Usually, only meteorites made of metal survive the passage through Earth’s atmosphere sufficiently intact to scoop out a crater. But the object which came down in the Puno region of Peru was a relatively fragile stony meteorite. During the fiery descent through Earth’s atmosphere, these are thought to fragment into smaller pieces which then scatter over a wide area.

Yet pieces of the estimated 1m-wide meteorite are thought to have stayed together during entry, hitting the ground as one.
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Peter Schultz told the conference that the meteorite was travelling at about 24,000km/h (15,000mph) at the moment of impact – much faster than would be expected. “This just isn’t what we expected,” said Professor Schultz, from Brown University in Providence, US. “It was to the point that many thought this was fake. It was completely inconsistent with our understanding of how stony meteorites act.”
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At the velocity it was travelling, fragments could not escape the “shock-wave” barrier which accompanies the meteorite’s passage through the atmosphere. Instead, the fragments may have reconstituted themselves into another shape, which made them more aerodynamic. Consequently, they encountered less friction during their plunge to Earth, holding together until they reached the ground. “Although [the meteorite] is quickly broken up, it is behaving like a solid mass,” Professor Schultz told the conference.