As the world celebrates Asteroid Day for the anniversary of the Tunguska Event, a cosmological researcher warned that the chances of a massive space rock colliding with Earth are actually higher than most people think.

The Tunguska event, which took place over Russia’s Podkamennaya Tunguska River on June 30, 1908 is regarded as a grim reminder of just how destructive an asteroid impact could be.

According to Randall Carson, founder of the Cosmographic Research Institute, the asteroid that hit Russia 111 years ago was about 150 feet long and its mid-air explosion produced an energy that’s equivalent to a 15-megaton hydrogen bomb.

Luckily, the explosion that levelled 770 square miles of forest didn’t cause human casualties since it happened over a remote area.

During a live interview with RT, Carlson warned that the chances of a similar impact event happening is higher than what most people believe. In addition, since the world’s population is bigger now compared to what it was a century ago, Carlson believes that a similar catastrophic event would cause the deaths of millions.

“The odds are higher than most people think,” he told RT. “For anybody that is paying attention to this sort of thing, there is regularly near misses. Last month there was one.”

“Pretty much on a monthly basis, there will be some of this cosmic debris that is flying by in the nearby cosmic neighborhood,” he added.

Carlson pointed out that Earth gets hit by tiny asteroids on a daily basis. Since these are very small, many of them burn up and disintegrate as they enter the upper layer of Earth’s atmosphere. However, once in a while, an asteroid big enough to get through the atmosphere hits Earth. Carlson said that even though these objects are smaller than the one that caused the Tunguska Event, they can still cause significant damage.