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Luminous efficiency is a necessary parameter for determining meteoroid mass from optical emission.Despite this importance, it is very poorly known, with previous results varying by up to two orders of magnitude for a given speed. We present the most recent study of luminous efficiency values determined with modern high-resolution instruments, by directly comparing dynamic and photometric meteoroid masses. Fifteen non-fragmenting meteoroids were used, with a further five clearly fragmenting events for comparison. Twelve of the fifteen non-fragmenting meteoroids had luminous efficiencies less than 1%, while the fragmenting meteoroids had upper limits of a few tens of percent.No clear trend with speed was seen, but there was a weak negative trend of luminous efficiency on meteoroid mass, implying that smaller meteoroids radiate more efficiently.

The luminous efficiency of meteors is poorly known, but critical for determining the meteoroid mass. We present an uncertainty analysis of the luminous efficiency as determined by the classical ablation equations, and suggest a possible method for determining the luminous efficiency of real meteor events. We find that a two-term exponential fit to simulated lag data is able to reproduce simulated luminous efficiencies reasonably well.

Twenty-one meteors showing double peaked light curves were analysed with observations collected with the Canadian Automated Meteor Observatory tracking system. Each event has orbital information, photometry, and at least one high-resolution observation. Two distinct light curve shapes were found: sudden double peaked curves, and smooth double peaked curves. The sudden peaked curves were produced by objects on asteroidal orbits and mostly showed noticeable fragmentation, while the smooth peaked curves were produced by cometary meteoroids and predominantly showed little to no visible fragmentation. An attempt to model these meteors as single bodies with two chemical components was unsuccessful, implying that fragmentation must be included in meteoroid ablation models.

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