Copyright:
Daniele Boffelli
原文:
Auroras usually occur high above the clouds. The auroral glow is created when fast-moving particles ejected from the Sun impact the Earth’s magnetosphere, from which charged particles spiral along the Earth’s magnetic field to strike atoms and molecules high in the Earth’s atmosphere. An oxygen atom, for example, will glow in the green light commonly emitted by an aurora after being energized by such a collision. The lowest part of an aurora will typically occur at 100 kilometers up, while most clouds usually exist only below about 10 kilometers. The relative heights of clouds and auroras are shown clearly in the featured picture from Dyrholaey, Iceland. There, a determined astrophotographer withstood high winds and initially overcast skies in an attempt to capture aurora over a picturesque lighthouse, only to take, by chance, the featured picture along the way.
中文翻譯:
🌌 #極光 #Aurora #Dyrholaey #冰島 #Iceland
極光通常發生在雲層之上高空。極光的光輝是由太陽噴發出來的快速運動粒子影響地球的磁層所形成的。這些帶電粒子沿著地球的磁場螺旋運動，撞擊高於地球大氣層的原子和分子。例如，氧原子在這種碰撞中被激活後會發出常見的綠光。極光的最低部分通常發生在約100公里的高度，而大部分雲層則存在於10公里以下。這幅來自冰島Dyrholaey的圖片清楚地顯示了雲層和極光的相對高度。在那裡，一位堅定的天文攝影師忍受著強風和最初的陰雲，努力捕捉極光在美麗燈塔上的景象，結果卻意外地拍下了這幅精彩的圖片。
#自然奇觀 #天文攝影 #光之舞 #旅遊 #攝影 #香港 #成長發展
來源:NASA每日圖片
