Discovery of the first olivine-dominated A-type asteroid family - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Astronomy and Astrophysics - A&A Année : 2024

Discovery of the first olivine-dominated A-type asteroid family

M. Galinier
  • Fonction : Auteur correspondant
M. Delbo
  • Fonction : Auteur
C. Avdellidou
  • Fonction : Auteur
L. Galluccio
  • Fonction : Auteur

Résumé

The classical theory of differentiation states that due to the heat generated by the decay of radioactive elements, some asteroids form an iron core, an olivine-rich mantle, and a crust. The collisional breakup of these differentiated bodies is expected to lead to exposed mantle fragments, creating families of newly-formed asteroids. Among these new objects, some are expected to show an olivine-rich composition in spectroscopic observations. However, several years of spectrophotometric surveys have led to the conclusion that olivine-rich asteroids are rare in the asteroid main belt, and no significant concentration of olivine-rich bodies in any asteroid family has been detected to date. Using ESA’s Gaia DR3 reflectance spectra, we show that the family (36256) 1999 XT17 presents a prominence of objects that are likely to present an olivine-rich composition (A-type spectroscopic class). If S-complex asteroids as the second most prominent spectroscopic class in the family are real family members, then arguably the 1999 XT17 family has originated from the break-up of a partially differentiated parent body. Alternatively, if the S-complex asteroids are interlopers, then the 1999 XT17 family could have originated from the breakup of an olivine-rich body. This body could have been part of the mantle of a differentiated planetesimal, which may have broken up in a different region of the Solar System, and one of its fragments (i.e. the parent body of the 1999 XT17 family) could have been dynamically implanted in the main belt.
Fichier principal
Vignette du fichier
aa49057-23.pdf (1.11 Mo) Télécharger le fichier
Origine : Publication financée par une institution

Dates et versions

hal-04484758 , version 1 (29-02-2024)

Identifiants

Citer

M. Galinier, M. Delbo, C. Avdellidou, L. Galluccio. Discovery of the first olivine-dominated A-type asteroid family. Astronomy and Astrophysics - A&A, 2024, 683, pp.L3. ⟨10.1051/0004-6361/202349057⟩. ⟨hal-04484758⟩
4 Consultations
1 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More