In December 2006, Dr. Yi emerged victorious from a pool of over 36,000 candidates to become South Korea's first astronaut. On April 8, 2008, she embarked on an 11-day mission to the International Space Station (ISS) aboard Soyuz TMA-12. During her groundbreaking mission, Dr. Yi conducted numerous experiments that later contributed to South Korean science textbooks and television lectures. Her return to Earth on April 19, 2008, was dramatic; she endured a challenging ballistic re-entry and was first greeted by nomads in Kazakhstan.