Hail, in and of itself, is not an unusual weather phenomenon. The frozen precipitation occurs inside storm clouds when water droplets are cooled below freezing, yet remain in a liquid state. When the supercooled water encounters something solid, such as a speck of dust or an ice crystal, it sticks to the particle and freezes. Updrafts in the storm keep the hailstone aloft as it aggregates ice, growing until its weight is too heavy for the updraft, at which time it plunges to the Earth.
Some scientists believe that there is a larger, more sinister type of ice-chunk precipitation which can form outside of storms, making even the largest hailstones look puny in comparison. There is a great deal of disagreement in the scientific community regarding the origin of these falling slabs of ice, but it is certain that something is causing massive frozen chunks to occasionally drop from seemingly empty skies. The objects are called megacryometeors.
The term was coined by researcher Jesús Martínez-Frías, a planetary geologist from Madrid, Spain. In the year 2000, he investigated a series of such mystery ice meteors which began with a four-and-a-half pound object that smashed through the windshield of parked car in the city of Tocina. It fell out of a clear, sunny sky in January. Soon there were reports of similar incidents in the surrounding area, which continued at irregular intervals for about a week before they stopped as mysteriously as they had started.
Over the past decade, over fifty such objects have been recorded worldwide. Some have been as small as about one pound, but one monstrous mass of ice that fell in Brazil weighed about 400 pounds– almost a quarter of a ton– and crashed through the roof of a Mercedes-Benz factory. One recently made headlines in Oakland, California, weighing over 200 pounds and creating a dent in the Earth three feet deep. A similar event occurred in Chicago last February, crashing through the roof of a house.
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