28 research outputs found
Co-orbital resonance with a migrating proto-giant planet
In this work we pose the possibility that, at an early stage, the migration
of a proto--giant planet caused by the presence of a gaseous circumstellar disk
could explain the continuous feeding of small bodies into its orbit.
Particularly, we study the probability of capture and permanence in co--orbital
resonance of these small bodies, as planets of diverse masses migrate by
interaction with the gaseous disk, and the drag induced by this disk dissipates
energy from these small objects, making capture more likely. Also, we study the
relevance of the circumplanetary disk, a structure formed closely around the
planet where the gas density is enhanced, in the process of capture. It is of
great interest for us to study the capture of small bodies in 1:1 resonance
because it could account for the origin of the Trojan population, which has
been proposed \citep{2011Icar..215..669K} as a mechanism of quasi-satellites
and irregular satellites capture.Comment: This is a pre-copyedited, author-produced PDF of an article accepted
for publication in PSS following peer review; 9 pages, 9 figure
Exploring the orbital evolution of planetary systems
The aim of this paper is to encourage the use of orbital integrators in the classroom to discover and understand the long term dynamical evolution of systems of orbiting bodies. We show how to perform numerical simulations and how to handle output data in order to reveal the dynamical mechanisms that dominate the evolution of arbitrary planetary systems in timescales of millions of years using a simple but efficient numerical integrator. Through some examples we reveal the fundamental properties of planetary systems: the time evolution of the orbital elements, the free and forced modes that drive oscillations in eccentricity and inclination, the fundamental frequencies of the system, the role of the angular momenta, the invariable plane, orbital resonances, and the Kozai-Lidov mechanism. © 2017 European Physical Society
Origin and Sustainability of The Population of Asteroids Captured in the Exterior Resonance 1:2 with Mars
At present, approximately 1500 asteroids are known to evolve inside or
sticked to the exterior 1:2 resonance with Mars at a = 2.418 AU, being (142)
Polana the largest member of this group. The effect of the forced secular modes
superposed to the resonance gives rise to a complex dynamical evolution.
Chaotic diffusion, collisions, close encounters with massive asteroids and
mainly orbital migration due to the Yarkovsky effect generate continuous
captures to and losses from the resonance, with a fraction of asteroids
remaining captured over long time scales and generating a concentration in the
semimajor axis distribution that exceeds by 20% the population of background
asteroids. The Yarkovsky effect induces different dynamics according to the
asteroid size, producing an excess of small asteroids inside the resonance. The
evolution in the resonance generates a signature on the orbits, mainly in
eccentricity, that depends on the time the asteroid remains captured inside the
resonance and on the magnitude of the Yarkovsky effect. The greater the
asteroids, the larger the time they remain captured in the resonance, allowing
greater diffusion in eccentricity and inclination. The resonance generates a
discontinuity and mixing in the space of proper elements producing
misidentification of dynamical family members, mainly for Vesta and Nysa-Polana
families. The half-life of resonant asteroids large enough for not being
affected by the Yarkovsky effect is about 1 Gyr. From the point of view of
taxonomic classes, the resonant population does not differ from the background
population and the excess of small asteroids is confirmed.Comment: Accepted for publication in Icaru
Origin and sustainability of the population of asteroids captured in the exterior resonance 1:2 with Mars
At present, approximately 1500 asteroids are known to evolve inside or sticked to the exterior 1:2 resonance with Mars at a ≃ 2.418 AU, being (142) Polana the largest member of this group. The effect of the forced secular modes superposed to the resonance gives rise to a complex dynamical evolution. Chaotic diffusion, collisions, close encounters with massive asteroids and mainly orbital migration due to the Yarkovsky effect generate continuous captures to and losses from the resonance, with a fraction of asteroids remaining captured over long time scales and generating a concentration in the semimajor axis distribution that exceeds by 20% the population of background asteroids. The Yarkovsky effect induces different dynamics according to the asteroid size, producing an excess of small asteroids inside the resonance. The evolution in the resonance generates a signature on the orbits, mainly in eccentricity, that depends on the time the asteroid remains captured inside the resonance and on the magnitude of the Yarkovsky effect. The greater the asteroids, the larger the time they remain captured in the resonance, allowing greater diffusion in eccentricity and inclination. The resonance generates a discontinuity and mixing in the space of proper elements producing misidentification of dynamical family members, mainly for Vesta and Nysa-Polana families. The half-life of resonant asteroids large enough for not being affected by the Yarkovsky effect is about 1 Gyr. From the point of view of taxonomic classes, the resonant population does not differ from the background population and the excess of small asteroids is confirmed.Fil: Tabaré Gallardo, Carlos. Universidad de la República; UruguayFil: Venturini, Julia. Universidad de la República; UruguayFil: Roig, Fernando Virgilio. Ministério de Ciencia, Tecnologia e Innovacao. Observatorio Nacional; BrasilFil: Gil Hutton, Ricardo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Complejo Astronómico "el Leoncito". Universidad Nacional de Córdoba. Complejo Astronómico ; Argentin
The Relativistic Factor in the Orbital Dynamics of Point Masses
There is a growing population of relativistically relevant minor bodies in
the Solar System and a growing population of massive extrasolar planets with
orbits very close to the central star where relativistic effects should have
some signature. Our purpose is to review how general relativity affects the
orbital dynamics of the planetary systems and to define a suitable relativistic
correction for Solar System orbital studies when only point masses are
considered. Using relativistic formulae for the N body problem suited for a
planetary system given in the literature we present a series of numerical
orbital integrations designed to test the relevance of the effects due to the
general theory of relativity in the case of our Solar System. Comparison
between different algorithms for accounting for the relativistic corrections
are performed. Relativistic effects generated by the Sun or by the central star
are the most relevant ones and produce evident modifications in the secular
dynamics of the inner Solar System. The Kozai mechanism, for example, is
modified due to the relativistic effects on the argument of the perihelion.
Relativistic effects generated by planets instead are of very low relevance but
detectable in numerical simulations