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arXiv · 2004.07951

Measuring Fluxes of Meteor Showers with the NASA All-Sky Fireball Network

Abstract

We present an algorithm developed to measure the fluxes of major meteor showers as observed in NASA's All-Sky Fireball Network cameras. Measurements of fluxes from the All-Sky cameras not only improve the Meteoroid Environment Office's (MEO's) ability to provide accurate risk assessments from major showers, but also allows the mass distribution of meteoroids within the shower to be constrained. This algorithm accounts for the shower-specific and event-specific exposure time and collecting area of the sky for nights where sufficiently large samples of shower meteors ($\sim 30$ or more from the shower) are observed. The fluxes derived from the All-Sky Fireball Network for the 2015 Geminid, 2016 Perseid and Quadrantid, 2017 Orionid, and 2018 Leonid shower peaks are calculated. All five of these shower fluxes show excellent agreement with expectations from independent measurements at different mass and luminosity limits. For four of these five showers, the measured mass indices are significantly shallower than what is currently assumed by the NASA Meteoroid Environment Office's (MEO's) annual meteor shower forecast. A direct comparison between forecasted and measured fluxes at limiting masses of $\sim 1 \thinspace \mathrm{g}$ shows good agreement for the three showers for which the observations took place near their peak activity.

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Steven Ehlert, Rhiannon Blaauw Erskine. 2020-04-16. Measuring Fluxes of Meteor Showers with the NASA All-Sky Fireball Network. https://doi.org/10.1016/j.pss.2020.104938

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