风车与星像迹线
2020 April 17
The Windmill and the Star Trails
Image Credit & Copyright: Antonio Gonzalez
Explanation: Stars can’t turn these old wooden arms, but it does look like they might in this scene from a rotating planet. The well-composed night skyscape was recorded from Garafia, a municipality on the island of La Palma, Canary Islands, planet Earth. The center of the once working windmill, retired since 1953, is lined-up with the north celestial pole, the planet’s rotation axis projected on to the northern sky. From a camera fixed to a tripod, the star trails are a reflection of the planet’s rotation traced in a digital composite of 39 sequential exposures each 25 seconds long. Brought out by highlighting the final exposure in the sequence, the stars themselves appear at the ends of their short concentric arcs. A faint band of winter’s Milky Way and even a diffuse glow from our neighboring Andromeda Galaxy also shine in the night.
Tomorrow’s picture: just another day
风车与星像迹线
影像提供与版权:Antonio Gonzalez
说明:在这幅摄于一颗旋转行星上的影像里,恒星看似想转动这座风车,但却无法带动这些老旧的木质扇叶支架。这张取景佳妙的夜空影像,摄于地球.加那利群岛.拉帕尔马岛的加拉菲亚镇。这座在1953年起即停用的风车之中心,恰好和地球自转轴所指的北天极重合。因此对三脚架上的相机而言,这些由39张曝光时间为25秒的照片合成之星像迹线,只是地球在自转的映射。而位在这些短同心圆弧迹线顶点的恒星,则是来自在此系列影像最后一祯特别经过强化处理的照片。在这幅影像所呈现的夜空里,还可见到冬季银河的淡影及仙女座大星系的弥漫辉光。
明日的图片:just another day
好像转起来的陀螺,真好看