아리랑 위성 1호 (KOMPSAT-1) 궤도 변화와 우주환경 변화 비교

다국어 초록 (Multilingual Abstract)

In this paper, we examine the drag effect of the Korea Multi-Purpose Satellite-1(KOMPSAT-1) during extreme solar and geomagnetic activity. It is well known that there exists serious satellite drag when the space environment is suddenly changed during extreme solar and geomagnetic activity caused by big flares and/or fast halo coronal mass ejections(CMEs). According to Cho et al.(2004), the KOMPSAT-1, as a Low-Earth Orbit(LEO) satellite, experienced serious errors in its 3-days orbit prediction due to extreme solar and geomagentic activity in October and November, 2003. There are two major mechanisms to induce satellite drags: the heating by solar EUV radiation (characterized by F10.7), and the heating by joule heating via particle precipitation during geomagnetic storms (characterized by Dst and Polar Cap index). In order to examine these effects, we select five events dominated by the radiation effect and/or the particle effect. In addition, we compared the density from drag acceleration equation with that based on the MSISE-90 empirical atmospheric model. The major results can be summarized as follows. (1) The satellite drag, represented by drag acceleration, started simultaneously with the increase of solar EUV radiation such as solar flares and then has the best correlation with the 1 day delayed F10.7. (2) The variations of drag and Dst index have similar patterns when geomagnetic storms are dominant. (3) The comparison of two derived densities (drag data and model) shows that the empirical atmospheric density model such as MSISE-90 does not well account for the density variation during the extreme activity, as considered in this study.

목차 (Table of Contents)

• 1 장. 서론 = 1
• 1. 1 연구 배경 = 1
• 1. 2 우주환경이 위성체에 미치는 영향 = 2
• 1. 3 고층 대기의 변화 = 4
• 1. 4 위성체에 대한 대기 저항력 (Air Drag force) = 6
• 1. 5 연구 동기 = 7
• 2 장. 자료 및 모델 = 9
• 2. 1 극심한 우주환경 사건 (event) 선정 = 9
• 2. 1. 1 복사에 의한 효과 = 9
• 2. 1. 2 물질에 의한 효과 = 10
• 2. 2 아리랑 위성 1호의 궤도 변화 자료 = 11
• 2. 2. 1 대기 저항 가속도 (Air Drag acceleration) = 12
• 2. 2. 2 장반경 변화율 (Semi-Major axis rate) = 14
• 2. 3 MSIS 모델 = 17
• 3 장. 자료 분석 및 비교 = 19
• 3. 1 우주환경 지수 = 19
• 3. 1. 1 태양활동 지수 : F10.7 = 19
• 3. 1. 2 지자기활동 지수 : Kp 와 ap, Dst, PC = 20
• 3. 2 아리랑 위성 1호의 궤도 변화와 비교 = 24
• 3. 2. 1 2001년 12월 28일 = 24
• 3. 2. 2 2002년 7월 20일 = 26
• 3. 2. 3 2002년 8월 30일 = 28
• 3. 2. 4 2001년 3월 28일 = 30
• 3. 2. 5 2001년 11월 21일 = 33
• 3. 3 모델과 비교 = 34
• 4 장. 결과 및 토론 = 37
• 참고문헌 = 40
• Abstract = 42
• 감사의 글