PROGES S
ASTRONOMY A t 22:27 on 7 November 2020, the sky above large parts of eastern Svealand was illuminated for around three seconds. In western Uppland, the light was followed by a thunder-like bang and a long rumbling sound. Many people wondered what was happening. After fragments had been found and examined, researchers from Uppsala University and the Swedish Museum of Natural
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History, aided by Norwegian colleagues, were soon able to ascertain that a large meteor – or bolide – had fallen to earth. This was the first Swedish find of an observed meteorite for over 66 years and the first observed iron meteorite fall in Sweden. “Meteorites fall towards the Earth at very high speeds – several tens of kilometres per second. Once a rock meets the Earth’s atmosphere, it decelerates and the air around it begins
to glow, hence the light phenomenon,” explains Eric Stempels, a researcher at the Department of Physics and Astronomy. The resulting heat melts the surface and the meteor will usually burn up completely. If the rock is large enough, fragments may survive the violent journey through the atmosphere. The remnants can then be found on the ground in the form of meteorites.
PHOTO: NORDISKA RIKSMUSEET
Large bolide falls from the sky
A few small dark fragments of meteorite crust have been found, about 3 mm in size.
