Search

Unusual current-voltage characteristics were found by the Fast Langmuir Probe measurement inside sporadic E (Es) layer during S-520-29 sounding rocket flight. The characteristics are caused by a significant gradient of electron density inside the Es layer. We employ a new analysis method for accurate estimation of the electron temperature and density. It also allows us to obtain the temperature and density in a shorter time interval than the voltage sweep period. Our new observation and analysis method provide us with first detailed structure of electron density and temperature inside the Es layer with an unprecedented spatial resolution. The maximum electron density and the minimum electron temperature observed inside Es layer are estimated to be 9.7×10(exp 5) cm-3 and 550 K, respectively, at an altitude of 98 km. The total thickness of the layer is about 1 km. Furthermore, the detailed trend of the electron temperature from its boundary toward the center of Es layer was revealed so clearly owing to the new method. Electron temperature in the surrounding region of the Es layer is found to be quite high, suggesting significant heating at the altitude range. The observed reduction of electron temperature in the Es layer embedded in an elevated temperature region is interpreted in terms of dependence of heat sources and cooling processes on the thermal electron density., 形態: 図版あり, Physical characteristics: Original contains illustrations, 資料番号: AA1830006000, レポート番号: JAXA-RR-18-002E

Accepted: 2016-10-03, 資料番号: SA1160122000

Accepted: 2011-02-07, 資料番号: SA1002583000

Accepted: 2007-07-31, 資料番号: SA1000145000

S-310-33号機は大気光縞々構造の生成メカニズムの解明を主目的として2004年1月18日0時30分に鹿児島県内之浦宇宙空間観測所から打ち上げられた。本ロケットに搭載されたFLP(高速ラングミューアプローブ)は高度約80km以上での電子温度、電子密度を測定するために開発された。これらのデータは同時に測定される酸素原子密度や中性大気の風とともに議論に用いられ、特に熱圏下部における中性大気と電離大気間の熱エネルギー収支と力学、運動量輸送に関する総合的な研究が行なわれる。ロケットの飛翔時にはFLPは1部不具合があったものの、良好なデータを取得して電子温度と電子密度を算出することが可能であった。観測データからは局所的な温度構造、密度構造が得られた他、飛翔時に高度89km付近に著しく密度勾配が急な領域が存在したことを明らかにしている。, S-310-33 sounding rocket was launched from Uchinoura Space Center in Kagoshima on January 18th, 2004. The Fast Langmuir Probe (FLP) onboard the rocket was developed to measure the electron temperature and number density above 80 km altitude in the ionospheric D and E regions. These data are used to investigate the generation mechanism of wavy airglow structure which is a main scientific topic in the present sounding rocket experiment, together with the atomic oxygen density and the neutral wind simultaneously measured on the rocket. The FLP can provide a spatial distribution of the electron temperature and density along the rocket trajectory, which will also be used to discuss the dynamics and energetic in the lower thermosphere. During the rocket flight, the FLP successfully measured the voltage versus current relationship of the probe, from which the electron temperature and density can be estimated, despite a minor problem with the electronic circuit. Both the electron temperature and density indicate a spatial structure which suggests a possible existence of the dynamical process. It is noticeable that the FLP observed very steep gradient of the electron density at 89 km altitude., 資料番号: AA0048467002, レポート番号: JAXA-SP-04-007

大気光波状構造形成過程の解明を目的とするWAVE2004キャンペーンの一環として、観測ロケットS-310-33号機ロケット実験が行われた。本ロケット実験では、酸素原子密度・電子密度・大気光発光強度の鉛直分布を観測したほか、微細な大気波動の特性を解明するため中間圏・下部熱圏での風系を高精度で直接測定できるフォイル・チャフを用いた観測を行った。測定は高度96-85kmの領域で行われ、高度89km以上では非常に強い北向きの風が、それ以下では東向きの風が卓越していたことが分かった。また同じくS-310-33号機に搭載されたラングミュアプローブ(FLP)および中波帯電波受信機(MFR)の観測から、高度89km付近において急激な電子密度の変動があったとされている。本研究では、この89km付近にみられる電子密度の変動と中性風との関係について、Wind shear理論で説明できるか検証を行った。, Foil chaff experiment using a sounding rocket S-310-33 was carried out during the WAVE2004 campaign. This is a campaign to study the formation process of the waves in the airglow structures. S-310-33 was launched at 0:30 JST on the 18th January 2004, from Uchinoura, Japan and about 20,000 foils were successfully ejected and tracked by primary radar. The velocity vector of the neutral wind was obtained in the height range of 96 - 85 km. The results indicate a very strong northward wind above 89 km and an eastward wind below. Preliminary results of Fast Langmuir Probe (FLP) and Medium Frequency Receiver (MFR) show that electron density has a significant increase at about 89 km. This density variation is analyzed based on wind shear theory using the neutral wind observation., 資料番号: AA0048467003, レポート番号: JAXA-SP-04-007

1970年代初頭から行われてきた観測ロケット実験により、電離圏D領域、E領域、F領域のプラズマに関する測定が行われてきた。これらの測定の中でも電子温度観測は最も頻繁に行われてきた項目の1つであるが、その統計的解析により限られた条件(冬季の午前11時前後、高度105〜110km)で電子温度が背景に対し局所的に数100Kから1,000K上昇する高電子温度層が存在することが報告されている。新規開発の測定器を観測ロケットに搭載し、高電子温度層生成メカニズムの解明を目指すロケット実験を提案中である。本実験で用いられる新しい観測手法は将来の観測ロケット、地球周回衛星、惑星探査機に搭載可能であろう。本稿では高電子温度層観測のあらましを述べるとともに、解明のためのロケット実験計画の目的、方法などについて述べる。, 資料番号: AA0046920049

A Venus orbiter mission is going to be proposed as one of the future Japanese planetary missions. The primary objective is to reveal the mechanism of the atmospheric general circulation. The mission will reveal also ionospheric circulation, atmospheric escape processes and geologic activities. The spacecraft will be launched in February–April of 2007 by a M-V rocket of ISAS and arrive at Venus in September of 2009. The spacecraft will be inserted into an elliptical equatorial orbit with a period of 21.3 hours. The outline of the mission is presented in this paper.

LESは熱圏観測実験用のロケット搭載機器であり，2011年度に計画しているNASA-ISASの国際共同ミッションで使用する計画である．当該装置は2007年に打ち上げられたS-520-23号機で実用されており，リチウムガス噴射に成功している．国際共同ミッション向けには観測ロケット用から一部改良を加え，設計の見直しを行った．本報告は，機器設計と製作の結果についてまとめたものである．, Lithium ejection system (LES) is one of the chemical payloads for the ionosphere observation. Lithium is selected as the chemical tracer to detect optically the neutral winds, and the thermite loaded in LES played a role of the heat sauce to vaporize the solid phase lithium. This device has been launched by the Japanese sounding rocket, S-520, from Uchinoura space center in 2007. Gaseous lithium was successfully injected into the space, and the red colored cloud was able to be observed from the ground. The concept was explained in early papers, and their design was shown that the thermite including lithium or sodium pellets was directly charged in the canister. Thermite is ignited by the pyrotechnics and generates the high temperature chemical products which give the vaporization energy of the released materials. The payload design was considered that the instruments on board which acts by the pyrotechnics need to be equipped with the safe and arm device (SAD) from the safety standard. The final design obtained the safety and the reliability of this device for storing and handling. Lithium in the canister is able to be removed with ease, and the tracer materials will be able to replace lithium to other one if necessary. 13 LES canisters were fabricated for ISAS-NASA international collaborative space science mission. This paper reports the results of the design study and the specification of LES., 形態: カラー図版あり, Physical characteristics: Original contains color illustrations, 資料番号: AA0064908000, レポート番号: JAXA-RR-10-011

著者人数: 15名, Accepted: 2011-03-22, 資料番号: SA1003051000