fireball
A fireball (bolide) is an unusually bright meteor that glows because a fragment of an asteroid or comet heats up as it enters Earth's atmosphere. It often prompts UFO reports because it is spectacular and fast.
A fireball (also called a bolide) is an unusually bright meteor: a piece of rock or metal entering Earth's atmosphere at high speed glows hot due to friction and the compression of the atmosphere, and draws a long, spectacular streak of light across the sky. By the astronomical definition, a fireball is a meteor that exceeds even the maximum brightness of Venus.
Characteristics
The phenomenon usually lasts a few seconds. The color of a fireball can vary (white, yellow, green, bluish or reddish hues also occur), and it often breaks apart into pieces, leaving smaller sparks behind. It may explode in the atmosphere, in which case it can also be accompanied by a thunder-like sound or a shock wave. If part of the material reaches the ground, it is called a meteorite.
Fireballs can be observed anywhere in the world, but most of them go unnoticed because they occur over the ocean or over uninhabited areas, or during the day.
Connection to UFO reports
According to both the official finding and skeptical researchers, fireballs provide one of the most common natural explanations for sky phenomena reported as unidentified flying objects. A suddenly appearing, fast, bright and sometimes colorful object that disappears or breaks into pieces is easy to misinterpret. Witnesses also often report that the phenomenon seemed close, although it actually took place at altitudes of tens or hundreds of kilometers.
Some UFO believers hold that not every such report can be explained by meteors, but for most known events the astronomical data (for example, recordings made from multiple locations, trajectory calculations) point to a natural origin.
Today, the observation of fireballs is also aided by camera networks and satellite sensors, which makes it easier to identify such phenomena.
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