Small Worlds With Lava Oceans Might Have Given Us Meteorites

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https://www.nytimes.com/2020/06/22/science/meteorites-chondrites-chondrules.html

Source: By Jonathan O’Callaghan, The New York Times. 

Excerpt: Researchers propose a new model to explain the formation of most of the meteorites that make it to Earth. “Droplets of fiery rain.” That’s how Henry Clifton Sorby, a 19th-century British mineralogist, described the tiny spheres called chondrules found within meteorites. Chondrules are such dominant features of these meteorites that they are called chondrites, and they account for 86 percent of meteorites that have been found on Earth. Their origin, however, remains a mystery. ...Now some scientists think they have a new answer to this rocky enigma: The chondrites may have formed in an unusual event during a narrow window of time in the early solar system. The findings [https://www.sciencedirect.com/science/article/abs/pii/S0019103517302476], presented at a virtual meeting of the American Astronomical Society this month by William Herbst and James Greenwood of Wesleyan University in Connecticut, paint a strange picture of what parts of the solar system were like before the planets we know began to form. ...Their results suggest a crowded landscape in the early inner solar system, with a nascent sun surrounded by thousands of planetesimals, the rocky building blocks of planets, each tens of miles or so in size. On some of their surfaces were oceans of lava that reached temperatures of more than 3,000 degrees Fahrenheit. When even smaller rocky bodies — asteroids — got close to these young worlds, they would have been briefly heated by this lava. That rapidly melted portions of these objects, which then passed by and cooled to form chondrules....   

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