北半球夏季的暮光时分
Northern Summer Twilight
Image Credit & Copyright: Justin Anderson
Explanation: Nights grow shorter and days grow longer as the summer solstice approaches in the north. Usually seen at high latitudes in summer months, noctilucent or night shining clouds begin to make their appearance. Drifting near the edge of space about 80 kilometers above the Earth’s surface, these icy clouds were still reflecting the sunlight on June 14. Though the Sun was below the horizon as seen north of Forrest, Manitoba, Canada, they were caught in a single exposure of a near midnight twilight sky. Multiple exposures of the foreground track the lower altitude flash of fireflies, another fleeting apparition shining in the summer night.
Tomorrow’s picture: the season’s sunrise
北半球夏季的暮光时分
影像提供与版权: Justin Anderson
说明: 在北半球，随着夏至将临，夜晚渐短而白昼渐长。在此同时，夏季高纬度地区常见的夜光云也逐渐现踪。在6月14日子夜暮光时分，拍下天空单曝光影像的当时，从加拿大曼尼托巴省福雷斯特村的北边看出去，太阳已没入地平线之下，但漂流在80公里高太空边缘的这些冰晶云，仍在反射阳光。而组成影像前景的数张照片，则记录另一种夏夜的流光─地面附近萤火虫的亮闪。
明日的图片: the season’s sunrise
