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International Asteroid Day2027 Countdown
Wednesday, June 30, 2027
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About International Asteroid Day
International Asteroid Day, observed every June 30, is the United Nations' official moment to think about the rocks that share our solar system. The date honors the anniversary of the Tunguska event of June 30, 1908, when an asteroid or comet fragment exploded over Siberia and flattened roughly 2,000 square kilometers of forest, the largest impact event in recorded history.
The observance was co-founded in 2014 by astrophysicist and Queen guitarist Brian May, filmmaker Grig Richters, Apollo 9 astronaut Rusty Schweickart, and B612 Foundation leader Danica Remy. In December 2016 the UN General Assembly made it an official annual observance, with the goal of raising public awareness about asteroids and the importance of planetary defense.
Events run worldwide: live broadcasts from observatories, panel discussions with astronauts and asteroid scientists, star parties, and school programs. The day's serious message sits beneath the fun. Space agencies including NASA and ESA actively track near-Earth objects and test deflection techniques, work that turns an ancient fear of the sky into modern, measurable risk management.
History of International Asteroid Day
Asteroid Day began in 2014, when Brian May, the Queen guitarist who later completed a doctorate in astrophysics, joined filmmaker Grig Richters, astronaut Rusty Schweickart, and foundation leader Danica Remy to launch a global movement for asteroid awareness. They chose June 30 to commemorate the Tunguska explosion of 1908, an airburst over remote Siberia that knocked down millions of trees across more than 2,000 square kilometers, a stark reminder of what even a modest space rock can do. The campaign released the 100X Declaration, signed by scientists, astronauts, and Nobel laureates, calling for a hundredfold increase in the rate of asteroid discovery. In December 2016 the United Nations General Assembly formally designated June 30 as International Asteroid Day, placing it alongside other official UN observances. Since then the day has been marked with coordinated programs involving the UN Office for Outer Space Affairs, space agencies, museums, and astronomy clubs, turning anniversary remembrance into an annual worldwide science event.
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Frequently Asked Questions
- When is International Asteroid Day?
- International Asteroid Day falls every year on June 30, the anniversary of the 1908 Tunguska event over Siberia.
- Is International Asteroid Day a public holiday?
- No. It is a United Nations observance, not a public holiday, so offices and schools operate normally. It is marked through science events, broadcasts, and educational programs rather than days off.
- How do people celebrate International Asteroid Day?
- People celebrate by watching live space broadcasts, attending planetarium shows and star parties, joining asteroid-tracking citizen science projects, and learning about planetary defense missions like DART.