2025年12月23日
Red Sprites and Circular Elves Lightning over Italy
Image Credit & Copyright: Valter Binotto
Explanation: What’s happening in the sky? Lightning. The most commonly seen type of lightning involves flashes of bright white light between clouds. Over the past 50 years, though, other types of upper-atmospheric lightning have been confirmed, including tentacled red sprites and ringed ELVES. Although both last only a small fraction of a second, sprites are brighter and easier to photograph than their more common electrical-discharge cousins. ELVES are rapidly expanding rings that are thought to be created when an electromagnetic pulse shoots upward from charged clouds and impacts the ionosphere, causing nitrogen molecules to glow. Capturing either form of lightning takes patience and experience — capturing them both together, since they usually occur separately, is rare. The featured image is a frame from a video recorded from Possagno, Italy late last month above a distant thunderstorm over the Adriatic Sea.
Tomorrow’s picture: mystery dots
意大利上空的红色精灵与圆形精灵闪电
影像提供与版权: Valter Binotto
说明: 什么正在天空中发生？闪电。最常见的闪电类型是在云层之间出现的闪光，这些闪光通常是明亮的白光。然而，在过去的50年中，其他高空大气闪电类型已被确认，包括触手般的红色精灵和环状的淘气精灵（ELVES）。虽然这两者都只持续极短的时间，但红色精灵比其常见的电气放电亲戚更明亮且更容易拍摄。淘气精灵是快速扩展的环状闪电，目前认为是由带电云层放电所产生向上的电磁脉冲撞击电离层导致氮分子发光而形成的。拍摄这两种闪电都需要耐心和经验-由于它们通常是分开发生的，因此同时拍摄两者非常罕见。主题影像截取自上个月底在意大利 波萨尼奥（Possagno）拍摄的一段视频，影片拍摄远处亚得里亚海上空的一场雷暴之上。
明日的图片: mystery dots
