Consideration of a Circumsolar Dust Ring in Resonant Lock with the Venus

Abstract

Interplanetary space is filled with dust particles. It has been considered that the dust particles are supplied predominantly by comets and asteroids. Once dust particles are ejected from the parent bodies, they lose their angular momentum by solar radiation pressure, causing the dust grains to slowly spiral inward (Poynting-Robertson effect). As the dust particles move toward the Sun under the influence of Poynting-Robertson effect, they have a chance to encounter planetary resonances forming a local enhancement of dust cloud surrounding the sun (circumsolar resonance ring). The circumsolar resonance ring on the Earth orbit was detected in the zodiacal cloud through observations with infrared space telescopes. There was no definitive evidence other than Earth because of the difficulty in observation from Earth bounded orbit. However, Leinert et al. (2007) suggested that Helios spacecraft might detect the ring structure in 1970s when it passed the orbit of Venus, which motivated the present research. We thus performed a dynamical simulation with the MERCURY6 Integrator to examine whether the circumsolar resonance ring associated with Venus is detectable or not. We considered solar radiation pressure, solar gravity, and planetary perturbations for the simulation. As the result, we found that (i) asteroidal dust particles are preferentially trapped in mean motion resonances of both Venus and Earth, (ii) the Venusian resonance ring definitively formed theoretically but the surface brightness would be 20 % of the Earth resonance ring. Finally, it should be noticed that the Venusian resonance ring has just been detected with a space telescope recently (Jones et al. 2013) as we predicted in this thesis.