(704) Interamnia: A transitional object between a dwarf planet and a typical irregular-shaped minor body
Authors:
- J. Hanuš,
- P. Vernazza,
- M. Viikinkoski,
- M. Ferrais,
- N. Rambaux,
- Edyta Podlewska-Gaca,
- A. Drouard,
- L. Jorda,
- E. Jehin,
- B. Carry,
- M. Marsset,
- F. Marchis,
- B. Warner,
- R. Behrend,
- V. Asenjo,
- N. Berger,
- Małgorzata Bronikowska,
- T. Brothers,
- S. Charbonnel,
- C. Colazo,
- J.-F. Coliac,
- R. Duffard,
- A. Jones,
- A. Leroy,
- Anna Marciniak,
- R. Melia,
- D. Molina,
- J. Nadolny,
- M. Person,
- O. Pejcha,
- H. Riemis,
- B. Shappee,
- K. Sobkowiak,
- F. Soldán,
- D. Suys,
- R. Szakats,
- J. Vantomme,
- M. Birlan,
- J. Berthier,
- Przemysław Paweł Bartczak,
- C. Dumas,
- Grzegorz Piotr Dudziński,
- J. D Urech,
- J. Castillo-Rogez,
- F. Cipriani,
- R. Fetick,
- T. Fusco,
- J. Grice,
- M. Kaasalainen,
- Agnieszka Kryszczyńska,
- P. Lamy,
- Tadeusz Michał Michałowski,
- P. Michel,
- Antonio Santana-Ros,
- P. Tanga,
- F. Vachier,
- A. Vigan,
- O. Witasse,
- B. Yang
Abstract
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 >400 km (Ceres, Vesta, Pallas and Hygiea) and the numerous smaller bodies with diameter 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 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 s volume-equivalent diameter of 332 6 km implies a bulk density of = 1.98 0.68 g cm3, 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 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 300 km) less massive (m 3 1019 kg) bodies.
- Record ID
- UAMd3bf7491fed444998300ca933d0b6824
- Author
- Journal series
- Astronomy & Astrophysics, ISSN 0004-6361, e-ISSN 1432-0746
- Issue year
- 2020
- Vol
- 633
- Pages
- 1-17
- Article number
- A65
- ASJC Classification
- ;
- DOI
- DOI:10.1051/0004-6361/201936639 Opening in a new tab
- Language
- (en) English
- Score (nominal)
- 140
- Score source
- journalList
- Score
- = 140.0, 21-05-2022, ArticleFromJournal
- Publication indicators
- = 5; = 4; = 10; : 2018 = 1.233; : 2019 (2 years) = 5.636 - 2019 (5 years) =5.395
- Citation count
- 11
Share
- Uniform Resource Identifier
- https://researchportal.amu.edu.pl/info/article/UAMd3bf7491fed444998300ca933d0b6824/
- URN
urn:amu-prod:UAMd3bf7491fed444998300ca933d0b6824
* presented citation count is obtained through Internet information analysis and it is close to the number calculated by the Publish or PerishOpening in a new tab system.