ナショナルジオグラフィックさんのインスタグラム写真 - (ナショナルジオグラフィックInstagram)「Photo by Babak Tafreshi @babaktafreshi | I've been a night-sky photographer since the 1990s, and this was the strongest, most colorful aurora I have ever photographed. It was March 2015, and I was finishing an annual photo workshop in Iceland when I noticed a major solar eruption heading for our planet. The particles take two days to arrive. I was well located but the challenge was the weather. The forecast took me to the iconic Kirkjufell falls in the west. The geomagnetic storm level was so high (Kp 9) that the aurora started at twilight, and an aurora crown formed about 10 times on a single night! NatGeo editors selected this image for the cover of the "Hidden Earth" special issue and also the best travel photos in 2017. Explore more of the world at night @babaktafreshi.」5月2日 17時02分