An advanced multipole model for (216) Kleopatra triple system
Identifikátory výsledku
Kód výsledku v IS VaVaI
<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F21%3A10437340" target="_blank" >RIV/00216208:11320/21:10437340 - isvavai.cz</a>
Výsledek na webu
<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=rjN_oBObaC" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=rjN_oBObaC</a>
DOI - Digital Object Identifier
<a href="http://dx.doi.org/10.1051/0004-6361/202140901" target="_blank" >10.1051/0004-6361/202140901</a>
Alternativní jazyky
Jazyk výsledku
angličtina
Název v původním jazyce
An advanced multipole model for (216) Kleopatra triple system
Popis výsledku v původním jazyce
Aims. To interpret adaptive-optics observations of (216) Kleopatra, we need to describe an evolution of multiple moons orbiting an extremely irregular body and include their mutual interactions. Such orbits are generally non-Keplerian and orbital elements are not constants. Methods. Consequently, we used a modified N-body integrator, which was significantly extended to include the multipole expansion of the gravitational field up to the order l = 10. Its convergence was verified against the 'brute-force' algorithm. We computed the coefficients C-lm, S-lm for Kleopatra's shape, assuming a constant bulk density. For Solar System applications, it was also necessary to implement a variable distance and geometry of observations. Our chi(2) metric then accounts for the absolute astrometry, the relative astrometry (second moon with respect to the first), angular velocities, and silhouettes, constraining the pole orientation. This allowed us to derive the orbital elements of Kleopatra's two moons. Results. Using both archival astrometric data and new VLT/SPHERE observations (ESO LP 199.C-0074), we were able to identify the true periods of the moons, P-1 = (1.822359 +/- 0.004156) d, P-2 = (2.745820 +/- 0.004820) d. They orbit very close to the 3:2 mean-motion resonance, but their osculating eccentricities are too small compared to other perturbations (multipole, mutual), meaning that regular librations of the critical argument are not present. The resulting mass of Kleopatra, m(1) = (1.49 +/- 0.16) x 10(-12) M-circle dot or 2.97 x 10(18) kg, is significantly lower than previously thought. An implication explained in the accompanying paper is that (216) Kleopatra is a critically rotating body.
Název v anglickém jazyce
An advanced multipole model for (216) Kleopatra triple system
Popis výsledku anglicky
Aims. To interpret adaptive-optics observations of (216) Kleopatra, we need to describe an evolution of multiple moons orbiting an extremely irregular body and include their mutual interactions. Such orbits are generally non-Keplerian and orbital elements are not constants. Methods. Consequently, we used a modified N-body integrator, which was significantly extended to include the multipole expansion of the gravitational field up to the order l = 10. Its convergence was verified against the 'brute-force' algorithm. We computed the coefficients C-lm, S-lm for Kleopatra's shape, assuming a constant bulk density. For Solar System applications, it was also necessary to implement a variable distance and geometry of observations. Our chi(2) metric then accounts for the absolute astrometry, the relative astrometry (second moon with respect to the first), angular velocities, and silhouettes, constraining the pole orientation. This allowed us to derive the orbital elements of Kleopatra's two moons. Results. Using both archival astrometric data and new VLT/SPHERE observations (ESO LP 199.C-0074), we were able to identify the true periods of the moons, P-1 = (1.822359 +/- 0.004156) d, P-2 = (2.745820 +/- 0.004820) d. They orbit very close to the 3:2 mean-motion resonance, but their osculating eccentricities are too small compared to other perturbations (multipole, mutual), meaning that regular librations of the critical argument are not present. The resulting mass of Kleopatra, m(1) = (1.49 +/- 0.16) x 10(-12) M-circle dot or 2.97 x 10(18) kg, is significantly lower than previously thought. An implication explained in the accompanying paper is that (216) Kleopatra is a critically rotating body.
Klasifikace
Druh
J<sub>imp</sub> - Článek v periodiku v databázi Web of Science
CEP obor
—
OECD FORD obor
10308 - Astronomy (including astrophysics,space science)
Návaznosti výsledku
Projekt
Výsledek vznikl pri realizaci vícero projektů. Více informací v záložce Projekty.
Návaznosti
P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)
Ostatní
Rok uplatnění
2021
Kód důvěrnosti údajů
S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů
Údaje specifické pro druh výsledku
Název periodika
Astronomy & Astrophysics
ISSN
0004-6361
e-ISSN
—
Svazek periodika
653
Číslo periodika v rámci svazku
září
Stát vydavatele periodika
FR - Francouzská republika
Počet stran výsledku
9
Strana od-do
A56
Kód UT WoS článku
000694212400004
EID výsledku v databázi Scopus
2-s2.0-85114801327