Statistical and probabilistic analysis of meteor and superbolide observations from ground and space platforms

ABSTRACT This study analyses the positional and physical data of meteors and superbolides observed by the ground-based Brazilian Meteor Observation Network (BRAMON) and the US government’s space-based sensors and Geostationary Operational Environmental Satellite (GOES) to identify biases in the data bases and parameters that distinguish these populations. The spatial distribution of superbolides from the Center for Near-Earth Object Studies (CNEOS) data base with impact energy ≥1 kt was found to be uniform, with a global frequency estimate of $5.73 \times 10^{-9}$ events km−2 yr−1. However, this conclusion does not hold when considering the entire Geostationary Lightning Mapper–Bolides data set associated with confirmed events. For a country the size of Brazil, the expected frequency of events with impact energy ≥1 kt is one every 19–20 yr. The distribution of superbolide energy in the CNEOS data base, modelled using the generalized Pareto distribution, estimates an average recurrence period of one $\ge 440$ kt event every 80 yr and one ≥15 000 kt event every 1100 yr for Chelyabinsk- and Tunguska-like impacts, respectively. A significant negative correlation was found between altitude and the known total weight of the meteorites associated with the CNEOS superbolides, suggesting that higher altitudes favour greater fragment dispersion. A comparison of the velocity and altitude distributions between BRAMON meteors and CNEOS superbolides indicates that extreme events such as Tunguska probably do not have a cometary origin.