Modeling Sublimation Dynamics and Dust Propagation of Comet 17P/Holmes During its 2007 Outburst

Abstract

We present a numerical modeling approach for the sublimation flux and dust particle propagation associated with the 2007 outburst of comet 17P/Holmes. This study integrates sublimation physics, effects of particle size and bulk density, and the gravitational and radiative dynamics affecting ejected particles. The model is supported by continued ground-based observations of the comet's dust trail and offers predictions for its long-term evolution. We discuss the results in the context of ongoing observational campaigns and implications for future monitoring of similar cometary outbursts.

1. Introduction

The mega-outburst of comet 17P/Holmes in October 2007 provided a unique opportunity to study dust and gas ejection processes and long-term dynamical evolution of these ejection events. This work focuses on modeling the sublimation-driven mass loss, analyzing the physical properties of ejected material, and simulating the propagation of dust particles influenced by gravitational and radiative forces.

2. Modeling of Sublimation Flux

To estimate the total ejected mass, we developed a numerical model based on observational data, employing Pogson’s law to convert photometric data to mass estimates (Gritsevich et al. 2025). The model accounts for three sublimation regimes: i) dust-covered porous agglomerates, ii) directly exposed porous agglomerates, and iii) sublimation corrected using an anomalous evaporation coefficient. These cases represent varying surface conditions, affecting the sublimation efficiency and consequent dust ejection.

3. Effects of Particle Size and Bulk Density

Outburst events release both gas and dust; however, dust dominates the scattering signal and is thus used as the primary proxy for estimating ejected mass. We simulate mass loss under different sublimation fluxes, focusing on porous ice, organic, and dust agglomerates, each with a 50% active surface fraction. These scenarios enable exploration of the influence of particle composition, size distribution, and density on the mass flux during the outburst phase.

4. Dust Propagation Modeling

A Monte Carlo-based dust dynamics model is constructed to simulate the trajectory and distribution of particles released during the 2007 outburst. The simulation includes solar radiation pressure, planetary perturbations from Venus, Earth-Moon system, Mars, Jupiter, Saturn, and the self-gravity of the comet itself (Gritsevich et al. 2022). The modeling framework utilizes the Orekit Java library and is augmented by Python tools employing the Skyfield library to calculate 3D trail positions (Nissinen et al. 2023b). These tools correct for Earth topography, light-time delay, and atmospheric refraction, with all computations referenced to the J2000 epoch.

5. Observational Campaigns

Continued observations of the 17P/Holmes dust trail provide critical data for model validation. Ground-based telescopes using visible-light imaging and differential photometry techniques such as image subtraction have successfully detected the trail. The first detection occurred in February 2013 at the southern node (Lyytinen et al. 2013), followed by a second campaign targeting the northern node from 2014 through 2015. Recent observations confirm continued visibility of the trail at the northern node (Ryske et al. 2022; Nissinen et al. 2023a). Infrared observations are encouraged to further constrain particle size and composition.

6. Conclusions

This study provides a comprehensive framework for modeling cometary outbursts, from sublimation flux characterization to particle propagation and observational validation. The 2007 outburst of comet 17P/Holmes serves as a benchmark for refining models applicable to future events, improving our understanding of the physical processes driving cometary activity.

References

Gritsevich, M., Nissinen, M., Oksanen, A., Suomela, J., Silber, E. A. (2022). Evolution of the dust trail of comet 17P/Holmes. MNRAS, 513, 2201–2214. https://doi.org/10.1093/mnras/stac822

Gritsevich, M., Wesołowski, M., Castro-Tirado, A. J. (2025). Mass of particles released by comet 12P/Pons-Brooks during 2023–2024 outbursts. MNRAS, 538, 470–479. https://doi.org/10.1093/mnras/staf219

Lyytinen, E., Nissinen, M., Lehto, H. J. (2013). Journal of the International Meteor Organization, 41, 77

Nissinen, M., Gritsevich, M., Ryske, J. (2023a). Recent Observations of the 17P/Holmes Dust Trail. 54th Lunar and Planetary Science Conference (LPI Contrib. No. 2806)

Nissinen, M., & Gritsevich, M. (2023b). Instructions for Ongoing Observations of the Dust Trail from the 2007 Outburst of Comet 17P/Holmes. Zenodo. https://doi.org/10.5281/zenodo.8319474

Ryske, J., Gritsevich, M., Nissinen, M. (2022). Validation of the Dust Trail kit model with the recent observations of the comet 17P/Holmes dust trail (February –March 2022), Europlanet Science Congress 2022, Granada, Spain, 18–23 Sep 2022, EPSC2022-60. https://doi.org/10.5194/epsc2022-60