Bolide

The term bolide (from the Greek βολις, bolis, missile) can refer to either an extraterrestrial body that collides with the Earth, or to an exceptionally bright, fireball-like meteor regardless of whether it ultimately impacts the surface.

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The object itself is a meteoroid; the streak of light is a meteor (or shooting star). If the meteor is brilliant enough to cast shadows, it is a fireball. Finally, if the object appears to explode, it is called a detonating fireball or bolide; an alternate definition holds that it is a bolide if sound can be heard coming from its passage.

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When used in the first sense, the bolide may explode either on impact with the Earth's surface or at a low altitude above it, creating a large impact crater. It is a generic term that does not imply the nature of the impacting body, i.e., whether it is a rocky or metallic meteorite, asteroid, icy comet, etc. Some scientists suggest that a glancing collision with a planet about the mass of Mars, ca. 4.5 billion years ago, may have formed the Moon.

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Since the Chicxulub bolide has been suggested as the cause of the extinction event that exterminated the dinosaurs 65 million years ago, bolides are frequently suggested as causes of major climate changes and mass extinctions. However, no further bolide-induced extinction events have yet been securely identified. Compare Tollmann's hypothetical bolide for an example of bolide speculations in currently popular alternative geology.

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Noteworthy bolide impacts include:

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• Chicxulub Crater off the coast of Yucatan
• Sudbury Basin in Ontario, Canada.
• Barringer crater in Arizona, also known as 'Meteor Crater'
• Tunguska event in Siberia 1908
• Chesapeake Bay impact crater
• Vitim event in Siberia 2002
• Silverpit crater in the North Sea
Bolide: See also ►



 

Greek: The noun Greek refers to:...

Meteor: A meteor is the visible path of a meteoroid that enters the Earth's (or another body's) atmosphere, commonly called a shooting star or falling star. The visibility is due to the heat produced by the ram pressure (not friction, as is commonly assumed) of atmospheric entry. A very bright meteor, brigh...

Meteoroid: A meteoroid is a relatively small (sand- to boulder-sized) fragment of debris in the Solar System. When entering a planet's atmosphere, the meteoroid heats up and partially or completely vaporizes. The gas along the path of the meteoroid becomes ionized and glows. The trail of glowing vapor is calle...