闪电

2020年9月27日 Lightning over Colorado Image Credit & Copyright: Joe Randall Explanation: Have you ever watched a lightning storm in awe? Join the crowd. Oddly, details about how lightning is produced remains a topic of research. What is known is that updrafts carry light ice crystals into collisions with larger and softer ice balls, causing the smaller crystals to become positively charged. After enough charge becomes separated, the rapid electrical discharge that is lightning occurs. Lightning usually takes a jagged course, rapidly heating a thin column of air to about three times the surface temperature of the Sun. The resulting shock wave starts supersonically and decays into the loud sound known as thunder. Lightning bolts are common in clouds during rainstorms, and on average 44 lightning…

2019 December 4 Electric Night Image Credit & Copyright: Ivan Pedretti Explanation: It may appear, at first, like the Galaxy is producing the lightning, but really it’s the Earth. The featured nighttime landscape was taken from a southern tip of the Italian Island of Sardinia in early June. The foreground rocks and shrubs are near the famous Capo Spartivento Lighthouse, and the camera is pointed south toward Algeria in Africa. In the distance, across the Mediterranean Sea, a thunderstorm is threatening, with several electric lightning strokes caught together during this 25-second wide-angle exposure. Much farther in the distance, strewn about the sky, are hundreds of stars in the neighborhood of our Sun in the Milky Way Galaxy. Furthest away, and slanting down from the upper…

2019 October 8 Sprite Lightning in HD Image Credit & Copyright: Stephane Vetter (TWAN) Explanation: This phenomenon occurs in the sky over our heads, not the sea. It is a type of lightning known as red sprite, and rarely has it ever been photographed in this detail. Even though sprites have been recorded for over 30 years, their root cause remains unknown. Some thunderstorms have them, but most don’t. These mysterious bursts of light in the upper atmosphere momentarily resemble gigantic jellyfish. A few years ago high speed videos were taken detailing how red sprites actually develop. The featured image was captured last month in high definition from Italy. One unusual feature of sprites is that they are relatively cold — they operate more like…

2019 September 18 Gigantic Jet Lightning over India Image Credit & Copyright: Hung-Hsi Chang Explanation: Yes, but can your lightning bolt do this? While flying from Munich to Singapore earlier this month, an industrious passenger took images of a passing lightning storm and caught something unexpected: gigantic jet lightning. The jet was captured on a single 3.2-second exposure above Bhadrak, India. Although the gigantic jet appears connected to the airplane’s wing, it likely started in a more distant thundercloud, and can be seen extending upwards towards Earth’s ionosphere. The nature of gigantic jets and their possible association with other types of Transient Luminous Events (TLEs) such as blue jets and red sprites remains an active topic of research. 印度上空的巨大喷流 影像来源与版权: Hung-Hsi Chang 说明：对了，你见过像这样的闪电吗？本月早些时候，一位勤劳的旅客在从慕尼黑飞往新加坡的途中，拍摄到一场正在发生的雷暴，并捕捉到一些意想不到的现象-巨大的喷流。这道喷流是在拍摄于印度巴德拉克上空的一幅曝光时长为3.2秒的影像中捕捉到的。尽管这道巨大的喷流似乎与飞机的机翼相连，但它很可能是从一片更遥远的雷云发出的，我们可以看到它朝着地球的电离层向上延伸。巨大喷流的本质及它与其他类型的瞬变发光事件（如蓝色喷流和红闪）的可能关联仍然是一个活跃的研究课题。

2019 July 29 Lightning over the Volcano of Water Image Credit & Copyright: Sergio Montúfar (Pinceladas Nocturnas) Explanation: Have you ever watched a lightning storm in awe? Join the crowd. Details of what causes lightning are still being researched, but it is known that inside some clouds, internal updrafts cause collisions between ice and snow that slowly separate charges between cloud tops and bottoms The rapid electrical discharges that are lightning soon result. Lightning usually takes a jagged course, rapidly heating a thin column of air to about three times the surface temperature of the Sun. The resulting shock wave starts supersonically and decays into the loud sound known as thunder. On average, around the world, about 6,000 lightning bolts occur between clouds and the…