The first International Olympiad on Astronomy and Astrophysics is to commemorate His Majesty the King's 80th Birthday and H.R.H. Princess Galyani Vadhana's 84th Birthday in the year 2007.

But it is sad that Her Royal Highness Princess Galyani Vadhana, the beloved sister of His Majesty the King, passed away at 02:54 a.m. Wednesday, 2nd January 2008 after a lengthy illness at Siriraj Hospital, the Royal Houselhold Bureau has announced.

IOAA is designed to be a truly international organization on Astronomy and Astrophysics competitions. The organization is run by an international committee, whose members are elected from international members of the organization.

The purpose of IOAA is to promote interests and educations on astronomy and astrophysics of high school students. By participating in the competitions, students will have opportunities to meet fellow students of the same interests and make friends. This will lead to good understandings among countries and hence collaboration in future researches.
IOAA organizes a yearly competition on astronomy and astrophysics for high school students. Each member "country" takes turn to host this event. The first one will be in Thailand, the second one in Indonesia, and the third one in Iran.