TY - JOUR
T1 - (704) Interamnia: a transitional object between a dwarf planet and a typical irregular-shaped minor body
A1 - Hanuš, J.
A1 - Vernazza, P.
A1 - Viikinkoski, M.
A1 - Ferrais, M.
A1 - Rambaux, N.
A1 - Podlewska-Gaca, E.
A1 - Drouard, A.
A1 - Jorda, L.
A1 - Jehin, E.
A1 - Carry, B.
A1 - Marsset, M.
A1 - Marchis, F.
A1 - Warner, B.
A1 - Behrend, R.
A1 - Asenjo, V.
A1 - Berger, N.
A1 - Bronikowska, M.
A1 - Brothers, T.
A1 - Charbonnel, S.
A1 - Colazo, C.
A1 - Coliac, J. -F.
A1 - Duffard, R.
A1 - Jones, A.
A1 - Leroy, A.
A1 - Marciniak, A.
A1 - Melia, R.
A1 - Molina, D.
A1 - Nadolny, J.
A1 - Person, M.
A1 - Pejcha, O.
A1 - Riemis, H.
A1 - Shappee, B.
A1 - Sobkowiak, K.
A1 - Soldán, F.
A1 - Suys, D.
A1 - Szakats, R.
A1 - Vantomme, J.
A1 - Birlan, M.
A1 - Berthier, J.
A1 - Bartczak, P.
A1 - Dumas, C.
A1 - Dudziński, G.
A1 - Ďurech, J.
A1 - Castillo-Rogez, J.
A1 - Cipriani, F.
A1 - Fetick, R.
A1 - Fusco, T.
A1 - Grice, J.
A1 - Kaasalainen, M.
A1 - Kryszczynska, A.
A1 - Lamy, P.
A1 - Michalowski, T.
A1 - Michel, P.
A1 - Santana-Ros, T.
A1 - Tanga, P.
A1 - Vachier, F.
A1 - Vigan, A.
A1 - Witasse, O.
A1 - Yang, B.
JA - Astronomy and Astrophysics
Y1 - 2020
VL - 633
SP - A65
SN - 0004-6361
UR - https://ui.adsabs.harvard.edu/abs/2020A&A...633A..65H
KW - asteroids: individual: (704) Interamnia
KW - Astrophysics - Earth and Planetary Astrophysics
KW - methods: observational
KW - minor planets
KW - techniques: high angular resolution
KW - techniques: photometric
N2 - Context. With an estimated diameter in the 320-350 km range, (704)
M1 - ={Interamnia is the fifth largest main belt asteroid and one of the few
M1 - bodies that fills the gap in size between the four largest bodies with D
M1 - > 400 km (Ceres
M1 - Vesta
M1 - Pallas and Hygiea) and the numerous smaller
M1 - bodies with diameter ≤200 km. However
M1 - despite its large size
M1 - little is
M1 - known about the shape and spin state of Interamnia and
M1 - therefore
M1 - about
M1 - its bulk composition and past collisional evolution.
Aims: We
M1 - aimed to test at what size and mass the shape of a small body departs
M1 - from a nearly ellipsoidal equilibrium shape (as observed in the case of
M1 - the four largest asteroids) to an irregular shape as routinely observed
M1 - in the case of smaller (D ≤ 200 km) bodies.
Methods: We observed
M1 - Interamnia as part of our ESO VLT/SPHERE large program (ID: 199.C-0074)
M1 - at thirteen different epochs. In addition
M1 - several new optical
M1 - lightcurves were recorded. These data
M1 - along with stellar occultation
M1 - data from the literature
M1 - were fed to the All-Data Asteroid Modeling
M1 - algorithm to reconstruct the 3D-shape model of Interamnia and to
M1 - determine its spin state.
Results: Interamnia's volume-equivalent
M1 - diameter of 332 ± 6 km implies a bulk density of ρ = 1.98 ± 0.68 g
M1 - like Ceres and Hygiea
M1 - - contains a high fraction of water ice
M1 - consistent with the paucity of
M1 - apparent craters. Our observations reveal a shape that can be well
M1 - approximated by an ellipsoid
M1 - and that is compatible with a fluid
M1 - hydrostatic equilibrium at the 2σ level.
Conclusions: The rather
M1 - regular shape of Interamnia implies that the size and mass limit
M1 - under
M1 - which the shapes of minor bodies with a high amount of water ice in the
M1 - subsurface become irregular
M1 - has to be searched among smaller (D ≤ 300
M1 - km) less massive (m ≤ 3 × 1019 kg) bodies. The reduced
M1 - images are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr
M1 - (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-
M1 - bin/cat/J/A+A/633/A65 Based on observations made with ESO
M1 - Telescopes at the La Silla Paranal Observatory under program 199.C-0074
M1 - (PI: Vernazza).
M1 - 10.1051/0004-6361/201936639
M1 - eprint: arXiv:1911.13049}
ER -