Manuel Moreno-Ibáñez1, Elizabeth A. Silber2, Maria Gritsevich3,4, and Josep M. Trigo-Rodríguez1,5
The Astrophysical Journal 863, 174 Link to Article [https://doi.org/10.3847/1538-4357/aad334]
1Institute of Space Sciences (ICE, CSIC), Meteorites, Minor Bodies and Planetary Science Group, Campus UAB, Carrer de Can Magrans, s/n E-08193 Cerdanyola del Vallés, Barcelona, Catalonia, Spain
2Department of Earth, Environmental and Planetary Sciences, Brown University, Providence, RI 02912, USA
3Department of Physics, University of Helsinki, Gustaf Hällströmin katu 2a, P.O. Box 64, FI-00014 Helsinki, Finland
4Institute of Physics and Technology, Ural Federal University, Mira str. 19. 620002 Ekaterinburg, Russia
5Institut d’Estudis Espacials de Catalunya (IEEC), C/ Gran Capitá, 2-4, Ed. Nexus, desp. 201, E-08034 Barcelona, Catalonia, Spain
Infrasound monitoring has proved to be effective in detection of meteor-generated shock waves. When combined with optical observations of meteors, this technique is also reliable for detecting centimeter-sized meteoroids that usually ablate at high altitudes, thus offering relevant clues that open the exploration of the meteoroid flight regimes. Since a shock wave is formed as a result of a passage of the meteoroid through the atmosphere, the knowledge of the physical parameters of the surrounding gas around the meteoroid surface can be used to determine the meteor flow regime. This study analyzes the flow regimes of a data set of 24 centimeter-sized meteoroids for which well-constrained infrasound and photometric information is available. This is the first time that the flow regimes for meteoroids in this size range are validated from observations. From our approach, the Knudsen and Reynolds numbers are calculated, and two different flow regime evaluation approaches are compared in order to validate the theoretical formulation. The results demonstrate that a combination of fluid dynamic dimensionless parameters is needed to allow a better inclusion of the local physical processes of the phenomena.