What Does It Take to Be a NASA Astronaut?

For many aspiring space explorers around the world, becoming an astronaut is a childhood dream. Recently, a record-breaking 18,300 people attempted to realize that dream by applying for NASA’s 2017 Astronaut Candidate program. What does it take to be selected as a NASA astronaut? VOA's Peggy Chang and Shan Xu went to NASA’s Johnson Space Center near Houston to find out about the selection process.