The Surface Composition and Temperature of Asteroid 21 Lutetia As Observed by Rosetta/VIRTIS

Coradini A, Capaccioni F, Erard S, Arnold G, De Sanctis MC, Filacchione G, Tosi F, Barucci MA, Capria MT, Ammannito E, Grassi D, Piccioni G, Giuppi S, Bellucci G, Benkhoff J, Bibring JP, Blanco A, Blecka M, Bockelee-Morvan D, Carraro F, Carlson R, Carsenty U, Cerroni P, Colangeli L, Combes M, Combi M, Crovisier J, Drossart P, Encrenaz ET, Federico C, Fink U, Fonti S, Giacomini L, Ip WH, Jaumann R, Kuehrt E, Langevin Y, Magni G, McCord T, Mennella V, Mottola S, Neukum G, Orofino V, Palumbo P, Schade U, Schmitt B, Taylor F, Tiphene D, Tozzi G

Research article (journal) | Peer reviewed

Abstract

The Visible, InfraRed, and Thermal Imaging Spectrometer (VIRTIS) on Rosetta obtained hyperspectral images, spectral reflectance maps, and temperature maps of the asteroid 21 Lutetia. No absorption features, of either silicates or hydrated minerals, have been detected across the observed area in the spectral range from 0.4 to 3.5 micrometers. The surface temperature reaches a maximum value of 245 kelvin and correlates well with topographic features. The thermal inertia is in the range from 20 to 30 joules meter-2 kelvin-1 second-0.5, comparable to a lunarlike powdery regolith. Spectral signatures of surface alteration, resulting from space weathering, seem to be missing. Lutetia is likely a remnant of the primordial planetesimal population, unaltered by differentiation processes and composed of chondritic materials of enstatitic or carbonaceous origin, dominated by iron-poor minerals that have not suffered aqueous alteration.

Details about the publication

JournalScience (Sci)
Volume334
Issue6055
Page range492-494
StatusPublished
Release year2011
Language in which the publication is writtenEnglish
DOI10.1126/science.1204062

Authors from the University of Münster

Arnold, Gabriele
Institute for Planetology