| 摘要: | 地球的中、高層大氣層與電離層有密切的關聯與耦合現象，兩者的結構與變遷對無線通 訊、低軌道人造衛星空氣阻力、以及日地系統整體的連接有重要的影響。中性大氣的風場、溫場、 以及電離層的電漿濃度、電漿溫度、飄移速度、化學組成皆是了解、監測中高層大氣與電離層的 重要觀測參數。人造衛星廣大的觀測範圍是提供這些觀測數據的絕佳平台，但是現有觀測高層大 氣與電離層的大型衛星任務酬載所能提供的數據高度與地方時間分布仍然有限。高層大氣科學界 因此對以廉價小衛星為平台，搭載大氣、電離層探測酬載的小衛星群任務有所需求。 立方體衛星（CubeSat）是過去十年開始廣泛使用的奈米衛星（nanosatellite） 標準形式， 體積由一個或多個邊長 10 公分的立方體組成。CubeSat 雖然起初是為了大學生實習系統設計、 組裝的教育需求而產生，該衛星規格現在已廣泛受學界、業界運用執行多元的衛星任務，其中 CubeSat 科學任務已成為日地物理、太空與大氣科學界熱門的觀測平台。本五年計劃將與有多年 衛星、酬載開發經驗的美國科羅拉多大學（University of Colorado，簡稱CU）大氣與太空物理實 驗室（Laboratory for Atmospheric and Space Physics，簡稱 LASP）進行國際合作，分別開發有能 力承載現有大氣、電離層觀測酬載的 CubeSat 衛星本體、任務、並於發射後進行任務作業及資料 分析，以觀測高層大氣與電離層結構及耦合現象。 本計劃CubeSat 科學酬載已訂為 CU LASP 將提供的 Doppler Wind and Temperature Sounder (DWTS) 以及國立中央大學所開發的 Advanced Ionosphere Probe (AIP)。DWTS 為新開發 的大氣輻射儀，有能力同步觀測 20 – 250 km 的中性大氣風場及溫場，並適合以CubeSat 平台進 行首次的作業測試。AIP 為一枚小型多功能的電離層原地觀測儀，可提供電離層電子濃度、電漿 溫度、飄移速度、化學組成、等參數。AIP 體積、質量與 CubeSat 大小相輔，另外亦為福衛5 號科學酬載，成熟度極高。本計劃將分別為符合 DWTS 及 AIP 需求的 CubeSat 衛星主體及任 務進行設計。搭載這兩個酬載的 CubeSat 將有能力大輔擴大高層大氣界隊中、高層大氣及電離層 的觀測能力。 本計劃後續將針對完成的 DWTS 衛星本體設計進行組裝及測試作業，並由本團隊負責該 任務衛星主體工程體組裝。本計劃主持人及學校已與 CU 簽署小衛星開發 MOU，並為 CU LASP 所推動的 InSPiRE （International Satellite Program in Research and Education） 國際小衛星合作計 畫的發起單位之一。CU LASP 已與印度太空研究組織（Indian Space Research Organization，簡稱 ISRO）達成 2018 年發射 DWTS 任務 CubeSat 的協議。本計劃一方面可滿足高層大氣科學界 對大氣、電離層觀測的需求，另外可大幅提昇我國大氣、太空科學界運用 CubeSat 進行科學任務 的設計及作業能力，並與參加InSPiRE 計畫的多國學術研究單位建立合作關係。 ;The Earth’s neutral atmosphere and ionosphere are a coupled system, whose structure and variability have important implications for wireless communications, Low Earth Orbit satellite drag, as well as understanding the Sun-Earth connection. In order to better understand atmosphere-ionosphere coupling processes, global scale observations of neutral atmospheric winds, temperatures, as well as ionospheric electron densities, temperatures, drifts, and composition are required. The scale of such observations exceeds the spatial and local time coverage currently provided by existing satellite missions. This need therefore exists for constellations of small spacecraft with scientific payloads capable of providing such observations. CubeSats are a standardized class of nanosatellites with volume in multiples of 10 x 10 x 10 cm cubes. Although initially developed for educational purposes, CubeSats have grown to become an important platform for atmospheric and space science payloads. In this proposal, we detail a 5-year CubeSat system development and operations program, in collaboration with the University of Colorado (CU) Laboratory for Atmospheric and Space Physics (LASP). The first portion of this project will to complete preliminary designs for two CubeSat satellite busses respectively suitable for two upper atmospheric science missions. The payload for the first mission is the Doppler Wind and Temperature Sounder (DWTS), a newly developed radiometer provided by CU LASP, capable of measuring atmospheric winds and temperatures from the stratosphere through the thermosphere, and well suited for operational testing on a CubeSat platform. The second payload is the Advanced Ionosphere Probe (AIP), a multifunction in-situ plasma sensor developed in Taiwan at National Central University, with flight heritage from FORMOSAT-5. CubeSat missions carrying DWTS and AIP will allow for unprecedented observations of both neutral middle and upper atmospheric winds and temperatures, as well as ionospheric composition, plasma temperatures, and drift velocities. This will significantly enhance our understanding of the vertical coupling of the atmosphere-ionosphere system via atmospheric waves and tides. The second portion of this project will be the fabrication, testing, and launch of the DWTS CubeSat. As part of LASP’s multinational InSPiRE (International Satellite Program in Research and Education) program, a launch opportunity has already been secured for the DWTS mission via the Indian Space Research Organization (ISRO) in 2018. The Taiwan team will be responsible for the fabrication of the engineering model satellite bus for this mission. Following launch, this project will transition to supporting mission operations, including telemetry downlink, data processing, and analysis. This project will significantly enhance the design and operational capability of the atmospheric and space science community in Taiwan in utilizing CubeSats as a tool for scientific observations, while also providing an observational dataset crucial for understanding atmosphere-ionosphere coupling. The multinational collaboration supported by this project will also serve as a foundation for future space science collaborations between the institutions involved, while also enhancing space science, engineering, and operations experience in Taiwan. |
