Mon Oct 08 14:34:50 CEST 2018

The world has another meteorite “with pedigree,” i.e. a meteorite with known pre-impact trajectory in the Solar System. It has been unofficially called Renchen because four fragments of this object were found near Renchen, Germany, thanks to Czech calculations. The scenario of this meteorite’s fall, leading to findings of the fragments, was determined by the scientists of the Interplanetary Matter Department of the Astronomical Institute of the CAS through the analysis of data recorded by instruments in Czech, German, and French part of the European Fireball Network, a long-term international experiment started more than half a century ago by Doctor Zdeněk Ceplecha.

On Tuesday, July 10th, half an hour before midnight local time, a very bright meteor, or a bolide, shone over a large area around the middle part of the Rhine River. Except in some parts of France and Germany, observation of this bolide was complicated by extensive cloud cover. The bolide’s fall was extremely steep and short, the whole phenomenon lasting only four seconds, and the bolide – shining brighter than a full moon – therefore attracted only a limited attention. Fortunately, it was recorded by instruments from the Czech and German parts of the European Fireball Network where the sky was at least partially clear, and thanks to these records the bolide could be described with adequate accuracy and reliability. At the same time, it was predicted the atmospheric entry resulted in the fall of meteorites, and location and size of the fragments was determined.

A part of a sky-wide photo of the bolide from July 10, 2018, taken by an automated
digital bolide camera on the station of the Czech Hydrometeorological Institute at Přimda.
Bolid is very low over the western horizon (photo: Astronomical Institute of the CAS)


Fragments ranging from several grams to one kilogram

After the team of the Interplanetary Matter Department in Ondřejov evaluated the data, their German colleagues were actually able to find the meteorites in the predicted area (among the smallest was a meteorite weighing only 4.8 g found on September 30; among the largest was a fragment weighing 955 g found on July 31).

This is without doubt one of the greatest successes of the European Fireball Network, established in 1963 by Doctor Zdeněk Ceplecha. Currently, there are only about 30 meteorites “with pedigree,” i.e. meteorites whose trajectory was determined thanks to direct observation through instruments. In more than half of these cases (including the very first one, meteorite Příbram from April 7, 1959), the scientists from the Astronomical Institute of the CAS were involved in the calculations. Thanks to their efforts, other meteorites have been recently found, as well: Žďár nad Sázavou (December 9, 2014), Hradec Králové (May 17, 2016), or Stubenberg, Germany (March 6, 2016).

The first meteorite Renchen (M1), weighing 11.9 g in the position where it was found
two weeks after the bolide’s fall (foto: Ralph Sporn a Martin Neuhofer, Pavel Spurný)


Detailed report (in Czech) with more images can be found here: http://www.asu.cas.cz/articles/1414/19/dalsi-meteorit-s-rodokmenem-nalezeny-na-zaklade-dat-porizenych-evropskou-bolidovou-siti


Prepared by: Department of Media Communication of the Head Office of the CAS, based on a press release by the Astronomical Institute of the CAS
Main photo: The second as well as the largest meteorite Renchen (M2), weighing 955 g, found on July 31, 2018 (photo: Ralph Sporn and Martin Neuhofer)