Trojan asteroids and the early evolution of the solar system

Lykawka, Patryk S. and Horner, J. and Jones, B. and Mukai, T. (2010) Trojan asteroids and the early evolution of the solar system. In: 42nd DPS Meeting of the American Astronomical Society , 4-5 Oct 2010, Pasadena, CA. United States.

[img]
Preview
Text (Published Version)
Lykawka_etal_42DPS_PV.pdf

Download (20Kb) | Preview

Abstract

Trojan asteroids can be used to constrain Trojan formation mechanisms, giant planet formation/migration and the orbital structure in the asteroid and Kuiper belts. We performed numerical simulations totaling a few million massless objects under the gravitational influence of the four giant planets. Firstly, we looked at the dynamics of primordial (local) Neptune Trojans placed at the L4/L5 Lagrange points in compact planetary systems prior to planet migration, over 10Myr. We also investigated the evolution of local Neptune Trojans and captured Trojans from a planetesimal disk for all giant planets during planet migration. The orbits were integrated for several Myr, after which the giant planets acquired their current orbits. The orbits of representative final populations were also integrated over Gyr. Overall, the great majority of plausible pre-migration planetary systems resulted in severe levels of depletion of the Neptunian Trojan clouds prior to planet migration. In particular, substantial Trojan losses occurred when Uranus and Neptune were placed near their mutual 2:3 or 3:4 MMR and within 18 AU. Neptune Trojan populations were obtained at the end of the migrating scenarios, composed of remaining local and captured Trojan asteroids. In addition to Neptune, the other three giant planets were also able to capture and retain a significant population of Trojan objects from the disk after planet migration. Finally, the distributions of these objects and their resonant properties were obtained after Gyr. In general, captured Trojans yielded a wide range of eccentricities and inclinations, while local Trojans survived with colder orbital conditions. However, the bulk of captured objects decay over Gyr, providing an important source of new objects on unstable orbits (the Centaurs). Our results suggest the bulk of observed Jovian and Neptunian Trojan populations were captured from the primordial planetesimal disk during planet migration, but their high-i component (>20°) remain unexplained so far.


Statistics for USQ ePrint 25561
Statistics for this ePrint Item
Item Type: Conference or Workshop Item (Commonwealth Reporting Category E) (Poster)
Refereed: No
Item Status: Live Archive
Additional Information: This publication is copyright. It may be reproduced in whole or in part for the purposes of study, research, or review, but is subject to the inclusion of an acknowledgment of the source. Presentation no: 40.15.
Faculty / Department / School: Historic - Faculty of Engineering and Surveying - No Department
Date Deposited: 23 Jul 2014 01:48
Last Modified: 23 Jul 2014 23:23
Uncontrolled Keywords: solar system formation; planets; asteroids
Fields of Research : 02 Physical Sciences > 0201 Astronomical and Space Sciences > 020105 General Relativity and Gravitational Waves
02 Physical Sciences > 0201 Astronomical and Space Sciences > 020108 Planetary Science (excl. Extraterrestrial Geology)
02 Physical Sciences > 0201 Astronomical and Space Sciences > 020101 Astrobiology
Socio-Economic Objective: E Expanding Knowledge > 97 Expanding Knowledge > 970102 Expanding Knowledge in the Physical Sciences
URI: http://eprints.usq.edu.au/id/eprint/25561

Actions (login required)

View Item Archive Repository Staff Only