"100 HOURS of Astronomy" was held in front of the Centennial Hall on April 2. As 2009 is designated as the "International Year of Astronomy," Korean organizing committee of International Year of Astronomy 2009 (IYA 2009) authorized Yonsei Univ. to prepare for the festival, which took place on about 130 countries all over the world. Students in the Dept. of Astronomy have made observations of the sun and stars, prepared the images of observatories carried live from various countries, and so on. Kim Sang-hoon (Jr., Dept. of Astronomy), the student director of "100 Hours of Astronomy," said, "As the universe is the least discovered area, I want all Yonseians to become curious about the unknown space through this event."