International Asteroid Day – June 30
Near-Earth objects (NEOs) represent potentially catastrophic threats to our planet. NEO is an asteroid or comet, which passes close to the Earth’s orbit. According to NASA’s Center for NEO Studies, there are over 16 000 Near Earth Asteroids discovered. The Tunguska asteroid event in Siberia, Russian Federation, on 30 June 1908, was the Earth’s largest asteroid impact in recorded history.
In December 2016 the United Nations General Assembly adopted resolution A/RES/71/90, declaring 30 June International Asteroid Day in order to “observe each year at the international level the anniversary of the Tunguska impact over Siberia, Russian Federation, on 30 June 1908, and to raise public awareness about the asteroid impact hazard.”
On 15 February 2013, a large fireball (technically, called a “superbolide”), traveling at a velocity of 18.6 kilometers per second, entered the atmosphere and disintegrated in the skies over Chelyabinsk. According to NASA, the approximate effective diameter of the asteroid was estimated at 18 meters and its mass at 11,000 tons. The approximate total impact energy of the Chelyabinsk Fireball, in kilotons of TNT explosives (the energy parameter usually quoted for a fireball), was 440 kilotons. The Chelyabinsk event was an extraordinarily large fireball, the most energetic impact event recognized since the 1908 Tunguska blast in Russian Siberia.
The United Nations Office for Outer Space Affairs (UNOOSA) has worked on NEOs for many years, recognizing a NEO impact hazard as a global issue demanding an international response. Addressing such a hazard, including the identification of those objects that pose a threat of impact and planning a corresponding mitigation campaign, requires cooperative action in the interest of public safety on the part of the global community.