2025年4月3日
The Da Vinci Glow
Image Credit & Copyright: Giorgia Hofer
Explanation: A 26 hour old Moon poses behind the craggy outline of the Italian Dolomites in this twilight mountain and skyscape. The one second long exposure was captured near moonset on March 30. And while only a sliver of its sunlit surface is visible, most of the Moon’s disk can be seen by earthshine as light reflected from a bright planet Earth illuminates the lunar nearside. Also known as the Moon’s ashen glow, a description of earthshine in terms of sunlight reflected by Earth’s oceans illuminating the Moon’s dark surface was written over 500 years ago by Leonardo da Vinci. Of course earthshine is just the most familiar example of planetshine, the faint illumination of the dark portion of a moon by light reflected from its planet.
Tomorrow’s picture: pixels in space
达文西灰光
影像提供与版权: Giorgia Hofer
说明: 在这幅暮色时分的山景与夜空影像里，月龄26小时的新月，低悬在义大利多罗迈山脉嶙峋的轮廓后方。这张1秒长曝光影像，则是摄于3月30日的月落时分。当时，尽管月亮只有一抺银白区受到阳光的直射，然而朝着地球的正面，在明亮地球反射光的照耀下，其余的区域皆可见。这种现象称为地照或月球灰光。500多年前，达芬奇就曾描述过这种现象，并解释其成因为“地球海洋所反射的阳光，能够微微照亮月球的夜面”。当然，行星反射的光都会微微照亮其卫星的夜面，因此地照只是行星照中最广为人知的例子。
明日的图片: pixels in space
