Photometric and spectroscopic observations of Sycorax, satellite of Uranus

Citation
J. Romon et al., Photometric and spectroscopic observations of Sycorax, satellite of Uranus, ASTRON ASTR, 376(1), 2001, pp. 310-315
Citations number
32
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Space Sciences
Journal title
ASTRONOMY & ASTROPHYSICS
ISSN journal
1432-0746 → ACNP
Volume
376
Issue
1
Year of publication
2001
Pages
310 - 315
Database
ISI
SICI code
1432-0746(200109)376:1<310:PASOOS>2.0.ZU;2-N
Abstract
Sycorax is the brightest of the five irregular Uranian satellites recently discovered. These satellites are supposed to be captured bodies. We present visible and near-infrared photometry, as well as near-infrared spectroscop y of Sycorax. The overall shape of the spectrum is quite puzzling: it has a red slope in the visible (such as Centaurs and Transneptunian objects), wh ereas the reflectivity strongly decreases beyond 1 mum and is rather at ove r the near-infrared range. We were not able to reproduce the spectral behav iour of Sycorax using simple materials. A rotational effect is suggested to explain the shape of the spectrum. BVRIJ magnitudes have been measured ove r a period of 1 hour, with five V measurements which do not show any strong variation. So only a strong change in the magnitude between the V measurem ents and the J measurement (30 min later) could explain the shape of the sp ectrum, but further investigation is required to conclude.