Airburst
An airburst is when an incoming space rock explodes in the atmosphere instead of hitting the ground in one piece.
As a large meteoroid or small asteroid dives deeper, the air in front of it presses harder and harder. When that pressure becomes greater than the rock's strength, it shatters. The pieces slow down abruptly and dump their energy into the air in an instant, releasing a blast like an explosion. This is an airburst.
The most famous example is the Tunguska event in Siberia on 30 June 1908. An object probably tens of metres across exploded several kilometres above the forest and flattened roughly 2,000 square kilometres of trees, yet no crater and no confirmed meteorite has ever been found. In 2013 the Chelyabinsk airburst over Russia was much smaller but still shattered windows across a city. Scientists study airbursts because they are the most likely kind of dangerous impact in a human lifetime.
The signs of an airburst are a dazzling flash, a long smoke trail, and a powerful pressure wave that arrives later, followed by booms. Afterwards, trees or buildings may show damage pointing away from the spot beneath the explosion.
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Level: Explorer Ages 10 and up