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What gives meteorites their shape?

Meteoroids coming from outer space are randomly shaped, but many of these, which land on earth as meteorites, are found to be carved into cones. Scientists have now figured out how the physics of flight in the atmosphere leads to this transformation. The progression involves melting and erosion during flight that ultimately results in an ideal shape as meteoroids hurl through the atmosphere. The forces behind the peculiar shapes of meteorites, which are meteors or "shooting stars" that survive the fiery flight through the atmosphere and land on Earth, have long been a mystery. To explore the forces that produce cone-shaped meteorites, the researchers, replicated meteoroids traveling through outer space: clay objects, attached to a rod, served as "mock meteorites" that erode while moving through water. The clay objects held in the water current were eventually carved into cones of the same angularity as conical meteorites -- not too slender and not too broad. However, the researchers recognized the limitations of this experimental design: unlike the clay objects, actual flying meteoroids are not held in a fixed position and can freely rotate, tumble, and spin. This distinction raised the following question: what allows meteorites to keep a fixed orientation and successfully reach Earth?

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