2020 May 31
Aurora over Sweden
Image Credit & Copyright: Göran Strand
Explanation: It was bright and green and stretched across the sky. This striking aurora display was captured in 2016 just outside of Östersund, Sweden. Six photographic fields were merged to create the featured panorama spanning almost 180 degrees. Particularly striking aspects of this aurora include its sweeping arc-like shape and its stark definition. Lake Storsjön is seen in the foreground, while several familiar constellations and the star Polaris are visible through the aurora, far in the background. Coincidently, the aurora appears to avoid the Moon visible on the lower left. The aurora appeared a day after a large hole opened in the Sun’s corona allowing particularly energetic particles to flow out into the Solar System. The green color of the aurora is caused by oxygen atoms recombining with ambient electrons high in the Earth’s atmosphere.
Tomorrow’s picture: red lagoon
说明: 满天都是明亮泛绿的极光。这片非常吸晴的极光，是在2016年摄于瑞典．厄斯特松德市的近郊。这幅几乎涵盖180度视野的主题全景影像，是由6张照片拼接而成。其中的极光最突出之特点，是它宽广和对比鲜明的光弧。影像中，位在前景的是Storsjön 湖，此外透过极光还可见到远方背景里的数个熟悉星座和北极星。很凑巧的是，这片极光看似在避让影像左下的月亮。这片极光出现在日冕发展出一个巨洞，让极高能量的粒子得以泛流进入太阳系的一天之后。 极光泛绿的色泽，是高层地球大气的氧原子和周围环境中的电子复合时，所释放出的光。
明日的图片: red lagoon