我同時也使用Mercury軟體來分析木族彗星的動力學特徵。結合觀測資料與軌道數值模擬，由於彗星核心保存的揮發性物質是有限的，我們可以建立起彗星活動特性與動力學時間尺度兩者之間的關聯。論文中詳細的討論了造成彗星活動如此多變的可能原因。;I developed a systematic method to analyze the snapshot images from sky survey projects such as the Pan-STARRS 1 (PS1) and Palomar Transient Factory (PTF) on all the numbered Jupiter Family Comets (JFCs). There are three objectives for my image processing pipeline to handling the five years survey data: to find out images that contains target of interest; to identify the signature of coma activity; and to measure the level of outgassing activity. Given that cometary activities are generally triggered by the sublimation of water ice, I introduce the water ice snowline at 3 au as an indicator for the comet classification. All comets analyzed in this work are classified into four groups based on its behaviors: regular active comets with coma activities within the snowline only, abnormal active comets with coma activities detected beyond the snowline, low active comets that are always inactive and appear as point-like sources, and undetectable comets.
I also use the Mercury integrator to study dynamic features of JFCs by numerical methods. Combining the observational and numerical results, a connection between active behaviors and dynamics has been established: due to the limited amount of volatiles in the cometary nuclei, dynamic age roughly reflects the appearance of cometary activity. A detail discussion is given in this thesis for possible explanations of various cometary activities.
