Modeling the past and future activity of the Halleyid meteor showers

A Egal,M Campbell-Brown,P G Brown,P Wiegert,D Vida

doi:10.1051/0004-6361/202038953

Abstract

Context.We present a new numerical model of theη-Aquariid and Orionid meteor showers.Aims.The model investigates the origin, variability, and age of theη-Aquariid and Orionid apparitions from 1985 to the present day in order to forecast their activity over the next several decades.Methods.Through the numerical integration of millions of simulated meteoroids and a custom-made particle weighting scheme, we model the characteristics of everyη-Aquariid and Orionid apparition between 1985 and 2050. The modeled showers are calibrated using 35 yr of meteor observations, including the shower activity profiles and interannual variability.Results.Our model reproduces the general characteristics of the present-dayη-Aquariids and part of the Orionid activity. Simulations suggest that the age of theη-Aquariids somewhat exceeds 5000 yr, while a greater fraction of the Orionids is composed of older material. The 1:6 mean motion resonance with Jupiter plays a major role in generating some (but not all) Halleyid stream outbursts. We find consistent evidence for a periodicity of 11.8 yr in both the observations and modeled maximum meteor rates for the Orionids. Weaker evidence of a 10.7 yr period in the peak activity for theη-Aquariids needs to be investigated with future meteor observations. The extension of our model to future years predicts no significant Orionid outbursts through 2050 and four significantη-Aquariid outbursts, in 2023, 2024, 2045, and 2046.

Highlights

In recent years, thanks to modern numerical simulations of meteoroid streams, the timing of meteor outbursts has reached unprecedented accuracy (e.g., Asher 1999)
In the following subsections, we investigate the agreement of our simulated activity profiles with video, visual, and radar observations of the η-Aquariid and Orionid meteor showers presented in Egal et al (2020)
The simulated activity profiles were scaled to the observations of the η-Aquariid shower, and the same scaling factor was applied to the modeled Orionid profile

Summary

Introduction

Thanks to modern numerical simulations of meteoroid streams, the timing of meteor outbursts has reached unprecedented accuracy (e.g., Asher 1999). Reliable estimates of meteor shower duration and intensity are less robust (Janches et al 2020). This is due to both a lack of measurement of the parent body’s past activity and a lack of long-term, consistent records of the resulting meteor showers. The modeling of comet 1P/Halley and Halleyid meteor showers, namely the η-Aquariids and Orionid, suffers from these observational limitations. The lack of consistent observations of the Halleyids (and especially of the η-Aquariids) has hampered development and validation of new models of the shower (e.g., see Sekhar & Asher 2014)

Objectives

Results

Conclusion