巴黎的夏至夜
影像来源与版权:Michel Loic

说明:6月21日的夜晚是地球北纬地区时长最短的夜晚,因此位于北纬48.9度的巴黎也不例外。尽管如此,这座光明之城仍然异常明亮。在夏至日落后,天空中布满了银色的夜光云。流星尘或火山灰上的冰冷凝结物悬浮在太空边缘,它们位于中气层最大高度、强烈的阳光下。在夏季的高纬度地区,我们可以看到引人注目且广泛分布的北方夜光云。
翻译:北京天文馆

A Solstice Night in Paris
Image Credit & Copyright: Michel Loic

Explanation: The night of June 21 was the shortest night for planet Earth’s northern latitudes, so at latitude 48.9 degrees north, Paris was no exception. Still, the City of Light had an exceptionally luminous evening. Its skies were flooded with silvery night shining or noctilucent clouds after the solstice sunset. Hovering at the edge of space, the icy condensations on meteoric dust or volcanic ash are still in full sunlight at the extreme altitudes of the mesophere. Seen at high latitudes in summer months, stunning, wide spread displays of northern noctilucent clouds are now being reported.
Astronomy Picture of the Day 06/28/2019