![]() ![]() These two men had discovered the ancient frozen crystal structure of iron meteorites, unchanged for billions of years. No such pattern is seen in iron mined on Earth. These became known as Widmanstätten lines after Count Alois von Beckh Widmanstätten, who made a similar discovery in 1808. Two years later, a British mineralogist, William Thomson, tried polishing an iron meteorite with nitric acid, revealing a striking crystalline pattern. In 1802, he reported that all three types of meteorites had a high level of nickel, a composition unlike anything seen before in terrestrial rocks. Howard was the first to dissect and subject these extraterrestrial stones to chemical analysis. Geologists and chemists also were making great strides in understanding terrestrial rocks and developing techniques to reveal their structure.Īround the year 1800, the British chemist Edward Charles Howard acquired several suspected meteorites, including examples of each of the three main meteorite types recognized today: stony, iron, and stony-iron. Just two years earlier, the astronomer Giuseppe Piazzi had discovered the asteroid Ceres, clearly showing that there were objects other than planets circling the Sun. Over 3,000 stones were recovered, making the event impossible to ignore. On April 26, 1803, the villagers of L’Aigle, France, saw and heard an amazing fall. Where else could these ordinary-looking rocks have originated?īut at the start of the 19th century, a number of events came together that changed the way people understood and studied these objects. It was widely believed that these stones formed in clouds and, when heavy enough, simply fell to Earth. And in 1492, a stone fell from the sky just outside the city of Ensisheim, France, becoming a marvel in Europe for centuries. In 465 b.c., the Greek poet Pindar saw a meteorite land not far from the hill where he was sitting. One of the earliest potential recorded accounts dates to 1478 b.c., when, according to the Parian Chronicle, a “thunderstone” fell on the island of Crete. Humans have seen rocks falling from the sky for thousands of years. The bits of detritus that found their way to Earth in 1969 marked a milestone in our quest to unlock their mysteries. But by the mid-20th century, there was no doubt that these rocks had a cosmic origin. For most of human history, the origin of these stones was an enigma. Geologists, chemists, and other scientists were better prepared to coax secrets from these otherworldly rocks than at any other time in history. And in September, over 200 pounds (90 kg) of cosmic material fell near the town of Murchison in Victoria, Australia, about 100 miles (160 kilometers) north of Melbourne. In February 1969, a massive meteorite rained a couple of tons of stones on the Mexican town of Allende, not far from the Texas border. In the same year, however, nature also provided several tons of cosmic debris for free. NASA had state-of-the-art clean laboratories and equipment ready to analyze these samples in unbelievable detail. In July 1969, the crew of the Apollo 11 brought back nearly 48 pounds (22 kilograms) of pristine lunar rocks from the most incredible - and expensive - rock-collecting expedition in history.
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