Asteroids, , Meteors (2008) 8111.pdf

SPECTRAL FEATURES OF 21 , TARGET OF MISSION.

M. Lazzarin1, S. Marchi2, L. Moroz3 and S. Magrin4

1Dipartimento di astronomia, Vicolo dell’Osservatorio 3, 35122 Padova-Italy. E-mail: [email protected] 2Dipartimento di astronomia, Vicolo dell’Osservatorio 3, 35122 Padova-Italy. E-mail: [email protected] 3 German Aerospace Center (DLR), Institute of Planetary Research, Rutherfordstr. 2, D-12489 Berlin, Germany. E-mail: [email protected] 4Dipartimento di astronomia, Vicolo dell’Osservatorio 3, 35122 Padova-Italy. E-mail: [email protected]

The International Rosetta Mission, success- In particular, we investigated the spectral re- fully launched on March 2nd 2004, will en- gion where these bands were detected by us- counter 67P/Churyumov- ing a higher spectral resolution. We con- Gerasimenko, the principal target of the firm a broad complex feature between 0.45 mission, in 2014. During its long journey and 0.55 micron and two narrower features Rosetta will fly-by also two : 2867 around 0.47 and 0.52 micron which possible Steins (September 2008) at a distance of origin will be discussed. about 1700 km and at a relatively low speed A more precise knowledge of the sur- of about 9 kilometers per second and 21 Lu- face composition of Lutetia is particularly tetia (July 2010) at about 3000 km at a speed important for the definition of the observa- of 15 kilometers per second. tional strategy of the Rosetta mission. Rosetta will try to answer to the main ques- tions related to the origin and evolution of the as minor bodies contains the record of the chemical, physical and dynami- cal primordial processes of the formation of our planetary system. In this work we present the analysis of two visible spectra of Lutetia taken at NTT-ESO, Chile, in order to confirm the presence of absorption bands previously determined on other spectra of the (Lazzarin et al., A&A, 2004).