#TITLE_ALTERNATIVE#

• Main Author: Fermita (NIM : 103 03 016), Adelia
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/5638
• Institution: Institut Teknologi Bandung

ABSTRACT: <br /> <br /> <br /> <br /> <br /> <br /> The classical evolutionary model (Classical Model, CM) of asteroids is collisional and gravitational perturbations among asteroids in the main belt. The CM suggests frequent collisional events occurred in the main-belt. Catastrophic collisions result in small fragments grouped in asteroids families. The fragments are ejected out from a parent body with their own escape velocities. Then they would be injected into resonances that may transfer them to different regions in the solar system. However, predictions of this model show inconsistencies compared to the recent observational results. The last decade these inconsistencies have been convincingly explained by the non-gravitational effects. There are some variants of non-gravitational effect, and the most appropriate one is the thermal radiation effect. This effect consists of the so called Yarkovsky and YORP effects. Yarkovsky effect occurs when there is a difference between absorption and radiation of sunlight on the surface of asteroid. This effect may change the semimajor axis of asteroid. On the other hand, YORP effect may change the obliquity and spin rates of asteroid, and dominant for asteroids whose shapes are irregular. Orbital evolution tests have been done to show qualitatively the influences of Yarkovsky and YORP effects for km sized asteroids originally located at some regions in the main belt. The integration software, namely swift rmvsy, was run to calculate the evolutionary orbits of the asteroids for 100 Myr taking into account the typical physical parameters. Results of the integrations show three delivery processes of asteroids from the main belt (to the near Earth region, encountering the planets, or ejected out from the solar system) with the help of resonances and planetary perturbations. In addition, some of them show small drift on semimajor axis along the entire integration. In general, Yarkovsky effects play as an important role in the early evolution that guides the asteroids to track different evolutionary paths than that of without involving the Yarkovsky effects.