On 6 December 2016 the United Nations General Assembly (UNGA) proclaimed in resolution A/71/492 that International Asteroid Day (IAD) will be observed annually on 30 June to raise public awareness about the asteroid impact hazard. June 30 is the anniversary of the Tunguska impact over Siberia, Russian Federation, on 30 June 1908. The Tunguska asteroid event was the Earth's largest asteroid impact in recorded history.
International Asteroid Day will encourage reflection on the impact hazard of asteroids and the global work undertaken in this area and facilitated by UNOOSA, including work by the Committee on the Peaceful Uses of Outer Space (COPUOS) and its Member States, the Space Mission Planning Advisory Group, and the International Asteroid Warning Network.
All United Nations Member States, organizations of the United Nations system, other international and regional organizations, as well as civil society, including non-governmental organizations and individuals, are invited to observe International Asteroid Day.
The UNGA's decision was made after a proposal by the Association of Space Explorers, which was endorsed by COPUOS.