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A meteor air burst is a type of air burst in which a meteoroid explodes after entering a planetary body's atmosphere. This fate leads them to be called fireballs or bolides , with the brightest air bursts known as superbolides .
In physics, a shock wave (also spelled shockwave), or shock, is a type of propagating disturbance that moves faster than the local speed of sound in the medium. Like an ordinary wave, a shock wave carries energy and can propagate through a medium, but is characterized by an abrupt, nearly discontinuous, change in pressure , temperature , and ...
Shock waves are common in astrophysical environments. [1]Because of the low ambient density, most astronomical shocks are collisionless.This means that the shocks are not formed by two-body Coulomb collisions, since the mean free path for these collisions is too large, often exceeding the size of the system.
A meteor, known colloquially as a shooting star or falling star, is the visible passage of a glowing meteoroid, micrometeoroid, ...
The defining criterion of a shock wave is that the bulk velocity of the plasma drops from "supersonic" to "subsonic", where the speed of sound c s is defined by = / where is the ratio of specific heats, is the pressure, and is the density of the plasma.
The bright flash of the shockwave, or as astronomers call it the "shock breakout," pushes outward as the distant body turns from star to supernova.
In contrast, Brad Sturtevant, a leading researcher in shock wave physics at Caltech for many decades, found that shock waves can result from handgun bullet impacts in tissue. [27] Other sources indicate that ballistic impacts can create shock waves in tissue. [21] [28] [29] Blast and ballistic pressure waves have physical similarities.
Also actiniform. Describing a collection of low-lying, radially structured clouds with distinct shapes (resembling leaves or wheels in satellite imagery), and typically organized in extensive mesoscale fields over marine environments. They are closely related to and sometimes considered a variant of stratocumulus clouds. actinometer A scientific instrument used to measure the heating power of ...