![]() ![]() ![]() A freshly fallen meteorite is more likely to acquire a coating of frost than to start a fire. The meteorite is ice-cold in space, and most of its interior remains cold even after its brief fiery plunge through the atmosphere. Such stories have always proved to be wrong. Every few months news outlets report that a meteorite has been implicated in the start of a fire. Most observers of a bright fireball conclude that part of it hit the ground, but that is rarely the case. There are, however, many false alarms about meteorite falls. The 2013 Chelyabinsk fireball, which we discussed in the chapter on Comets and Asteroids: Debris of the Solar System, produced tens of thousands of small meteorites, many of them easy to find because these dark stones fell on snow. (A few meteorites have even hit buildings or, very rarely, people see Making Connections: Some Striking Meteorites). Observed meteorite falls, in other words, may lead to the recovery of fallen meteorites. If we search the area beneath the point where the fireball burned out, we may find one or more remnants that reached the ground. First, sometimes bright meteors (fireballs) are observed to penetrate the atmosphere to low altitudes. Whatever the ultimate source of the meteorites, they do not appear to come from the comets or their associated particle streams. No meteorites have ever been recovered in association with meteor showers. It is important to remember that such a shower of meteorites has nothing to do with a meteor shower. Such a fall occurs when a single larger object breaks up during its violent passage through the atmosphere. Meteorites sometimes fall in groups or showers. The idea that indeed “stones fall from the sky” was generally accepted only after a scientific team led by French physicist Jean-Baptiste Biot investigated a well-observed fall in 1803. The modern scientific history of the meteorites begins in the late eighteenth century, when a few scientists suggested that some strange-looking stones had such peculiar composition and structure that they were probably not of terrestrial origin. At least one sacred meteorite has apparently survived in the form of the Ka’aba, the holy black stone in Mecca that is revered by Islam as a relic from the time of the Patriarchs-although understandably, no chip from this sacred stone has been subject to detailed chemical analysis. A number of religious texts speak of stones from heaven, which sometimes arrived at opportune moments to smite the enemies of the authors of those texts. The falls of the earliest recovered meteorites are lost in the fog of mythology. Before that, these strange stones were either ignored or considered to have a supernatural origin. Occasional meteorites have been found throughout history, but their extraterrestrial origin was not accepted by scientists until the beginning of the nineteenth century. These rocks from the sky carry a remarkable record of the formation and early history of the solar system. Some meteorites are loners, but many are fragments from the breakup in the atmosphere of a single larger object. Meteorites fall only very rarely in any one locality, but over the entire Earth thousands fall each year. Explain how the study of meteorites informs our understanding of the age of the solar system.Īny fragment of interplanetary debris that survives its fiery plunge through Earth’s atmosphere is called a meteorite.Explain how primitive stone meteorites are significantly different from other types.Describe how most meteorites have been found. ![]() Explain the origin of meteorites and the difference between a meteor and a meteorite.By the end of this section, you will be able to: ![]()
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