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The Institute of Space and Astronautical Science (ISAS) of Japan Aerospace Exploration Agency (JAXA) is studying a new magnetic sail propulsion system, called MagSail since 2002. A MagSail travels interplanetary space by capturing the energy of the solar wind. A MagSail realizes analogous interactions between the solar wind and an artificial magnetic field produced around a spacecraft, to obtain a force in the direction of the solar wind. In order to demonstrate the momentum transfer process of the magnetic sail, we have started a preliminary experiment. In the experimental studies, some strong interactions between the high-density (10(exp 19)/cu m) and high velocity (17 km/s) plasma flow and an artificial magnetic field of about 1 T was observed. Now, we are designing and manufacturing an experimental simulator of the magnetic sail propulsion system. Especially, development of a solar wind simulator will be a key issue for the MagSail experiments. We selected an MPD arcjet device to be the solar wind simulator. And a new twelve L-C ladder Pulse Forming Network (PFN) is also now in manufacturing and testing. In this report, a development status of the MPD solar wind simulator for the MagSail experiment is described and some experimental results are reported., 資料番号: AA0049054024, レポート番号: JAXA-SP-05-008

The fatal anomaly of the Advanced Earth Observing Satellite-2 (ADEOS-2) on the polar earth orbit of 803 km altitude, that was due to an electric power loss from 6 kW to 1 kW, occurred off the coast of Peru from 16:12 to 16:16 UT on 24 October, 2003. It was considered to be caused by the short/open of the electronic cables in the harness connected the solar paddle and the satellite body. That had been probably triggered by electrostatic charging and subsequent discharging of the electronically floating Multi-Layer Insulation (MLI) blanket of the harness by the energetic auroral electron flux when the ADEOS-2 was passing through the northern aurora oval just before the anomaly. Measurements of the onboard energetic charged particle detector were not fully available around the anomaly due to the data transmission schedule. However the NOAA-17 satellite, that was almost 30 km just above the ADEOS-2, observed an extraordinary enhancement of the energetic electron flux at the nightside aurora oval. The total energetic electron flux (larger than 30 keV) is calculated to be 2.94 x 10(exp 10) (particles/sq cm). This total flux is supposed to be enough to charge the floating MLI blanket deeply and induce discharging for trigger arcs., 資料番号: AA0049206095, レポート番号: JAXA-SP-05-001E

A magnetic sail is the way to propel a spacecraft by the solar wind in the interplanetary space. Although original concept of the magnetic sail depends solely on very large magnetic field generated by using such device as superconductors coil, in 2001, Winglee et al. proposed an efficient method to realize a huge magnetic field around a spacecraft with an assistance of plasma emission. From their theoretical analysis of what they call as mini-magnetospheric plasma propulsion (M2P2), it was shown that if a dense plasma were exhausted near the center of the dipole magnetic field, the magnetic field can be expanded far away from the spacecraft, thus the energy of the solar wind can be captured by this huge magnetic field in spite of very low-density solar wind. Based on the idea of such plasma sail, firstly studied were deep space missions targeting at some outer satellites like Jupiter. Plasma sail has great advantage against other electric propulsion systems because of its ability to produce larger thrust to power ratio. However, the thrust formula shown by Winglee et al. is doubtful in some respects. Therefore, an analysis model is discussed that can describe a process of the magnetic field inflation accompanied by plasma emission from the spacecraft., 資料番号: AA0046978013, レポート番号: JAXA-SP-03-001

試験技術ワークショップ 宇宙航空研究開発機構 20050913 茨城 日本, Workshop on Environmental Testing Japan Aerospace Exploration Agency 20050913 Ibaraki Japan, 本資料は2005年9月13日に行われたワークショップで発表に使われた資料をまとめたものである。発表は以下の7のタイトルについて行われた。1. 深宇宙・惑星における磁場観測の手法と科学的意義、2. 磁気試験設備の特性把握について、3. 熱真空環境における分子状コンタミネーション管理技術の検討、4. 13 mΦスペースチャンバソーラシミュレータ系キセノンランプ交換作業の効率化、5. HTV構造系開発状況と構造設計、6. コンポーネントのランダム振動試験におけるフォースリミット試験法の適用例、7. 音響負荷時のパネル搭載機器の質量による振動レベル予測手法, 資料番号: AA0049055000, レポート番号: JAXA-SP-05-009