International Asteroid Day: History, Key Facts, Activities

~4 min

The 8th annual Asteroid Day will be held on June 30. By observing it, you can help save the Earth from a serious threat, so it’s very important. We've arranged a big sale for the occasion – don’t miss a special offer!


To expand your knowledge about asteroids, you can also take our asteroids quiz.

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What is Asteroid Day?

Asteroid Day is a global information campaign aimed to educate people about the risks of asteroid impacts. The United Nations officially sanctioned it in 2016. Asteroid Day events are hosted around the Earth by thousands of independent Asteroid Day Event Organizers.

When is Asteroid Day?

Asteroid Day is held annually on June 30. This date is dedicated to the most harmful asteroid-related event in the Earth’s recent history — the Siberian Tunguska event.

Who founded Asteroid Day?

The idea was initiated by:

  • Brian May, an astrophysicist, and musician (lead guitarist of the rock band Queen);
  • Grigorij Richters, a filmmaker who wrote and directed 51 Degrees North, the science fiction film about asteroids falling on the Earth;
  • Danica Remy, President and chief executive of B612 Foundation, whose mission is to protect the Earth from asteroid impacts;
  • Russel L. Schweickart, a research scientist, NASA astronaut, and B612’s co-founder.

In 2014, they announced the first Asteroid Day and gained wide support: more than 200 scientists, astronauts, and artists co-signed the Asteroid Day Declaration. In 2016, the United Nations declared it an international observance.

How to participate in Asteroid Day?

Asteroid Day events are held worldwide. You can find the offline and online events for your location using the map on the Asteroid Day website. Better check the website in advance: although it’s recommended to arrange an event on June 30, event organizers can pick another date close to it.

If you prefer to stay home, on any day from June 1 to July 4, you can watch Asteroid Day TV. It features such broadcasts as “The Case for Mapping the Asteroids” or “TED All About Asteroids Hour”. Asteroid Day LIVE — the main broadcast with asteroid content and commentary from astronauts, experts, and celebrities — goes live on June 30, from 9:00 to 14:00 GMT.

One more way to participate is to sign the Asteroid Day declaration, officially named the 100X Declaration. It calls for increasing the asteroid discovery rate by 100,000 (or 100x) per year within the next ten years.

The Asteroid Day founders made such a declaration because the current rate of discovered asteroids with a potential to impact the Earth is too low. More than one million asteroids can possibly hit our planet; however, we have detected only about one percent of them. The declaration appeals to scientists mainly, but everyone can take part and sign it.

Each Asteroid Day is a noteworthy event for those concerned about asteroid impacts and science and space lovers in general. We've also decided to take part in the event. Upon your requests, we’ll re-open Lifetime Access to the Sky Tonight app with a discount of up to 70%! But the offer is time-limited: you can get it only from June 27 to June 30. After that, only Premium Access will be available. Don’t miss your chance!

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What would happen if an asteroid hit the Earth? Our infographic shows that the destruction scale depends on an asteroid's size. Small asteroids can go unnoticed, while larger ones can wipe out a city or an entire population of the Earth. We'll describe the results of the largest asteroid impacts in the Earth's history.

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Tunguska: flattened 80 mln trees

The Siberian Tunguska event was the massive explosion that took place on June 30, 1908, near the Podkamennaya Tunguska River in central Siberia, Russia. Presumably, this explosion was caused by an asteroid around 50-100 meters in diameter. The energy of this explosion is estimated to be a thousand times more powerful than the atomic bomb dropped on Hiroshima, Japan.

Chelyabinsk: exploded over residential areas

On February 15, 2013, an asteroid around 20 meters in diameter entered the Earth’s atmosphere and blew apart in the sky above Chelyabinsk city, Russia. It is estimated that the energy of the explosion was 20-30 times higher than the energy of the Hiroshima atomic bomb. The airwave busted out the windows and knocked down parts of buildings in six nearby cities. About 1,500 people were injured, mostly by the shattered glass; fortunately, no lethal outcomes were reported. The event went viral on social media and provoked a new round of studying a potential asteroid threat.

Chicxulub: took away dinosaurs

How did dinosaurs go extinct? The most popular theory is that 66 million years ago, the Earth collided with a giant asteroid (about 10 kilometers in diameter), which left the Chicxulub impact crater (about 180 kilometers in diameter and 20 kilometers in depth) in Mexico. The shock wave provoked earthquakes, tsunamis, winds exceeding 1000 km/h, and clouds of gasses and dust blocking the Sun. Many dinosaurs died from the explosive force, and the others followed later. Vegetation was severely damaged; from a lack of nutrition, large herbivores died, then carnivores that fed on them.

How to stop an asteroid from hitting the Earth?

Humanity is working on possible ways to do it. Earlier, we told you about NASA’s DART mission. Other solutions are also proposed, such as the slow gravity tractor, the use of solar or nuclear energy, and even spray paint. The thing is, we can’t unfold them five minutes before the collision. They all need several years of development, tests, and further deployment. The sooner we detect a dangerous asteroid, the more chances we will have to save the Earth. That’s why it is vital to observe Asteroid Day, raise awareness about asteroid impact hazards, and encourage research.

Wishing you non-asteroids skies and happy observations!