Space-time Variation of Aurora and Geomagnetic Disturbances : Auroral Observations at Syowa Station in Antarctica (AERONOMY)

• Main Authors: Takeo HIRASAWA, Katsutada KAMINUMA
• Format: Report
• Language: English
• Published: Geophysics Research Laboratory, University of Tokyo 1970
• Subjects: Antarctic; Syowa Station; Antarc*; Antarctica
• Online Access: https://nipr.repo.nii.ac.jp/?action=repository_uri&item_id=524; http://id.nii.ac.jp/1291/00000524/; https://nipr.repo.nii.ac.jp/?action=repository_action_common_download&item_id=524&item_no=1&attribute_id=18&file_no=1

The program of auroral observations carried out by the 8th wintering party of the Japanese Antarctic Research Expedition, 1967-1968, consisted of 1. All-sky camera 2. Visual and photographic observations of aurora 3. Observation of auroral pulsations 4. Auroral photometry along the geomagnetic meridian 5. Observation of the auroral radio noise. Description of each observation and results obtained are briefly summarized in the following. 1. Space-time variations of aurora and geomagnetic disturbances A meridian scanning photometer was designed for investigating the time and space variations of auroral luminosity. The meridian time-sequence of auroral luminosity (4278Å) was derived from the data obtained by this photometer. Based on this meridian time-sequence of aurora, the space and time variations of aurora during the auroral substorms and the magnetic field variations associated with the auroral displays are investigated in detail. 2. Auroral pulsations A special photometer was designed for investigating the detailed characteristics of auroral pulsations and their relationships with geomagnetic pulsations. Auroral pulsations observed at Syowa Station can be classified into the following five types : A. Irregular fluctuations with large amplitudes observed mostly at the onset of an auroral substorm. B. Pulse-like auroral pulsations with a period of about 20-40 seconds. C. Long-lived auroral pulsations with a sinusoidal waveform. Their period and amplitude are about 10 seconds and a few KR, respectively. D. Rapid fluctuations of auroral luminosity with a period of about 0.5-2.0 seconds. E. Extremely rapid fluctuations with a frequency of about 20-30 Hz. Characteristics of each auroral pulsation are investigated and summarized.