Development of ship-borne all-sky imager system for the airglow and aurora observations

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K21900
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 17:Earth and planetary science and related fields
• Research Institution: Kyoto University
• Principal Investigator: Saito Akinori 京都大学, 理学研究科, 准教授 (10311739)
• Co-Investigator(Kenkyū-buntansha): 坂野井 健 東北大学, 理学研究科, 准教授 (80271857)
• Project Period (FY): 2019-06-28 – 2022-03-31
• Keywords: 電離圏 / 中間圏 / 大気光 / オーロラ / 船上観測 / 南極観測船「しらせ」

Outline of Final Research Achievements

This study developed a set of all-sky imagers that can be installed on a ship to observe the ionosphere over the oceans, which is a void area for observation. Since the ionospheric structures spread over an area of more than 5,000 km, it is impossible to obtain a complete picture of the ionospheric phenomena by limited observations over land. Ionospheric observation techniques over ocean areas is needed. Because of the faint emission of the airglow, the airglow imagers for the ionospheric observations require long exposure time. In this system, the imagers were mounted on a gimbal to compensate for the movements and vibrations of the ship. The system was installed on the Antarctic research vessel, "Shirase", and carried out the observations during its cruises between Japan and the Syowa station, Antarctica for three periods: November 2019 to March 2020, November 2020 to February 2021, and November 2021 to March 2022.

Free Research Field

超高層大気物理学

Academic Significance and Societal Importance of the Research Achievements

近年GPSや「みちびき」などのGNSSによる衛星測位について高い精度と信頼性が求められており、GNSSの電波に対する電離圏構造が与える影響・障害が問題になっている。電離圏構造の移動する領域は5,000km以上に及ぶため、陸域上空の限られた観測ではその全体像の把握は不可能であり、海域上空の電離圏観測手段の開発が必要とされている。本研究では、比較的小型でありながら高精度・広範囲の電離圏撮像観測が可能な船舶搭載用の大気光・オーロラカメラの開発に成功し、日本と南極昭和基地の往復の航路上において観測を実施することでその実用性を示すことができた。