Meteor air burst

Meteoroids enter the Earth's atmosphere from outer space traveling at speeds of at least and often much faster. Despite moving through the rarified upper reaches of Earth's atmosphere the immense speed at which a meteor travels rapidly compresses the air in its path. The meteoroid then experiences what is known as ram pressure. As the air in front of the meteoroid is compressed its temperature quickly rises. This is not due to friction, rather it is an adiabatic process, a consequence of many molecules and atoms being forced to occupy a smaller space. Ram pressure and the very high temperatures it causes are the reasons few meteoroids make it all the way to the ground. Most simply burn up or are ablated into tiny fragments. Larger or more solid meteorites may explode instead. Airburst explosions The use of the term explosion is somewhat loose in this context, and can be confusing. This confusion is exacerbated by the tendency for airburst energies to be expressed in terms of nuclear weapon yields, as when the Tunguska airburst is given a rating in megatons of TNT. Large meteoroids do not explode in the sense of chemical or nuclear explosives. Rather, at a critical moment in its atmospheric entry the enormous ram pressure experienced by the leading face of the meteoroid converts the body's immense momentum into a force blowing it apart over a nearly instantaneous span of time. That is, the mass of the meteoroid suddenly ceases to move at orbital speeds when it breaks up. Conservation of energy implies much of this orbital velocity is converted into heat. In essence, the meteoroid is ripped apart by its own speed. This occurs when fine tendrils of superheated air force their way into cracks and faults in the leading face's surface. Once this high pressure plasma gains entry to the meteoroid's interior it exerts tremendous force on the body's internal structure. This occurs because the superheated air now exerts its pressure over a much larger surface area, as when the wind suddenly fills a sail. This sudden rise in the force exerted on the meteoroid overwhelms the body's structural integrity and it begins to break up. The breakup of the meteoroid yields an even larger total surface area for the superheated air to act upon and a cycle of amplification rapidly occurs. This is the explosion, and it causes the meteoroid to disintegrate with hypersonic velocity, a speed comparable to that of explosive detonation. recommended that "Because recent studies of meteor airbursts have suggested that near-Earth objects as small as 30 to 50 meters in diameter could be highly destructive, surveys should attempt to detect as many 30- to 50-meter-diameter objects as possible." == Frequency ==

The table from Earth Impact Effects Program (EIEP) estimates the average frequency of airbursts and their energy yield in kilotons (kt) or megatons (Mt) of TNT equivalent. events (1994–2013) == Events ==

Before the 20th century While airbursts undoubtedly happened prior to the 20th century, reliable reports of such are sparse. A possible example is the Qingyang event of 1490, which had an unknown energy yield but was reportedly powerful enough to cause 10,000 deaths. Modern researchers are sceptical about the figure, but had the Tunguska event occurred over a highly populous district, it might have caused a similar level of destruction. After 1900 Depending on the energy estimates, there were only 3–4 known airbursts in the years 1900-1999 with energy yield greater than 80 kilotons (in 1908, 1930?, 1932?, and 1963), slightly greater than the estimate of 3.8 in the EIEP table since airbursts over uninhabited land and ocean were not monitored before mid-century. However, the 1963 event may have not been a meteor but instead a nuclear test. Most values for the 1930 Curuçá River event put it well below 1 megaton, comparable to the Chelyabinsk meteor and Kamchatka superbolide. The Comprehensive Nuclear-Test-Ban Treaty Organization and modern technology have improved multiple detection of airbursts with energy yield 1–2 kilotons every year within the last decade. The first airburst of the 21st century with yield greater than 100 kilotons came from the 2013 Chelyabinsk meteor, which had an estimated diameter of 20 metres. Note: For sorting purposes, location is given in "general:specific" format. For example, "Europe: Spain". This table contains a chronological list of events with a large yield at least 3 kilotons since 2005, with earlier or smaller events included if widely covered in the media. Airbursts per year As of January 2026, the number of airbursts each year since 2005, as reported in the JPL Fireball and Bolide Reports are: On average 32.2 airbursts are recorded each year, with an average energy of 1.27kt per event, 40.5kt per year, and an estimated total of 950.2kt of energy since 2005. Of note is that when excluding Chelyabinsk, that number falls to 0.68kt per event, 24.2kt per year, and 509.2kt of total energy. Chelyabinsk thus constitutes 46.3% of all airburst energy since 2005. == See also ==