Meteor air burst

A meteor air burst is an air burst caused by a meteoroid exploding within a planetary body's atmosphere after entering, before actually colliding with the planetary surface (lithosphere or hydrosphere). It is a type of impact event that generates a measurable shock wave but does not leave behind a typical crater or structure in the crust.

Aerodynamic heating causes meteoroids to become so-called fireballs or bolides, with the brightest air bursts known as superbolides. Such meteoroids were originally asteroids and comets of a few to several tens of meters in diameter, which separates them from the much smaller and far more common "shooting stars" that usually burn up quickly upon atmospheric entry. Extremely bright fireballs traveling across the sky are often witnessed from a distance, such as the 1947 Sikhote-Alin meteor and the 2013 Chelyabinsk meteor. If the bolide is large and dense enough, it may survive long enough into the atmospheric entry to build up a spectacular mid-air explosion (i.e. air burst), or to impact the planetary surface as a meteorite and leave behind a distinct impact crater.

Prior to the 20th century, only a very small number of meteor air bursts was ever detected, and even fewer documented. The most powerful known meteor air burst in the modern era was the 1908 Tunguska event, during which a rocky meteoroid about 50–60 m (160–200 ft) in size exploded at an altitude of 5–10 km (16,000–33,000 ft) over a sparsely populated forest in the Podkamennaya Tunguska region of Central Siberia. The resulting shock wave flattened an estimated 30 million trees over a 2,150 km2 (830 sq mi) area, and may have killed 3 people. Modern developments in infrasound detection by the Comprehensive Nuclear-Test-Ban Treaty Organization and infrared Defense Support Program satellite technology have increased the likelihood of detecting meteor air bursts.