1. Radial Distribution of the Dust Comae of Comets 45P/Honda-Mrkos-Pajdu\u{s}\'akov\'a and 46P/Wirtanen
- Author
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Lejoly, C., Harris, W., Samarasinha, N., Mueller, B. E. A., Howell, E., Bodnarik, J., Springmann, A., Kareta, T., Sharkey, B., Noonan, J., Bedin, L. R., Bosch, J. -G., Brosio, A., Bryssinck, E., de Vanssay, J. -B., Hambsch, F. -J., Ivanova, O., Krushinsky, V., Lin, Z. -Y., Manzini, F., Maury, A., Moriya, N., Ochner, P., and Oldani, V.
- Subjects
Astrophysics - Earth and Planetary Astrophysics - Abstract
There was an unprecedented opportunity to study the inner dust coma environment, where the dust and gas are not entirely decoupled, of comets 45P/Honda-Mrkos-Pajdu\u{s}\'akov\'a (45P/HMP) from Dec. 26, 2016 - Mar. 15, 2017, and 46P/Wirtanen from Nov. 10, 2018 - Feb. 13, 2019, both in visible wavelengths. The radial profile slopes of these comets were measured in the R and HB-BC filters most representative of dust, and deviations from a radially expanding coma were identified as significant. The azimuthally averaged radial profile slope of comet 45P/HMP gradually changes from -1.81 $\pm$ 0.20 at 5.24 days pre-perihelion to -0.35 $\pm$ 0.16 at 74.41 days post perihelion. Contrastingly, the radial profile slope of 46P/Wirtanen stays fairly constant over the observed time period at -1.05 $\pm$ 0.05. Additionally, we find that the radial profile of 46P/Wirtanen is azimuthally dependent on the skyplane-projected solar position angle, while that of 45P/HMP is not. These results suggest that comet 45P/HMP and 46P/Wirtanen have vastly different coma dust environments and that their dust properties are distinct. As evident from these two comets, well-resolved inner comae are vital for detailed characterization of dust environments., Comment: 21 pages, 13 figures, to be published in the Planetary Science Journal
- Published
- 2021