(704) Interamnia: a transitional object between a dwarf planet and a typical irregular-shaped minor body

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216208%3A11320%2F20%3A10423526" target="_blank" >RIV/00216208:11320/20:10423526 - isvavai.cz</a>

Result on the web

<a href="https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Oz5veqDHM6" target="_blank" >https://verso.is.cuni.cz/pub/verso.fpl?fname=obd_publikace_handle&handle=Oz5veqDHM6</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1051/0004-6361/201936639" target="_blank" >10.1051/0004-6361/201936639</a>

Result language

angličtina

Original language name

(704) Interamnia: a transitional object between a dwarf planet and a typical irregular-shaped minor body

Original language description

Context. With an estimated diameter in the 320-350 km range, (704) Interamnia is the fifth largest main belt asteroid and one of the few bodies that fills the gap in size between the four largest bodies with D &gt; 400 km (Ceres, Vesta, Pallas and Hygiea) and the numerous smaller bodies with diameter &lt;= 200 km. However, despite its large size, little is known about the shape and spin state of Interamnia and, therefore, about its bulk composition and past collisional evolution. Aims. We aimed to test at what size and mass the shape of a small body departs from a nearly ellipsoidal equilibrium shape (as observed in the case of the four largest asteroids) to an irregular shape as routinely observed in the case of smaller (D &lt;= 200 km) bodies. Methods. We observed Interamnia as part of our ESO VLT/SPHERE large program (ID: 199.C-0074) at thirteen different epochs. In addition, several new optical lightcurves were recorded. These data, along with stellar occultation data from the literature, were fed to the All-Data Asteroid Modeling algorithm to reconstruct the 3D-shape model of Interamnia and to determine its spin state. Results. Interamnia&apos;s volume-equivalent diameter of 332 6 km implies a bulk density of rho = 1.98 +/- 0.68 g cm(-3), which suggests that Interamnia - like Ceres and Hygiea - contains a high fraction of water ice, consistent with the paucity of apparent craters. Our observations reveal a shape that can be well approximated by an ellipsoid, and that is compatible with a fluid hydrostatic equilibrium at the 2 sigma level. Conclusions. The rather regular shape of Interamnia implies that the size and mass limit, under which the shapes of minor bodies with a high amount of water ice in the subsurface become irregular, has to be searched among smaller (D &lt;= 300 km) less massive (m &lt;= 3 x 10(19) kg) bodies.

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

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

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

Publication year

2020

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

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Volume of the periodical

633

Issue of the periodical within the volume

leden

Country of publishing house

FR - FRANCE

Number of pages

17

Pages from-to

A65

UT code for WoS article

000507285800001

EID of the result in the Scopus database

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