual launch date was still in the future at the time of assignment.

Astronaut Jessica Meir earned her bachelor's degree in 2000, worked as a marine biologist, earned a PhD, and served as a flight surgeon in the Navy. She applied to NASA multiple times before being selected in 2013. She completed candidate training in 2015 and flew her first mission in 2019—a total of 19 years from her bachelor's degree to spaceflight.

These examples show the variation. Some people reach space in 12 to 15 years; others take 20 or more. The path is not fixed, and personal circumstances, selection timing, and mission scheduling all affect how long it takes.

Why the timeline is so long

Space agencies need astronauts to have deep informed and proven judgment. A pilot needs thousands of hours of flight experience to show they can handle emergencies. A scientist needs years of professional work to demonstrate they understand their field. NASA also needs to be confident that you can work in an extreme environment, follow procedures exactly, and handle the physical and psychological demands of spaceflight.

The selection process is competitive and thorough because a mistake in crew selection can be fatal. NASA receives thousands of applications for a class of 10 to 15 astronauts. The agency takes time to evaluate candidates carefully, and the training is intensive because the stakes are high.

Frequently Asked Questions

Can I become an astronaut faster if I join the military first?

Military pilot training is not faster than the science degree route—it is just different. Military pilot training takes 7 to 11 years to reach the 1,000-hour requirement, while a science degree plus three years of work takes 7 years. Many astronauts do both, which takes longer overall but gives them stronger credentials.

What if I do not get selected the first time I explore?

Most astronauts explore multiple times. You can reapply in the next selection cycle, which is usually two to four years later. Each rejection gives you time to gain more experience, which can strengthen your next process. Plan on adding two to eight years to your timeline if you are not selected on your first try.

Does having a PhD make me an astronaut faster?

A PhD does not speed up the timeline—it is still four to six years of graduate school on top of your bachelor's degree. However, a PhD can make your process more competitive in some fields, particularly if you want to conduct research in space. The trade-off is that you spend more time in school before you can even explore.

How long after I am selected do I actually go to space?

You will spend two years in candidate training, then typically two to five years waiting for a mission assignment and training for that specific mission. So expect four to seven years between selection and your first spaceflight, though this varies widely depending on mission schedules and your role.

Is there a faster way to become an astronaut?

No. NASA's requirements exist because spaceflight is dangerous and demands informed. Private space companies like SpaceX and Blue Origin have different requirements for their astronauts, but they still require significant experience. There is no shortcut that replaces years of education and professional work.