Volume 483, Number 2, May IV 2008
|Page(s)||L17 - L20|
|Published online||08 April 2008|
Letter to the Editor
Physical and dynamical properties of (12929) 1999 TZ1 suggest that it is a Trojan
LESIA-Observatoire de Paris, 5 place J. Janssen, 92195 Meudon, France e-mail: email@example.com
2 CSIC-Instituto de Astrofisíca de Andalusía, Granada, Spain
3 Observatoire de la Côte d'Azur, Nice, France
Accepted: 27 March 2008
Context. Small body (12929) 1999 TZ1 is listed by the Minor Planet Center (MPC) as a Centaur. However, its location close to the Lagrangian point L5 of Jupiter is typical of a Trojan object with large inclination.
Aims. The aim of this work is to provide a global physical and dynamical characterization of this object and to reassess its classification.
Methods. We obtained multi-wavelength observations with IRTF (Hawaii), OSN and IRAM-30 m (Spain), and performed a dynamical simulation of the evolution of its orbital parameters.
Results. Visible photometry monitoring shows a rotation curve with a period (if considered double-peaked) of 10.4 ± 0.1 h and an absolute R magnitude HR = 9.792 ± 0.025. Near-IR spectroscopy indicates a featureless reflectance spectra, with a low spectral slope of 7.2 ± 0.11%/100 nm. Thermal observations at 250 GHz provide a 4.5σ detection with a flux of 1.22 ± 0.27 mJy. The combination of the visible and millimeter datasets, assuming a standard thermal model, leads to a geometric albedo pv = and a mean diameter of 51.5 ± 5 km.
Conclusions. The low albedo and spectral slope measured are typical of Jupiter's Trojans, but cannot exclude a Centaur nature. However, the dynamical lifetime of the object was estimated to be longer than 1 Gy, which is unlikely for a Centaur and suggests that (12929) 1999 TZ1 is a Trojan asteroid.
Key words: minor planets, asteroids / radio continuum: solar system / infrared: solar system / celestial mechanics
© ESO, 2008
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.