中气层的红色精灵

2020年7月4日

Meeting in the Mesosphere
Image Credit & Copyright: Stephane Vetter (TWAN, Nuits sacrees)

Explanation: A sensitive video camera on a summit of the Vosges mountains in France captured these surprising fireworks above a distant horizon on June 26. Generated over intense thunderstorms, this one about 260 kilometers away, the brief and mysterious flashes have come to be known as red sprites. The transient luminous events are caused by electrical breakdown at altitudes of 50 to 100 kilometers. That puts them in the mesophere, the coldest layer of planet Earth’s atmosphere. The glow beneath the sprites is from more familiar lighting though, below the storm clouds. But on the right, the video frames have captured another summertime apparition from the mesophere. The silvery veins of light are polar mesospheric clouds. Also known as noctilucent or night shining clouds, the icy clouds still reflect the sunlight when the Sun is below the horizon.

Tomorrow’s picture: Saturn six-sided

中气层的红色精灵
影像提供与版权: Stephane Vetter (TWAN, Nuits sacrees)

说明: 在今年6月26日，一部位在法国．佛日山脉山顶的高灵敏录影机，捕捉到意外出现在远方地平线上空的“烟火”。这些神秘短暂的亮闪，是由远在260公里之外的活跃雷暴系统所产生的红色精灵。这些短暂发光事件，是雷暴系统在50至100公里高空造成的介电崩溃。也因此，这种现象出现在地球大气中最冷的中气层。红色精灵下方雷暴云底部的辉光，我们则较为熟悉。此外影像定格右侧，也记录了另一种出现在中气层的夏季辉光，纹理如叶脉的银白极区中气层云。这种云种又称为夜光云，是太阳没入地平面后，仍然在高空反射阳光的冰晶云。

明日的图片: Saturn six-sided