We analysed visual observation data of the Tau Herculids collected between 2022 May 28 and June 1. The population index for the entire sample is 2.4. For the pre-peak period we find r=2.57+-0.23, the peak period yields r=2.38+-0.06. The ZHR maximum of the 1995 ejecta from comet Schwassmann-Wachmann3 (SW3) is found at 69.450 deg solar longitude (May 31, 05h04mUT, +-5min) with a ZHR=55+-7, corresponding to a spatial number density ND of approx. 380 meteoroids larger than 10mg in a cube with 1000km edge length. An earlier maximum occurred at 69.207 deg solar longitude (centred May 30, 23h UT) with a ZHR=18+-3 and is tentatively associated with SW3-ejecta from 1892. Effects of the radiant shift due to the large zenith attraction of about 10 deg for the radiant close to the horizon are discussed.
@article{arxiv.2209.12297,
title = {Tau Herculids 2022: Rate, number density, population index and geometrical effects from visual data},
author = {Jurgen Rendtel and Rainer Arlt},
journal= {arXiv preprint arXiv:2209.12297},
year = {2022}
}