Characterisation of the Perseid meteoroid stream through SPOSH observations between 2010–2016

Abstract

We have characterised the Perseid meteoroid stream from data acquired in a series of observing campaigns between 2010 and 2016. The data presented in this work were obtained by the Smart Panoramic Optical Sensor Head (SPOSH), an all-sky camera system designed to image faint transient noctilucent phenomena on dark planetary hemispheres. For the data reduction, a sophisticated software package was developed that utilises the high geometric and photometric quality of images obtained by the camera system. We identify 934 meteors as Perseids, observed over a long period between late July (∼124 • ) and mid-to-late August (∼147 • ). The maximum meteor activity contributing to the annual shower was found at λ = 140. • 08 ± 0. • 07. The radiant of the shower was estimated at RA = 47. • 2 and Dec = 57. • 5 with a median error of 0. • 6 and 0. • 2, respectively. The mean population index of the shower between solar longitudes of 120. • 68 and 145. • 19 was r = 2.36 ± 0.05, showing strong temporal variation. A predicted outburst in shower activity for the night of August 11-12, 2016 was confirmed, with a peak observed 12.75 hr before the annual maximum at 23:30 ± 15 UT. We measure a peak flux of 6.1 × 10 −4 km −2 hr −1 for meteoroids of mass 1.6 × 10 −2 g or more, appearing in the time period between 23:00 and 00:00 UT. We estimate the measured flux of the outburst meteoroids to be approximately twice as high as the annual meteoroid flux of the same mass. The population index of r = 2.19 ± 0.08, computed from the outburst Perseids in 2016, is higher than the value of r = 1.92 ± 0.06 derived from meteors observed in 2015 belonging to the annual Perseid shower which was active near the time of the outburst. A dust trail with an unusually high population index of r = 3.58 ± 0.24 was encountered in 2013 between solar longitudes 136. • 261 and 137. • 442. The relatively high r-value implies an encounter with a dust trail rich in low-mass particles.

A Reference Meteor Magnitude for Intercomparable Fluxes

“…Today, it is widely used within the meteor astronomy community (recent examples include Blaauw 2017; Margonis et al 2019;Molau 2022;Vida et al 2022). We review this method in Section 2.1.…”

Meteor phenomena in the atmosphere of Venus

“…Recent interest in detecting fast optical transients in the Earth's atmosphere from space has yielded two facility concepts suitable for the task: the Smart Panoramic Optical Sensor Head (SPOSH; Oberst et al, 2011;Christou et al, 2012) and the Joint Exploratory Missions for an Extreme Universe Space Observatory (JEM-EUSO; Haungs and the JEM-EUSO collaboration, 2015). Breadboard versions of SPOSH were successfully field-tested in a twostation configuration, completing a multi-year survey of the Perseid meteor shower (Margonis et al, 2019) while the JEM-EUSO study evolved into the Mini-EUSO demonstrator that has been systematically recording meteors from the International Space Station since 2019 (Bacholle et al, 2021;Coleman et al, 2023).…”