Short-term rotational variability of eight KBOs from Sierra Nevada Observatory

Instituto de Astrofísica de Andalucía, CSIC, Apt 3004, 18080 Granada, Spain e-mail: ortiz@iaa.es

Received: 3 June 2005
Accepted: 29 September 2005

Abstract

In 2001, we started a CCD photometry programme to study the short-term variability of some of the brightest TNOs and Centaurs from the Sierra Nevada observatory. In this paper, we report our latest results on short-term rotational variability of 7 trans-neptunian objects: Orcus (2004 DW), 2002 AW₁₉₇, 2003 AZ₈₄, 2003 VS₂, 2002 VE₉₅, 2001 YH₁₄₀, 1996 TL₆₆, and a Centaur: 2003 CO₁. Analysis of the photometric data revealed confident periodicities for 6 objects, with all the lightcurve amplitudes smaller than 0.2 mag, except for 2003 VS₂. Considering all the objects for which reliable lightcurve amplitudes have been reported in the literature (32), the new statistics reveal that 31% of the bodies show variability above 0.15 mag, but only 16% of them display larger amplitudes than 0.4 mag. Here we present a summary of the main results obtained for these objects, and discuss the implications for their basic physical properties.