Free Astronomy Magazine November-December 2016

SMALL BODIES into oblivion, probably because it was covered by soil layers transported by natural phenomena. The interest in Campo del Cielo has been successively revived over the twentieth century, and in 1969 a few researchers spotted at a depth of about 5 meters a massive metallic bulk, al- most certainly an enormous fragment of the meteorite that had fallen 4 mil- lennia earlier. Unfortunately, because of organizational and mostly financial problems, it was only possible to pro- ceed with the object recovery in 1980. The meteorite that came out of the buried crater immediately appeared enormous and, in fact, its approximat- ed weight, 37 tons, put it in second place compared to the meteorites found on our planet, overcome only by the gigantic meteorite Hoba, retrieved in Namibia in 1920 and whose weight is estimated to be approximately 60 tons (actually, it was never extracted from the ground). From the moment it was dug up in the province of Chaco, the “new” me- teorite came to be called El Chaco. This last extraction marked a turning point in the in- vestigation of Campo del Cielo, accelerat- ing the identification of new buried craters and, then, of other big fragments of the original meteoroid. In relatively recent times, the most interesting extractions have resulted from the collaboration between the local Asociación Chaqueña de Astrono- mía and the great expert and meteorite hunter William A. Cassidy, former Geology and Planetary Science professor, already a leading figure on the identification of El Chaco. Thanks to NASA’s financing, be- tween 2005 and 2008 the researchers were able to study the meteorite shower disper- sion using images taken by airplanes and satellites, and through topo- graphic and magnetic maps they managed to identify un- known impact craters, due to them being cov- ered with soil and vegetation layers. The result was the extraction of several me- teorites of var- ious tons, such as La Sorpresa, El Santiagueño, T wo more multi-ton me- teorites discov- ered by the Aso- ciación Chaqueña de Astronomía: Carmen Sosa (5.68 t) and, be- low, La Sorpresa (14.87 t). [Insti- tuto Turismo Chaco]