The role of astronomical silicates during a cometary outburst ^⋆

Abstract

This paper presents a new approach to analyzing the change of cometary brightness. In our considerations, we assume that astronomical silicates (dust agglomerates) and gas are present in the coma. This assumption is a consequence of the analysis of the result observed during the Rosetta mission to comet 67P/Churyumov-Gerasimenko (abbreviated 67P/Ch-G). The dimensions of these agglomerates can be up to several centimeters. However, the large ones are few compared to particles with dimensions of several micrometers. This paper presents the results of calculations on the change in hypothetical comet brightness as a result of its outburst. The calculations take into account the percentage of carbonaceous particles and silicates rich in magnesium.

The Evolution of the Nucleus Surface in the Context of the Change in the Brightness of a Comet*

“…One of the most interesting manifestations of cometary activity is rapid changes in the brightness of these celestial bodies, i.e., a cometary outburst. When we talk about a cometary outburst, we mean an increase in its brightness usually by several magnitudes (Cabot et al 1996;Enzian et al 1997;Ivanova et al 2011;Gronkowski & Wesołowski 2012, 2015a, 2016Miles 2016;Wesołowski & Gronkowski 2018a;Wesołowski 2020bWesołowski , 2021bWesołowski , 2021cWesołowski , 2022Wesołowski et al 2020bWesołowski et al , 2020c. We can present the course of a cometary outburst based on four stages: quiet phase (before the outburst), the outburst phase and the phase after the outburst, achieving a brightness comparable to the pre-outburst phase (see Wesołowski 2021a).…”