Sep 6, 2017

Successful filming of the fastest aurora flickering

 

Overview of the press release

The word "aurora" invokes an image of a slowly shimmering curtain of light illuminating the sky. However, when an explosive aurora occurs, known as a breakup, it sometimes leads to another phenomenon called "flickering". When an aurora "flickers" its brightness and motion in some areas begin to change rapidly. This flickering typically oscillates at a 1/10 second period, which is equivalent to the ion cyclotron frequency of oxygen ions.

Dr. Yoko Fukuda (formally of the Graduate School of Science at The University of Tokyo), Dr. Ryuho Kataoka of the National Institute of Polar Research, and other collaborators conducted a 3 year continuous high-speed imaging observation at Poker Flat Research Range, Alaska, USA, and identified the physics behind the flickering. They discovered the fastest flickerings of aurora ever observed at the periods of 1/60~1/50 and 1/80 of a second.

On March 19, 2016, the researchers observed an aurora with the brightness that ranked within the top 5 of all observations since 2014, and was filmed with a 1/160 second shutter speed camera. Detailed analysis of the footage showed a high-speed flickering aurora vibrating with a 1/80 second period taking place during the brightest moment of the breakup.

Figure: High-speed cameras installed at the Neal Davis Science Operations Center at the Poker Flat Research Range of the University of Alaska.

 

The research teams:
National Institute of Polar Research, The University of Tokyo, Nagoya University, Kyoto University, University of Alaska, Fairbanks and University of Southampton

 

For more information, please visit the website of National Institute of Polar Research.

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