EDP Sciences
Free access
Volume 417, Number 3, April III 2004
Page(s) 1159 - 1164
Section Planets and planetary systems
DOI http://dx.doi.org/10.1051/0004-6361:20035658

A&A 417, 1159-1164 (2004)
DOI: 10.1051/0004-6361:20035658

Post-perihelion observations of comet 1P/Halley

V: r $_\mathsf{h}$ = 28.1 AU
O. R. Hainaut1, A. Delsanti2, K. J. Meech3 and R. M. West4

1  European Southern Observatory, Casilla 19001, Santiago 19, Chile
2  Observatoire de Paris-Meudon - LESIA, 5 Place Jules Janssen, 92195 Meudon Cedex, France
    e-mail: Audrey.Delsanti@obspm.fr
3  Institute for Astronomy, University of Hawai`i, 2680 Woodlawn Drive, Honolulu, HI 96822, USA
    e-mail: meech@ifa.hawaii.edu
4  European Southern Observatory, Karl-Schwarzschild-Straße 2, 85748 Garching-bei-München, Germany
    e-mail: rwest@eso.org

(Received 11 November 2003 / Accepted 18 December 2003 )

Deep CCD observations have been performed simultaneously with the three 8.2 m Very Large Telescopes at Paranal, in the direction of comet 1P/Halley, on March 6-8, 2003. The comet, at heliocentric distance r=28.1 AU, was convincingly detected (at  S/N=8) on a composite of 32 284 s exposure, as a point-source located 1.4 '' from the expected position. The object is also visible (at the S/N=3-5 level) on independent per-night or per-instrument composites, confirming the reality of the object, and the match of the observed motion over 3 consecutive nights with the predicted motion of 1P/Halley guarantees that this cannot be another Solar System object. The magnitude of the object, R=28.22  $\pm$ 0.13, is compatible with the average cross-section of the bare nucleus.

Key words: comets: individual: 1P/Halley

Offprint request: O. Hainaut, ohainaut@eso.org

© ESO 2004