瑞典上空的旗帜状极光

2021年03月14日

A Flag Shaped Aurora over Sweden
Image Credit & Copyright: Mia Stålnacke

Explanation: It appeared, momentarily, like a 50-km tall banded flag. In mid-March of 2015, an energetic Coronal Mass Ejection directed toward a clear magnetic channel to Earth led to one of the more intense geomagnetic storms of recent years. A visual result was wide spread auroras being seen over many countries near Earth’s magnetic poles. Captured over Kiruna, Sweden, the image features an unusually straight auroral curtain with the green color emitted low in the Earth’s atmosphere, and red many kilometers higher up. It is unclear where the rare purple aurora originates, but it might involve an unusual blue aurora at an even lower altitude than the green, seen superposed with a much higher red. Now past Solar Minimum, colorful nights of auroras over Earth are likely to increase.

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瑞典上空的旗帜状极光
影像提供与版权: Mia Stålnacke

说明: 在短暂的期间，它酷似一面高50公里的镶边旗帜。在2015年3月中旬之时，一例强烈的日冕物质抛射，顺着毫无遮拦的磁通道直冲地球而来，引起了近年来较强烈的地球磁暴。而视觉效应之一，是造成了广及数个国家的大片地球磁极区，都可见到的极光活动。这幅摄于瑞典．基鲁纳镇的主题影像，呈现了大片不寻常的直纹极光帘，其中，绿极光来自较低层的地球大气，而红极光则源自更高数十公里之处。目前并不确定罕见的紫极光之来源为何，但它可能和出现在绿极光下方的蓝极光有关，在视线上它和远方的高层红极光重叠。目前太阳已离开活动极小期，故地球出现多彩极光的夜晚预期夜将会持续下去。

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明日的图片: meteor heard