Rotation acceleration of asteroids (10115) 1992 SK, (1685) Toro, and (1620) Geographos due to the YORP effect

0552552 - ASÚ 2023 RIV FR eng J - Journal Article
Ďurech, J. - Vokrouhlický, D. - Pravec, Petr - Hornoch, Kamil - Kučáková, Hana - Kušnirák, Peter … Total 31 authors
Rotation acceleration of asteroids (10115) 1992 SK, (1685) Toro, and (1620) Geographos due to the YORP effect.
Astronomy & Astrophysics. Roč. 657, January (2022), č. článku A5. ISSN 0004-6361. E-ISSN 1432-0746
R&D Projects: GA ČR(CZ) GA20-04431S
Institutional support: RVO:67985815
Keywords : minor planets * asteroid * data analysis
OECD category: Astronomy (including astrophysics,space science)
Impact factor: 6.5, year: 2022
Method of publishing: Open access with time embargo
https://doi.org/10.1051/0004-6361/202141844

By new photometric observations of selected near-Earth asteroids, we want to enlarge the sample of asteroids with a detected YORP effect. We detected the acceleration υ = (8.3 ± 0.6) × 10−8 rad d−2 of the rotation for asteroid (10115) 1992 SK. This observed value agrees well with the theoretical value of YORP-induced spin-up computed for our shape and spin model. For (1685) Toro, we obtained υ = (3.3 ± 0.3) × 10−9 rad d−2, which confirms an earlier tentative YORP detection. For (1620) Geographos, we confirmed the previously detected YORP acceleration and derived an updated value of υ with a smaller uncertainty. We also included the effect of solar precession into our inversion algorithm, and we show that there are hints of this effect in Geographos' data. The detected change of the spin rate of (10115) 1992 SK has increased the total number of asteroids with YORP detection to ten. In all ten cases, the dω∕dt value is positive, so the rotation of these asteroids is accelerated. It is unlikely to be just a statistical fluke, but it is probably a real feature that needs to be explained.
Permanent Link: http://hdl.handle.net/11104/0330953