Every year on June 30, the world marks World Asteroid Day to spread awareness about the dangers posed by near-Earth objects (NEOs), particularly asteroids. The United Nations General Assembly officially designated this day in December 2016, not only to commemorate a catastrophic event in Earth’s recent history but also to promote global preparedness in the face of future asteroid threats.
Remembering the Tunguska Event: Nature’s Wake-Up Call
- World Asteroid Day coincides with the anniversary of the Tunguska event, which occurred on June 30, 1908, over Siberia, Russia.
- A massive asteroid, estimated to be between 50–60 meters in size, exploded in the atmosphere with a force 185 times more powerful than the Hiroshima bomb, flattening 2,000 square kilometres of forest.
- Despite the magnitude of the event, its remote location meant it went largely unnoticed globally at the time.
- The first scientific investigation arrived only in 1927, 19 years later.
- That expedition found clear evidence of destruction from a shockwave and heat blast, making it the most powerful asteroid impact in recorded history.
What Is World Asteroid Day?
- In 2016, the United Nations General Assembly declared June 30 as International Asteroid Day, following a proposal from astronauts with the Association of Space Explorers.
- The aim is to raise global awareness about asteroid threats and encourage investment in detection, tracking, and planetary defense.
UN Resolution and Global Cooperation
- In December 2016, the UN General Assembly adopted Resolution A/RES/71/90, officially declaring June 30 as International Asteroid Day.
- This followed a proposal by the Association of Space Explorers, supported by the Committee on the Peaceful Uses of Outer Space (COPUOS).
- The goal is to foster global cooperation in asteroid detection, monitoring, and deflection strategies, emphasizing the need for better planetary defense infrastructure.
The First Asteroid Ever Discovered
- Back in 1801, Italian astronomer Giuseppe Piazzi discovered Ceres, the first known asteroid.
- Originally mistaken for a planet, Ceres remains the largest object in the asteroid belt between Mars and Jupiter.
Other Major Asteroid Events in History
Asteroids have made their mark on Earth in powerful ways,
- Chelyabinsk, Russia (2013): A fireball exploded mid-air, injuring over 1,600 people due to shattered glass.
- Chicxulub Impact (66 million years ago): The asteroid that wiped out the dinosaurs and altered Earth’s climate.
- Meteor Crater, Arizona (50,000 years ago): Left a 1.2 km-wide crater, still visible today.
- 2008 TC3 (Sudan, 2008): The first asteroid detected before impact, which exploded in the sky and dropped fragments in the desert.
- Sulawesi, Indonesia (2009): A space rock exploded in the sky with the force of 50,000 tons of TNT.
Why Should We Care About Asteroids?
- Asteroids are more than threats—they’re time capsules from the early solar system.
- They hold clues to how planets formed, how life may have started, and what Earth was like billions of years ago.
- But they also remind us of space hazards. Some Near-Earth Objects (NEOs) cross Earth’s orbit.
- While most pose no danger, a few could cause real damage if not tracked.
NASA’s DART Mission: A Milestone in Planetary Defence
- In 2022, NASA launched DART (Double Asteroid Redirection Test), a mission that intentionally crashed into an asteroid to change its path.
And it worked. - This historic success proved that asteroid deflection is possible—paving the way for future Earth-protection strategies.
Looking Ahead: 2029 Declared the International Year of Asteroid Awareness
- In a visionary move, the UN has declared 2029 as the International Year of Asteroid Awareness and Planetary Defence.
- This coincides with the close approach of asteroid 99942 Apophis, which will safely pass Earth on April 13, 2029, at just 32,000 kilometers away—closer than some satellites.
- Apophis, measuring around 340 meters, will be visible to the naked eye in parts of Europe, Africa, and Western Asia, offering an unparalleled chance for scientists and the public to observe an asteroid flyby.