Spins and shapes of 11 near-Earth asteroids observed within the NEOROCKS project

¹ Astronomical Institute ASCR, Fričova 298, Ondřejov 251 65, Czech Republic
² Institute of Astronomy, Charles University, V Holešovičkách 2, Prague 180 00, Czech Republic
³ Research Centre for Theoretical Physics and Astrophysics, Institute of Physics, Silesian University in Opava, Bezručovo nám. 13, Opava 746 01, Czech Republic
⁴ Ulugh Beg Astronomical Institute, 33 Astronomicheskaya St., Tashkent 100052, Uzbekistan
⁵ Heidelberg University, Department of Physics and Astronomy, Im Neuenheimer Feld 226, 69120 Heidelberg, Germany
⁶ National University of Uzbekistan, 4 Universitet St., Tashkent 100174, Uzbekistan
⁷ Modra Observatory, Department of Astronomy, Physics of the Earth, and Meteorology, FMPI UK, Mlynská dolina, Bratislava 84248, Slovakia
⁸ Lunar and Planetary Laboratory, University of Arizona, 1629 E University Blvd, Tucson, AZ, USA
⁹ Badlands Observatory, 12 Ash St., Quinn, SD 57775, USA
¹⁰ The University of Texas at Austin, Astronomy Department/McDonald Observatory, 1 University Station C1400, Austin, TX 78712-0259, USA
¹¹ Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9 3HJ, UK
¹² Instituto de Astrofísica e Ciências do Espaço, Departamento de Física, Universidade de Coimbra, 3040-004 Coimbra, Portugal
¹³ Astronomy Research Center, Research Institute of Basic Sciences, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul 08826, Korea

^★ Corresponding author; fatka@asu.cas.cz

Received: 19 March 2024
Accepted: 23 January 2025

Abstract

Context. The discovery rate of near-Earth asteroids (NEAs) has steadily increased over the past three decades, yet the physical characterization of these objects has not kept pace.

Aims. In an effort to help address this gap, we combined targeted photometric observations, archival data, and sparse photometric data from the Asteroid Terrestrial-impact Last Alert System (ATLAS) survey to extract as much information as possible about NEAs’ rotation rates, spin-axis orientations, and shapes.

Methods. We selected 17 NEAs with a potential for shape reconstruction and applied the light curve inversion method to derive their sidereal rotation periods, spin-axis directions, and convex shape models.

Results. We successfully determined unique spin and shape models for seven NEAs: (5189) 1990 UQ, (6569) Ondaatje, (7025) 1993 QA, (8566) 1996 EN, (86450) 2000 CK₃₃, the Hayabusa2# flyby target (98943) 2001 CC₂₁, and (512245) 2016 AU₈. For an additional four asteroids – (66251) 1999GJ₂, (137199) 1999KX₄, (276786) 2004 KD₁, and (495615) 2015 PQ₂₉₁ – we constrained their sidereal periods, spin-axis orientations, and in some cases, their shapes.

Conclusions. This study highlights the importance of integrating new photometric data with archival dense light curves and sparse observations to improve the physical characterization of NEAs, even when working with suboptimal datasets. We constructed 11 NEA models, contributing to the limited set of a few dozen models derived from space missions, radar observations, and light curve inversions.