Unit:
Κατεύθυνση ΑστροφυσικήLibrary of the School of Science
Author:
Athanasopoulos Dimitrios
Supervisors info:
Κοσμάς Γαζέα, Λέκτορας, Τμήμα Φυσικής, Εθνικό και Καποδιστριακό Πανεπιστήμιο Αθηνών
Κλεομένης Τσιγάνης, Αναπληρωτής Καθηγητής, Τμήμα Φυσικής, Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης
Marco Delbo, Research Director, Observatoire de la Côte d’Azur
Original Title:
Photometric investigation of primordial asteroids
Translated title:
Photometric investigation of primordial asteroids
Summary:
A small percentage (~25%) of discovered asteroids has been associated with more than 100 known asteroid families. The determination of which asteroids of the remaining population are members of undiscovered families would constrain the original planetesimal population. Such a classification of the asteroids seems to be the key for the understanding of the dynamical and the collisional evolution of the asteroid population and the correlation between of them.
Despite the very valuable information from space missions extremely important data about asteroids are provided by photometric observations from ground-based telescopes. Short term time-series photometry (of the order of several hours or days) reveal the rotational period and the amplitude of changes of brightness in a variety of solar phase angles. Long-term photometry (of the order of several months or years) detects amplitude variations in different apparitions, determines the direction of rotation axes and the sense of rotation and helps to create a 3D model of the asteroid's shape.
In this master thesis, photometric observations have been performed for Main Belt asteroids 2839 Annette (1929 TP), 2768 Gorky (1972 RX3) and 9086 (1995 SA3), members of the so-called "Primordial family", a recently discovered collisional family in the inner Main Belt, that could be as old as the Solar System. The observed lightcurves of the asteroids have been analyzed revealing information about their spin state and shape. These physical properties give insights about their membership and the family evolution.
The findings of this research indicate that 2839 Annette (1929 TP) is a retrograde and suspected Non-Principal Axis (NPA) rotator, 2768 Gorky (1972 RX3) is probably a prograde rotator with low spin pole ecliptic latitude (i.e., β≾30°) and 9086 (1995 SA3) has a possible binary or tumbling nature. These characteristics comprise evidence of a past perturbation to the Primordial family.
This study will potentially lead to a better understanding of the first stages of the evolution of the Solar System, the mechanism at the origin of the formation of the asteroids and the planet formation processes. The asteroid belt provides valuable information for the origin and the evolution of the Solar System, probably more than the information provided by the planets.
Main subject category:
Science
Keywords:
photometry, lightcurve, asteroid, primordial, collisional, family, YORP effect, planetary system, Main Belt, DAMIT Software
Number of references:
258
