EDP Sciences
Free access
Volume 430, Number 1, January IV 2005
Page(s) 313 - 317
Section Planets and planetary systems
DOI http://dx.doi.org/10.1051/0004-6361:20041505

A&A 430, 313-317 (2005)
DOI: 10.1051/0004-6361:20041505

Asteroid target selection for the new Rosetta mission baseline

21 Lutetia and 2867 Steins
M. A. Barucci1, M. Fulchignoni1, S. Fornasier2, E. Dotto3, P. Vernazza1, M. Birlan4, R. P. Binzel5, J. Carvano1, F. Merlin1, C. Barbieri2 and I. Belskaya6

1  LESIA, Observatoire de Paris, 92195 Meudon Principal Cedex, France
    e-mail: antonella.barucci@obspm.fr
2  Astronomy Department, Padova University, Vicolo dell'Osservatorio 2, 35122 Padova, Italy
3  INAF - Osservatorio Astronomico di Roma, via Frascati 33, 00040 Monte Porzio Catone, Roma, Italy
4  IMCCE, Observatoire de Paris, 75014 Paris, France
5  Dep. of Earth, Atmosph. and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
6  Astronomical Observatory of Kharkiv National University, Ukrania

(Received 22 June 2004 / Accepted 18 September 2004)

The new Rosetta mission baseline to the comet 67P/Churyumov-Gerasimenko includes two asteroid fly-bys. To help in target selection we studied all the candidates of all the possible scenarios. Observations have been carried out at ESO-NTT (La Silla, Chile), TNG (Canaries), and NASA-IRTF (Hawaii) telescopes, in order to determine the taxonomy of all the candidates. The asteroid targets were chosen after the spacecraft interplanetary orbit insertion manoeuvre, when the available total amount of $\Delta V$ was known. On the basis of our analysis and the available of $\Delta V$, we recommended to the ESA Science Working Group the asteroids 21 Lutetia and 2867 Steins as targets for the Rosetta mission. The nature of Lutetia is still controversial. Lutetia's spectral properties may be consistent with a composition similar to carbonaceous chondrite meteorites. The spectral properties of Steins suggest a more extensive thermal history. Steins may have a composition similar to relatively rare enstatite chondrite/achondrite meteorites.

Key words: minor planets, asteroids -- techniques: spectroscopic

© ESO 2005