VACHIER , Frédéric

We aim at studying the dynamical system of the asteroid (379) Huenna and its satellite, for which a discrepancy between its predicted and observed position was reported by DeMeo et al. (2011, Icarus, 212). We compile all the available images of the system acquired with large ground-based telescopes equipped with adaptive-optics fed camera....

International audience

The TAROTs (Télescopes à Action Rapide pour les Objets Transitoires; Rapid Action Telescopes for Transient Objects) are two fully robotic observatories designed to observe the early transient optical counterpart of gamma-ray bursts (GRBs). As their occurrence is rare, we also use TAROT to observe various other celestial objects: RR Lyrae stars,...

The Institut de mecanique celeste et de calcul des ephemerides (IMCCE, Paris Observatory) is willing to provide information on Solar System objects to the Astronomical Virtual Observatory. The first step is the interconnection of IMCCE ephemerides servers with the Vizier and Aladin tools of the Centre de donnees astronomiques de Strasbourg...

The Swift burst GRB 110205A was a very bright burst visible in the Northern hemisphere. GRB 110205A was intrinsically long and very energetic and it occurred in a low-density interstellar medium environment, leading to delayed afterglow emission and a clear temporal separation of the main emitting components: prompt emission, reverse shock, and...

Mutual event observations between the two components of 90 Antiope were carried out in 2007-2008. The pole position was refined to λ = 199.5 ± 0.5° and β = 39.8 ± 5° in J2000 ecliptic coordinates, leaving intact the physical solution for the components, assimilated to two perfect Roche ellipsoids, and derived after the 2005 mutual event season...

On 5-6 June 2012, Venus will be transiting the Sun for the last time in this century. This unique opportunity, besides offering the opportunity of investigating the mesosphere of the planet, also provides a significant nearby analog of exoplanet transits. Several studies using the transmission spectroscopy technique have provided significant...