The Planetary Science Journal (Jan 2023)
Observational Characterization of Main-belt Comet and Candidate Main-belt Comet Nuclei
Abstract
We report observations of nine main-belt comets (MBCs) or candidate MBCs, most of which were obtained when the targets were apparently inactive. We find effective nucleus radii (assuming albedos of p _V = 0.05 ± 0.02) of r _n = (0.24 ± 0.05) km for 238P/Read, r _n = (0.9 ± 0.2) km for 313P/Gibbs, r _n = (0.6 ± 0.1) km for 324P/La Sagra, r _n = (1.0 ± 0.2) km for 426P/PANSTARRS, r _n = (0.5 ± 0.1) km for 427P/ATLAS, r _n 80% have r _n ≤ 1.0 km, pointing to an apparent physical preference toward small MBCs, where we suggest that Yarkovsky–O’Keefe–Radzievskii–Paddack spin-up may play a significant role in triggering and/or facilitating MBC activity.
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