Asteroid 21 Lutetia: Low Mass, High Density

• DOI: 10.1126/science.1209389
• Publication Date: 2011-10-27T18:57:18Z
• Authors: M. Pätzold; T. P. Andert; S. W. Asmar; J. D. Anderson; J.-P. Barriot; M. K. Bird; B. Häusler; M. Hahn; S. Tellmann; H. Sierks; P. Lamy; B. P. Weiss
• Keywords: Ephemeris

Asteroid 21 Lutetia was approached by the Rosetta spacecraft on 10 July 2010. The additional Doppler shift of radio signals imposed Lutetia's gravitational perturbation flyby trajectory were used to determine mass asteroid. Calibrating and correcting for all contributions not associated with Lutetia, a least-squares fit residual frequency observations from 4 hours before 6 after closest approach yields (1.700 ± 0.017) × 10(18) kilograms. Using volume model determined Optical, Spectroscopic, Infrared Remote Imaging System (OSIRIS) camera, bulk density, an important parameter clues its composition interior, is (3.4 0.3) 10(3) kilograms per cubic meter.