Introduction: International Astronomy Day is an annual event that celebrates the wonders of the universe and promotes the science of astronomy. This day brings together people of all ages and backgrounds to explore the cosmos, learn about celestial objects, and appreciate the beauty of the night sky. In this research paper, we will explore the history, significance, and activities associated with International Astronomy Day. History: International Astronomy Day was first established in 1973 by Doug Berger, an American high school teacher. His aim was to foster an appreciation for astronomy and to encourage public interest in the field. Over the years, this event has gained popularity worldwide and is now celebrated on various dates, often in the spring or autumn, depending on local preferences and astronomical events. Significance: Astronomy is the scientific study of celestial objects such as stars, planets, galaxies, and the universe as a whole. International Astronomy Day plays a cr