日落后的近合景观

2020年12月19日

Conjunction after Sunset
Image Credit & Copyright: Alireza Vafa

Explanation: How close will Jupiter and Saturn be at their Great Conjunction? Consider this beautiful triple conjunction of Moon, Jupiter and Saturn captured through clouds in the wintry twilight. The telephoto view looks toward the western horizon and the Alborz Mountains in Iran after sunset on December 17. The celestial gathering makes it easy to see Jupiter and fainter Saturn are separated on that date by roughly the diameter of the waxing crescent Moon. On the day of their Great Conjunction, solstice day December 21, Jupiter and Saturn may seem to nearly merge though. In their closest conjunction in 400 years they will be separated on the sky by only about 1/5 the apparent diameter of the Moon. By then the two largest worlds in the Solar System and their moons will be sharing the same field of view in telescopes around planet Earth.

Tomorrow’s picture: volcanic conjunction

日落后的近合景观
影像提供与版权: Alireza Vafa

说明: 在大近合时，木星和土星会靠得多近呢？这幅摄于这个冬天暮光时分的薄云后方之月亮、木星和土星三重近合景观，可作为参考。这张于12月17日落后摄于伊朗的长焦镜头影像，呈现阿勒布尔兹山脉后方的西方天空景象。在这个天体派对里，木星与较暗的土星之间距，约莫与上弦月的视张角相当。而在12月21日冬至大近合那天，木星与土星会几乎重叠。在这个400年来间距最小的大近合里，它们在天空的间隔只有满月视直径的五分之一。届时从世界各地的望远镜看出去，这二颗太阳系最大行星和它们的卫星，全都聚在窄窄的一片视野里。

明日的图片: volcanic conjunction