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

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F21%3A10437350" target="_blank" >RIV/00216208:11320/21:10437350 - isvavai.cz</a>

Alternative codes found

RIV/67985815:_____/22:00552552

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=b5boX0Ui.N" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=b5boX0Ui.N</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202141844" target="_blank" >10.1051/0004-6361/202141844</a>

Result language

angličtina

Original language name

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

Original language description

Context. The rotation state of small asteroids is affected by the Yarkovsky-O&apos;Keefe-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 upsilon equivalent to d omega/dt and optimized together with other spin and shape parameters. Results. We detected the acceleration upsilon = (8.3 +/- 0.6) x 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 upsilon = (3.3 +/- 0.3) x 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 upsilon 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&apos; 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 d omega/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.

Czech name

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Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

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OECD FORD branch

10308 - Astronomy (including astrophysics,space science)

Project

<a href="/en/project/GA20-04431S" target="_blank" >GA20-04431S: Physical and dynamical properties of space mission target asteroids, and their evolutionary paths</a><br>

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2021

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Astronomy &amp; Astrophysics

ISSN

0004-6361

e-ISSN

—

Volume of the periodical

leden

Issue of the periodical within the volume

říjen

Country of publishing house

FR - FRANCE

Number of pages

14

Pages from-to

A5

UT code for WoS article

000731753100004

EID of the result in the Scopus database

2-s2.0-85122227535