2025年5月5日
Planet Lines Across Water
Image Credit & Copyright: Jose Antonio Hervas
Explanation: What’s causing those lines? Objects in the sky sometimes appear reflected as lines across water — but why? If the water’s surface is smooth, then reflected objects would appear similarly — as spots. But if the water is choppy, then there are many places where light from the object can reflect off the water and still come to you — and so together form, typically, a line. The same effect is frequently seen for the Sun just before sunset and just after sunrise. Pictured about 10 days ago in Ibiza, Spain, images of the rising Moon, Venus (top), and Saturn (right, faint) were captured both directly and in line-reflected forms from the Mediterranean Sea. The other bright object on the right with a water-reflected line is a beacon on a rock to warn passing boats.
Explore Your Universe: Random APOD Generator
Tomorrow’s picture: two black holes
划过水面的行星光痕
影像提供与版权: Jose Antonio Hervas
说明: 这些光痕是怎么产生的？低悬的天体有时会在水面倒映出线状的光痕，不过，为何如此？照说水面如果平滑如镜，倒映的天体看起来和本尊很像，形似光斑。然而，当水面有波澜起伏时，那么天体会从水面许多位置反射到观察者的眼里，经常形成线形的光痕。例如：刚东升的旭日和即将隐没的夕阳，就常会产生这种景观。这张大约10天前摄于西班牙 伊比萨岛的照片，记录了即将西落的月亮、金星（顶端）和右方较暗的土星，以及它们在地中海面的线形倒影。影像右方较亮、在水面映出线形光痕的光源，则是伫立岩石上、警示过往船只的灯塔。
探索你的宇宙: 随机APOD生成器
明日的图片: two black holes
