Mare versus highland lunar impact flash light curve dichotomy

Abstract

We perform a comprehensive analysis of lunar impact flash (LIF) light curve shapes and their dependence on the lunar terrain, using the large sample of LIFs detected by NELIOTA over the last 9 years. We classified 124 multi-frame light curves into mare, highland and `border' regions. Subsequently, we derived analytical expressions for single-size and dual-size ejecta cooling models, which were fitted to the observational data to estimate their physical properties. While impacts on both terrains yield similar peak magnitude distributions, their decay behaviour differs significantly; highland LIFs exhibit a shallower and longer-lasting decay compared to mare flashes, which are faster and steeper. The dual-size model suggests this extended duration is primarily driven by the fine droplets of the ejecta. The profile and duration of the LIF light curves represent the initial stages of the impact cratering process. The observed dichotomy between highland and mare LIFs demonstrates that the initial stages of the impact cratering process are fundamentally dependent on lunar lithology.

9 pages, 6 figures, 5 tables; accepted to A&A Letters

References in corpus (13)

• SciPy 1.0--Fundamental Algorithms for Scientific Computing in Python
• emcee: The MCMC Hammer
• The Flux of Kilogram-Sized Meteoroids from Lunar Impact Monitoring
• Lunar impact flashes from Geminids, analysis of luminous efficiencies and the flux of large meteoroids on Earth
• Analysis of Moon impact flashes detected during the 2012 and 2013 Perseids
• Temperatures of lunar impact flashes: mass and size distribution of small impactors hitting the Moon
• NELIOTA: The wide-field, high-cadence lunar monitoring system at the prime focus of the Kryoneri telescope
• MIDAS: Software for the detection and analysis of lunar impact flashes
• NELIOTA: Methods, statistics and results for meteoroids impacting the Moon
• NELIOTA: First temperature measurement of lunar impact flashes
• Multiwavelength observations of a bright impact flash during the January 2019 total lunar eclipse
• Analysis of the September $\epsilon$-Perseid outburst in 2013
• NELIOTA: New results and updated statistics after 6.5 years of lunar impact flashes monitoring