巴黎上空的夜光云

巴黎上空的夜光云

ByNASA中文

2022年7月12日 Noctilucent Clouds over Paris Credit & Copyright: Bertrand Kulik Explanation: It’s northern noctilucent cloud season. Composed of small ice crystals forming only during specific conditions in the upper atmosphere, noctilucent clouds may become visible at sunset during late summer when illuminated by sunlight from below. Noctilucent clouds are the highest clouds known and now established to be polar mesospheric clouds observed from the ground. Although observed with NASA’s AIM satellite since 2007, much about noctilucent clouds remains unknown and so a topic of active research. The featured image shows expansive and rippled noctilucent clouds wafting over Paris, France. This year, several northern locations are already reporting especially vivid displays of noctilucent clouds. Tomorrow’s picture: webb begins 巴黎上空的夜光云 影像提供与版权: Bertrand Kulik 说明: 这是北半球夜光云的季节。特定条件下才会形成于高层大气中的微小冰晶，在夏季末日落时受到下方阳光的照耀时，偶而会以夜光云之姿现身。夜光云是现知最高的云种，在地面观测中被归类为极地中层云。虽然自从2007年，NASA的中气层水冰特性观测卫星 (AIM)，就持续在观测它，但夜光云的特性仍有诸多不明之处，所以依然是很活耀的研究题目。这幅主题影像，呈现了带着波纹飘过法国巴黎上空的大片夜光云。在今年，已有数个北纬地区报导目暏了特别华丽生动的夜光云。 明日的图片:…

巴黎的夏至夜

巴黎的夏至夜

ByNASA中文

2019 June 28 巴黎的夏至夜 影像来源及版权: 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。 A Solstice Night in Paris Image Credit & Copyright: Loic Michel 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.