2025年12月15日
Gemini Meteors over Snow Capped Mountains
Image Credit & Copyright: Tomáš Slovinský
Explanation: Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Gemini. That is why the major meteor shower in December is known as the Geminids — because shower meteors all appear to come from a radiant toward Gemini. Three dimensionally, however, sand-sized debris expelled from the unusual asteroid 3200 Phaethon follows a well-defined orbit about our Sun, and the part of the orbit that approaches Earth is superposed in front of the constellation of Gemini. Therefore, when Earth crosses this orbit, the radiant point of falling debris appears in Gemini. Featured here is a composite of many images taken over the past few days through dark skies from Slovakia and capturing the snow-covered peaks of the Belianske Tatra mountains Numerous bright meteor streaks from the Geminids meteor shower are visible. Orion is visible above the horizon, while the bright star nearest the radiant is Castor.
APOD Review: RJN’s Night Sky Network Lecture
Tomorrow’s picture: tree sprites
双子座流星雨划过白雪覆盖的山峦
影像提供与版权: Tomáš Slovinský
说明: 这些流星究竟都来何方？从天空中的方向来看，最直接的答案指向双子座。这就是为什么十二月的主要流星雨被称为双子座流星雨，因为流星雨的流星似乎都来自一个双子座方向的辐射点。然而，从三维空间来看，这些沙粒大小的碎片是从不寻常的小行星3200 Phaethon所喷出，并沿着一个围绕太阳的固定轨道运行，而接近地球的轨道部分正好位于双子座的前方。因此，当地球穿过这条轨道时，坠落碎片的辐射点看起来就像出现在双子座方向。这里展示的是过去几天在斯洛伐克晴朗夜空下拍摄的多张照片的合成图，捕捉了白雪皑皑的贝利安斯塔特拉山脉（Belianske Tatra）的山峰。图中清晰可见来自于双子座流星雨中无数明亮的流星划过天际。猎户座在地平线以上可见，而最接近辐射点的亮星是北河二。
APOD回顾: RJN的夜空网路讲座
明日的图片: tree sprites
