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TitleMeteorite strikes Peru
AuthorJackson, L E, Jr.; Brown, P; Melosh, J; Hill, D
SourceGeotimes July, 2008 p. 6-11
Alt SeriesEarth Sciences Sector, Contribution Series 20080255
Mediapaper; on-line; digital
AreaCarancas; Peru
Lat/Long WENS-73.0000 -67.0000 -15.0000 -17.0000
Subjectsextraterrestrial geology; meteorite craters; meteorites; craters
The meteoroid impact at Carancas was a surprising event for scientists who study meteorites and impact craters. It is not clear how a chondrite, a relatively weak rock, was able to survive passage through the earth's atmosphere intact and impact at least four times the speed of sound, but it did! One element may lie in the high elevation of the Altiplano - Labout 4 km above sea level. Had the impact occurred closer to the sea level where the atmosphere was much denser, the velocity of the impact would have been slower and the crater considerably smaller. It is worth noting that the Sikhote-Alin shower is believed to have resulted from breakup of the original object at very low altitude (~5 km) so it is conceivable that the Carancas impactor might have fragmented in the last few seconds of its flight if it had descended to sea level. Although destructive on the scale of a city block, meteoroids on the scale of Carancas often fly under the radar screens of astronomers who search the skies for potentially hazardous objects. For example, the Catalina Sky Survey at the University of Arizona Lunar and Planetary Laboratory can detect small near Earth objects that they refer to as ‘flying couches'. However, the world's asteroid surveys can't cover the whole sky every night. So the goal is to locate the much larger Potentially Hazardous Asteroids (PHAs) long before they threaten Earth. PHAs have the power to destroy whole cities, create tsunamis or even threaten civilization at the larger end of their scale. We can all be thankful that our atmosphere is always on guard to largely shield us from weekly cratering by 'flying couches' from space-- the Carancas fireball being a rare exception.

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