Perseids 2018 - Analysis of Global Visual Data

The results presented here have been obtained in the Visual Workshop held during the IMC 2018 in Pezinok-Modra. The Workshop included a verification of data stored in IMO's current Visual Meteor Database (VMDB), was an application of the MetFns procedures and was meant as a training session. While there were no dust trail encounters expected in 2018, a stream filament was calculated to appear on August 12, close to 20h UT. The visual data (27650 Perseids reported by 201 observers within 1265.39 hours between August 5 and 21) show a clear signature of the filament, consisting of a minimum in the population index r=1.60±0.08 at solar longitude 139.797 degrees (2018 August 12, 19h47m UT) and a peak ZHR=134±13 at solar longitude approx. 139.773 degrees (2018 August 12, 19h11m UT). During the main (nodal) maximum the population index r varied between 1.75 and 1.95; the ZHR reached values in the range 80-90 in the period solar longitude 139.8 degrees to 140.2 degrees. The filament encounter is most obvious in the number density profile for larger meteoroids (≥ 10 mg) at solar longitude=139.78±0.02 degrees (2018 August 12, 19h21m UT).