Rotation periods and shape asphericity in asteroid families based on TESS S1-S13 observations

¹ ELTE Eötvös Loránd University, Gothard Astrophysical Observatory, Szombathely, Hungary
e-mail: szgy@gothard.hu
² MTA-ELTE Exoplanet Research Group, 9700 Szombathely, Szent Imre h. u. 112, Hungary
³ Konkoly Observatory, Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network (ELKH), Konkoly Thege Miklós út 15-17, 1121 Budapest, Hungary
⁴ MTA-ELTE Lendület Milky Way Research Group, 9700 Szombathely Szent Imre h u 112, Hungary
⁵ MTA CSFK Lendület Near-Field Cosmology Research Group, Budapest, Hungary
⁶ ELTE Eötvös Loránd University, Institute of Physics, 1117 Pázmány Péter sétány 1/A, Budapest, Hungary
⁷ ELTE Eötvös Loránd University, Department of Astronomy, 1117, Pázmány Péter sétány 1/A, Budapest, Hungary
⁸ Sydney Institute for Astronomy, School of Physics A29, University of Sydney, NSW 2006, Australia

Received: 14 September 2021
Accepted: 25 January 2022

Abstract

Here we present the analysis of the distribution of rotation periods and light curve amplitudes based on 2859 family asteroids in 16 Main Belt families based on 9912 TESS asteroid light curves in the TSSYS-DR1 asteroid light curve database. We found that the distribution of the light curve properties follow a family-specific character in some asteroid families, including the Hungaria, Maria, Juno, Eos, Eucharis, and Alauda families. While in other large families, these distributions are in general very similar to each other. We confirm that older families tend to contain a larger fraction of more spheroidal, low-amplitude asteroids. We found that rotation period distributions are different in the cores and outskirts of the Flora and Maria families, while the Vesta, Eos, and Eunomia families lack this feature. We also confirm that very fast spinning asteroids are close to spherical (or spinning top shapes), and minor planets rotating slower than ≈11 h are also more spherical than asteroids in the 4–8 h period range and this group is expected to contain the most elongated bodies.