Rotation state, colors, and albedo of the mission-accessible tiny near-Earth asteroid 2001 QJ₁₄₂

¹ Université Côte d’Azur, Observatoire de la Côte d’Azur, CNRS, Laboratoire Lagrange, Bd de l’Observatoire, CS 34229, 06304 Nice Cedex 4, France
² Institute of Astronomy, Graduate School of Science, The University of Tokyo, 2-21-1 Osawa, Mitaka, Tokyo 181-0015, Japan
³ Department of Astronomy, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
⁴ Institute of Astronomy, V.N. Karazin Kharkiv National University, 35 Sumska Str., Kharkiv 61022, Ukraine
⁵ Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822, USA
⁶ ESA NEO Coordination Centre, Planetary Defence Office, Largo Galileo Galilei 1, 00044 Frascati (RM), Italy

^★ Corresponding author; e-mail: jbeniyama@oca.eu

Received: 7 July 2024
Accepted: 28 August 2024

Abstract

Context. Characterizing mission-accessible asteroids using telescopic observations is fundamental for target-selection and planning for spacecraft missions. Near-Earth asteroids on Earth-like orbits are of particular importance for applications such as asteroid mining. Aims. 2001 QJ₁₄₂ is a tiny (D ≤ 100 m) near-Earth asteroid on an Earth-like orbit with a semimajor axis of 1.06 au, orbital eccentricity of 0.09, and orbital inclination of 3.10°. We aim to characterize 2001 QJ₁₄₂ using ground-based observations with future spacecraft missions in mind.

Methods. We performed visible multicolor photometry of 2001 QJ₁₄₂ using the TriCCS on the Seimei 3.8 m telescope in February 2024. We also revisited the images taken with the Suprime-Cam on the Subaru 8.2 m telescope in August 2012.

Results. Visible color indices of 2001 QJ₁₄₂ indicate that 2001 QJ₁₄₂ is a C- or X-complex asteroid. We detect a possible fast rotation with a period of about 10 min, which is consistent with a previous report. The geometric albedo of 2001 QJ₁₄₂ is derived to be about 0.3 from a slope of its photometric phase curve, which is consistent with an albedo derived from thermal observations with updated physical quantities. A straightforward interpretation is that 2001 QJ₁₄₂ is either an E- or M-type asteroid, although surface properties of such tiny fast-rotating asteroids are not well understood.

Conclusions. We infer that 2001 QJ₁₄₂ is a fast-rotating mission-accessible E- or M-type near-Earth asteroid. More characterizations of tiny asteroids are particularly important for a deeper understanding of their nature.