南方的双子座
(原标题: Geminids of the South)
2021-12-16
浏览次数: 35
12月13日至14日晚，在乌拉圭南部拍摄的这张照片中，萤火虫沿着月光下的乡村闪烁。那天晚上，一年一度的双子座流星雨在多云的天空中落下了流星。在1.5小时内记录的帧在相机朝南的合成图像中对齐。这个方向与流星雨向北的辐射方向相反，所以双子座流星雨的条纹似乎在南方地平线以下的反辐射处汇合。然而，流星雨的视辐射（和反辐射）只是由于角度的不同。当地球扫过神秘的3200号小行星法厄同的尘埃轨迹时，形成双子座流星雨的尘埃颗粒实际上是沿着平行的轨迹移动的。它们以每秒22公里的速度进入地球大气层。
查看原文解释
Fireflies flash along a moonlit countryside in this scene taken on the night of December 13/14 from southern Uruguay, planet Earth. On that night meteors fell in the partly cloudy skies above during the annual Geminid meteor shower. Frames recorded over a period of 1.5 hours are aligned in the composite image made with the camera facing south. That direction was opposite the shower's radiant toward the north and so the Geminid meteor streaks appear to converge at an antiradiant below the southern horizon. The shower's apparent radiant (and antiradiant) is just due to perspective though. As Earth sweeps through the dust trail of mysterious asteroid 3200 Phaethon, the dust grains that create the Geminid shower meteors are really moving along parallel tracks. They enter Earth's atmosphere traveling at about 22 kilometers per second.
© Fefo Bouvier