Matching asteroid population characteristics with a model constructed from the YORP-induced rotational fission hypothesis

Abstract

From the results of a comprehensive asteroid population evolution model, we conclude that the YORP-induced rotational fission hypothesis can be consistent with the observed population statistics of small asteroids in the main belt including binaries and contact binaries. The foundation of this model is the asteroid rotation model of Marzari et al. (2011), which incorporates both the YORP effect and collisional evolution. This work adds to that model the rotational fission hypothesis and the binary evolution model of Jacobson & Scheeres (2011). The asteroid population evolution model is highly constrained by these and other previous works, and therefore it has only two significant free parameters: the ratio of low to high mass ratio binaries formed after rotational fission events and the mean strength of the binary YORP (BYORP) effect. We successfully reproduce characteristic statistics of the small asteroid population: the binary fraction, the fast binary fraction, steady-state mass ratio fraction and the contact binary fraction. We find that in order for the model to best match observations, rotational fission produces high mass ratio ($>0.2$) binary components with four to eight times the frequency as low mass ratio ($<0.2$) components, where the mass ratio is the mass of the secondary component divided by the mass of the primary component. This is consistent with post-rotational fission binary system mass ratio being drawn from either a flat or a positive and shallow distribution, since the high mass ratio bin is four times the size of the low mass ratio bin; this is in contrast to the observed steady-state binary mass ratio, which has a negative and steep distribution. This can be understood in the context of the BYORP-tidal equilibrium hypothesis, which predicts that low mass ratio binaries survive for a significantly longer period of time than high mass ratio systems.

References in corpus (21)

• Solar System Objects Observed in the SDSS Commissioning Data
• Dynamics of rotationally fissioned asteroids: Source of observed small asteroid systems
• Formation of asteroid pairs by rotational fission
• Tidal Evolution of Rubble Piles
• Extreme Sensitivity of the YORP Effect to Small-Scale Topography
• Disintegrating Asteroid P/2013 R3
• The Influence of Rough Surface Thermal-Infrared Beaming on the Yarkovsky and YORP Effects
• Long-term Stable Equilibria for Synchronous Binary Asteroids
• Internal Structure of Asteroids Having Surface Shedding due to Rotational Instability
• Tangential component of the YORP effect
• A 3-dimensional model of tangential YORP
• Binary Asteroid Systems: Tidal End States and Estimates of Material Properties
• Tidal Evolution of Asteroidal Binaries. Ruled by Viscosity. Ignorant of Rigidity
• The binary near-Earth asteroid (175706) 1996 FG3 - An observational constraint on its orbital evolution
• Near-Earth Binaries and Triples: Origin and Evolution of Spin-Orbital Properties
• Effect of rotational disruption on the size-frequency distribution of the Main Belt asteroid population
• Near-Earth Asteroid Satellite Spins Under Spin-Orbit Coupling
• The Formation of the Wide Asynchronous Binary Asteroid Population
• Binary Asteroid Encounters with Terrestrial Planets: Timescales and Effects
• Small asteroid system evolution
• Multiple origins of asteroid pairs

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• Direct $N$-body simulations of satellite formation around small asteroids: insights from DART's encounter with the Didymos system
• Dynamical evolution of near-Earth asteroid 1991 VG
• Non-principal axis rotation in binary asteroid systems and how it weakens the BYORP effect
• Dancing with Venus in the shadow of the Earth: a pair of genetically related near-Earth asteroids trapped in a mean-motion resonance
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• Photometry and Polarimetry of 2010 XC${}_{15}$: Observational Confirmation of E-type Near-Earth Asteroid Pair
• Asteroid 2017 FZ2 et al.: signs of recent mass-shedding from YORP?
• A semi-analytical thermal model for craters with application to the crater-induced YORP effect
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