ИСТИНА

An increased attention to asteroid (21) Lutetia arouse after it was announced as an object of the Rosetta space mission of ESA. Due to its peculiar characteristics, Lutetia is one of the most attractive objects for examination within the framework of the mission. Then preliminary investigations of the asteroid with ground-based astronomical methods are of great interest. We have discovered considerable variations in the continuum slope and shape of the visible-range reflectance spectra of the asteroid with rotation in November 2004 (4/5, 5/6 and 7/8) and March 2006 (3/4). Unusual behavior the spectral data obtained in November 2004 led us to a suggestion that Lutetia is a binary object of a complex C-S-M-type [1]. On the other hand, some of the asteroid reflectance spectra obtained in March 2006 may be interpreted as similar to those of carbonaceous chondritic meteorites. The observed variations in Lutetia’s reflectance spectra are probably caused by changes in content of the surface matter with rotation. In our opinion, the asteroid surface may incorporate very different materials from high-temperature silicates and/or Fe-Ni-metals to phyllosilicates. References: [1] Busarev V.V. et al. (2007) LPS XXXVIII, Abstract #1016.