Throughout this course, we have described space is challenging because it is. Hopefully for those of you who have dreamed of one day being an astronaut, we haven't dampened your hopes. Instead, we have painted a much more detailed picture of life in space. The good news is, despite all of these problems, humanity has already come together on numerous occasions to overcome many issues and has already set numerous journeys into space. In this last lesson, we'll review the requirements to become a NASA astronaut and appreciate why with everything we've learned, they are so tough. To begin, the odds of becoming an astronaut are astronomical. In 2017, over 18,300 people applied to be NASA astronauts. From that list, 12 people were selected for the job. Even with all of the qualified candidates, they are tough odds. However, in gaining the necessary skills and experience to become an astronaut, anyone can live a fantastic life regardless of that final selection decision. Our first requirement is that there is a physical standard that astronauts must meet. This includes: exercise, eyesight, and hearing test. We have mentioned that you need to exercise two hours a day to mitigate bone and muscle atrophy and that space still takes a toll. These health requirements also ensure that there is a low chance of experiencing a medical emergency and lower mission risk. If you're set on becoming an astronaut, living a healthy life with plenty of strength-based and cardiovascular exercise is important. Of course, for everyone, some exercise is important. A second requirement is a relevant scientific background and/or experience as a pilot. Much like making decisions on which equipment to bring, mission controllers need to be deliberate in selecting the few people that travel to the International Space Station, to the moon in the Artemis missions or for the first missions to Mars. With every additional person, we can bring a new expertise and set of skills. But each person also requires a full supply of food, water, space suits, and everything else needed for the trip. Thus, it is especially important that people who have the interests and skills for developing a settlement on Mars are selected. Hopefully, at the end of this course, you'll appreciate that a doctor is a vital role and should have a spot in the crew. Likewise, you'll need a pilot to operate the various spacecraft and vehicles on Mars. Settling the moon on Mars would require a geologist and botanist to maintain the first farms, chemists, and physicists to understand how the different gravity, radiation, and elements on Mars affect the crews, and computer scientists and engineers to set up and repair the technology that is needed. Specifically, because of the large number of applicants, NASA wants to see at least a master's degree in a scientific field and two years of relevant experience. If you're trying to maximize your chances and want to know which branch of science is best, there's no right answer. The most important thing is that you're passionate about the subject. NASA astronauts have experience in medicine, biology, chemistry, geology, engineering, physics, computer science, and mathematics. Passion will make your application shine to NASA. Also, if you're not selected as an astronaut, you'll still be able to work in a field of your interest. The last rule for NASA is that you need to be a US citizen. Even if you find yourself lacking some of these requirements, there's still hope. As more countries, organizations, and companies push humanities reach in space further, more people have access. As technologies improve, it will be less expensive to put humans into space and less necessary that everyone selected have perfect health and a scientific background. If your application is then considered for the next round of selections, personality becomes important. Specifically, focus and being a team player in the instrumentality and expressivity dimensions is heavily rewarded. Mission controllers and current astronauts will want to know if you'll be able to get along with a few other humans in a small spacecraft for months or years. It's unsurprising then that on top of being incredibly accomplished and intelligent, astronauts are nice, hardworking, and passionate individuals. This is especially important because NASA astronauts are public personalities and you'll be representing the United States when there are cameras and people watching from back on Earth. After understanding this whole process, astronauts care about humanity and doing a dangerous job. They're advancing science and our understanding of the world. Despite the threats represented by deep space travel, they are ready to brave the unknown and settle the final frontier.