Shape and spin-state model of tumbling asteroid (319) Leona

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F25%3A10510224" target="_blank" >RIV/00216208:11320/25:10510224 - isvavai.cz</a>

Výsledek na webu

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=m9M9F6vFio" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=m9M9F6vFio</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/202554005" target="_blank" >10.1051/0004-6361/202554005</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Shape and spin-state model of tumbling asteroid (319) Leona

Popis výsledku v původním jazyce

Context. Stellar occultations by asteroids observed from several stations are routinely used to reconstruct the asteroid&apos;s sky-plane projections. Together with the asteroid&apos;s shape model reconstructed from photometry, such occultations enable us to precisely determine its size and reveal details of its shape. When reducing occultation timings, the usual assumption is that the star has a negligible angular diameter compared to the asteroid, so it is modeled as a point source. The occultation of Betelgeuse (alpha Orionis) by asteroid (319) Leona on 12 December 2023 was a rare exception - the apparent angular diameter of the star was similar to 50 mas, about the same as that of the asteroid. Aims. This work aimed to reconstruct the shape and spin model of asteroid Leona. Then, the projection of that model for the time of the occultation can be computed, which is necessary to interpret the occultation timings and infer valuable information about Betelgeuse itself. Methods. We collected available photometric data of Leona, carried out new observations, and reconstructed a unique convex shape model. Using three other occultations observed in 2023, we scaled this convex model. We also reconstructed an alternative nonconvex model with the same spin parameters and size but showing some surface details that explain better one of the occultations. Results. We confirmed the tumbling rotation state of Leona and uniquely determined the rotation period P-psi = 1172.2 +/- 0.3 h and the precession period P-phi = 314.27 +/- 0.02 h. The volume-equivalent diameter determined by occultations is 59.1 +/- 0.9 km. The reconstructed shape model of Leona enabled us to compute its sky-plane projection for the time of the Betelgeuse occultation. Conclusions. A reliable shape model with accurate dimensions and accurate rotation and precession periods has been reconstructed for slowly tumbling asteroid Leona. It can be used to interpret the observed occultation of Betelgeuse by Leona.

Název v anglickém jazyce

Shape and spin-state model of tumbling asteroid (319) Leona

Popis výsledku anglicky

Context. Stellar occultations by asteroids observed from several stations are routinely used to reconstruct the asteroid&apos;s sky-plane projections. Together with the asteroid&apos;s shape model reconstructed from photometry, such occultations enable us to precisely determine its size and reveal details of its shape. When reducing occultation timings, the usual assumption is that the star has a negligible angular diameter compared to the asteroid, so it is modeled as a point source. The occultation of Betelgeuse (alpha Orionis) by asteroid (319) Leona on 12 December 2023 was a rare exception - the apparent angular diameter of the star was similar to 50 mas, about the same as that of the asteroid. Aims. This work aimed to reconstruct the shape and spin model of asteroid Leona. Then, the projection of that model for the time of the occultation can be computed, which is necessary to interpret the occultation timings and infer valuable information about Betelgeuse itself. Methods. We collected available photometric data of Leona, carried out new observations, and reconstructed a unique convex shape model. Using three other occultations observed in 2023, we scaled this convex model. We also reconstructed an alternative nonconvex model with the same spin parameters and size but showing some surface details that explain better one of the occultations. Results. We confirmed the tumbling rotation state of Leona and uniquely determined the rotation period P-psi = 1172.2 +/- 0.3 h and the precession period P-phi = 314.27 +/- 0.02 h. The volume-equivalent diameter determined by occultations is 59.1 +/- 0.9 km. The reconstructed shape model of Leona enabled us to compute its sky-plane projection for the time of the Betelgeuse occultation. Conclusions. A reliable shape model with accurate dimensions and accurate rotation and precession periods has been reconstructed for slowly tumbling asteroid Leona. It can be used to interpret the observed occultation of Betelgeuse by Leona.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10308 - Astronomy (including astrophysics,space science)

Projekt

<a href="/cs/project/GA22-17783S" target="_blank" >GA22-17783S: V množství je síla - Využití sítě dalekohledů Unistellar eVscope občanských vědců pro studium planetek</a><br>

Návaznosti

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

Rok uplatnění

2025

Kód důvěrnosti údajů

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

Název periodika

Astronomy &amp; Astrophysics

ISSN

0004-6361

e-ISSN

1432-0746

Svazek periodika

696

Číslo periodika v rámci svazku

duben

Stát vydavatele periodika

FR - Francouzská republika

Počet stran výsledku

9

Strana od-do

A76

Kód UT WoS článku

001459780300027

EID výsledku v databázi Scopus

2-s2.0-105007642233