Evidence of a metal-rich surface for the asteroid (16) Psyche from interferometric observations in the thermal infrared
- Others:
- Max-Planck-Institut für Radioastronomie (MPIFR)
- UNS-CNRS-Observatoire de la Côte d'Azur ; UNS-CNRS-Observatoire de la Côte d'Azur
- Institut de Mécanique Céleste et de Calcul des Ephémérides (IMCCE) ; Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris ; Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Lille-Centre National de la Recherche Scientifique (CNRS)
- INAF - Osservatorio Astrofisico di Torino (OATo) ; Istituto Nazionale di Astrofisica (INAF)
Description
We describe the first determination of thermal properties and size of the M-type asteroid (16) Psyche from interferometric observations obtained with the Mid-Infrared Interferometric Instrument (MIDI) of the Very Large Telescope Interferometer. We used a thermophysical model to interpret our interferometric data. Our analysis shows that Psyche has a low macroscopic surface roughness. Using a convex 3-D shape model obtained by Kaasalainen et al. (2002, Icarus 159, 369-395), we derived a volume-equivalent diameter for (16) Psyche of 247 +- 25 km or 238 +- 24 km, depending on the possible values of surface roughness. Our corresponding thermal inertia estimates are 133 or 114 J.m-2.s-0.5.K-1, with a total uncertainty estimated to 40 J.m-2.s-0.5.K-1. They are among the highest thermal inertia values ever measured for an asteroid of this size. We consider this as a new evidence of a metal-rich surface for the asteroid (16) Psyche.
Abstract
45 pages (in referee and preprint format), 6 figures. Accepted for publication in Icarus.
Additional details
- URL
- https://hal.archives-ouvertes.fr/hal-00833226
- URN
- urn:oai:HAL:hal-00833226v1
- Origin repository
- UNICA