A new non-convex model of the binary asteroid 90 Antiope obtained with the SAGE modelling technique

Abstract

We present a new non-convex model of the 90 Antiope binary asteroid, derived with a modified version of the SAGE (Shaping Asteroids with Genetic Evolution) method using disk-integrated photometry only. A new variant of the SAGE algorithm capable of deriving models of binary systems is described. The model of 90 Antiope confirms the system's pole solution ($\lambda =199^{\circ }$, $\beta =38^{\circ }$, $\sigma =\pm 5^{\circ }$) and the orbital period ($16.505046\pm 0.000005$ h). A comparison between the stellar occultation chords obtained during the 2011 occultation and the projected shape solution has been used to scale the model. The resulting scaled model allowed us to obtain the equivalent radii ($R_1=40.4\pm 0.9$ km and $R_2=40.2\pm 0.9$ km) and the distance between the two system components ($176\pm 4$ km), leading to a total system mass of ($9.14\pm 0.62$)$\cdot 10^{17}$ kg. The non-convex shape description of the components permitted a refined calculation of the components' volumes, leading to a density estimation of $1.67\pm 0.23$ g cm${}^{-3}$. The intermediate-scale features of the model may also offer new clues on the components' origin and evolution.

References in corpus (2)

• Multiple Asteroid Systems: Dimensions and Thermal Properties from Spitzer Space Telescope and Ground-Based Observations
• Angular Momemtum of Binary Asteroids: Implication for their possible origin

Cited by in corpus (8)

• Asteroid Systems: Binaries, Triples, and Pairs
• Asteroid Models from Multiple Data Sources
• Spin states of asteroids in the Eos collisional family
• Photometric survey, modelling, and scaling of long-period and low-amplitude asteroids
• Small Bodies Near and Far (SBNAF): a benchmark study on physical and thermal properties of small bodies in the Solar System
• Thermal properties of large main-belt asteroids observed by Herschel PACS
• Shape models and physical properties of asteroids
• A new non-convex model of the binary asteroid (809) Lundia obtained with the SAGE modelling technique