Rotation acceleration of asteroids (10115) 1992 SK, (1685) Toro, and (1620) Geographos due to the YORP effect
Ďurech J. Vokrouhlický D. Pravec P. Krugly Y.N. Kim M.-J. Polishook D. Ayvazian V.V. Bonev T. Choi Y.-J. Datashvili D.G. Donchev Z. Ehgamberdiev S.A. Hornoch K. Inasaridze R.Y. Kapanadze G.V. Kim D.-H. Kučáková H. Kusakin A.V. Kušnirák P. Lee H.-J. Molotov I.E. Moon H.-K. Mykhailova S.S. Nikolenko I.V. Novichonok A. Oey J. Omarov C.T. Pollock J.T. Reva I.V. Rumyantsev V.V. Zhornichenko A.A.
1 January 2022EDP Sciences
Astronomy and Astrophysics
2022#657
Context. The rotation state of small asteroids is affected by the Yarkovsky-OKeefe-Radzievskii-Paddack (YORP) effect, which is a net torque caused by solar radiation directly reflected and thermally reemitted from the surface. Due to this effect, the rotation period slowly changes, which can be most easily measured in light curves because the shift in the rotation phase accumulates over time quadratically. Aims. By new photometric observations of selected near-Earth asteroids, we want to enlarge the sample of asteroids with a detected YORP effect. Methods. We collected archived light curves and carried out new photometric observations for asteroids (10115) 1992 SK, (1620) Geographos, and (1685) Toro. We applied the method of light curve inversion to fit observations with a convex shape model. The YORP effect was modeled as a linear change of the rotation frequency υ= dω/dt dt and optimized together with other spin and shape parameters. Results. 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. Conclusions. 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 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.
Methods: data analysis , Minor planets, asteroids: general , Techniques: photometric
Text of the article Перейти на текст статьи
Astronomical Institute, Faculty of Mathematics and Physics, Charles University, V Holešovičkách 2, Prague 8, 180, 00, Czech Republic
Astronomical Institute, Academy of Sciences of the Czech Republic, Fričova 1, Ondřejov, 251, 65, Czech Republic
Institute of Astronomy of V.N. Karazin Kharkiv National University, 35 Sumska Str., Kharkiv, 61022, Ukraine
Korea Astronomy and Space Science Institute, 776, Daedeokdae-ro, Yuseong-gu, Daejeon, 34055, South Korea
Faculty of Physics, Weizmann Institute of Science, 234 Herzl St., Rehovot, 7610001, Israel
Kharadze Abastumani Astrophysical Observatory, Ilia State University, 3/5 K. Cholokoshvili Av., Tbilisi, 0162, Georgia
Institute of Astronomy and NAO, Bulgarian Academy of Sciences, 72 Tsarigradsko Chaussee Blvd., Sofia, 1784, Bulgaria
University of Science and Technology, South Korea
Ulugh Beg Astronomical Institute, 33 Astronomicheskaya Str., Tashkent, 100052, Uzbekistan
Samtskhe-Javakheti State University, 113 Rustaveli Str., Akhaltsikhe, 0080, Georgia
Chungbuk National University, 1 Chungdae-ro, Seowon-gu, Chungbuk, Cheongju, 28644, South Korea
Fesenkov Astrophysical Institute, 23 Observatory, Almaty, 050020, Kazakhstan
Keldysh Institute of Applied Mathematics, RAS, 4 Miusskaya sq., Moscow, 125047, Russian Federation
Institute of Astronomy, RAS, 48 Pyatnitskaya str., Moscow, 119017, Russian Federation
Petrozavodsk State University, 33 Lenin Str., Petrozavodsk, 185910, Russian Federation
Blue Mountains Observatory, 94 Rawson Pde., Leura, 2780, NSW, Australia
Physics and Astronomy Department, Appalachian State University, 525 Rivers St, Boone, 28608, NC, United States
Crimean Astrophysical Observatory
Astronomical Institute
Astronomical Institute
Institute of Astronomy of V.N. Karazin Kharkiv National University
Korea Astronomy and Space Science Institute
Faculty of Physics
Kharadze Abastumani Astrophysical Observatory
Institute of Astronomy and NAO
University of Science and Technology
Ulugh Beg Astronomical Institute
Samtskhe-Javakheti State University
Chungbuk National University
Fesenkov Astrophysical Institute
Keldysh Institute of Applied Mathematics
Institute of Astronomy
Petrozavodsk State University
Blue Mountains Observatory
Physics and Astronomy Department
Crimean Astrophysical Observatory
10 лет помогаем публиковать статьи Международный издатель
Книга Публикация научной статьи Волощук 2026 Book Publication of a scientific article 2026