绕太阳转
(原标题: Circling the Sun)
2024-01-13
浏览次数: 12
地球绕太阳运行的轨道不是圆形，而是椭圆形。这颗美丽的行星在其椭圆轨道上离太阳最近的点被称为近日点。今年，近日点是在1月2日01:00 UTC，地球与太阳的距离比在远日点（去年7月6日）近300万英里，远日点是其椭圆轨道上的最远点。当然，与太阳的距离并不能决定季节，也不能决定日晕的大小。当太阳隐藏在高大的树干后面时，这个美丽的冰晕围绕太阳形成了一个22度宽的圆圈，更容易看到，这是在德国赫罗尔德施塔特附近的乡村散步时拍摄到的。太阳日晕的22度角直径是由漂浮在地球大气层高处的水冰晶的六面几何形状决定的。
查看原文解释
rth's orbit around the Sun is not a circle, it's an ellipse. The point along its elliptical orbit where our fair planet is closest to the Sun is called perihelion. This year, perihelion was on January 2 at 01:00 UTC, with the Earth about 3 million miles closer to the Sun than it was at aphelion (last July 6), the farthest point in its elliptical orbit. Of course, distance from the Sun doesn't determine the seasons, and it doesn't the determine size of Sun halos. Easier to see with the Sun hidden behind a tall tree trunk, this beautiful ice halo forms a 22 degree-wide circle around the Sun, recorded while strolling through the countryside near Heroldstatt, Germany. The Sun halo's 22 degree angular diameter is determined by the six-sided geometry of water ice crystals drifting high in planet Earth's atmosphere.
© Radoslav Zboran