木星与土星大近合：电影
2020年12月30日
Jupiter and Saturn Great Conjunction: The Movie
Video Credit: Thanakrit Santikunaporn (National Astronomical Research Institute of Thailand); Text: Matipon Tangmatitham
Explanation: Yes, but have you seen a movie of Jupiter and Saturn’s Great Conjunction? The featured time-lapse video was composed from a series of images taken from Thailand and shows the two giant planets as they angularly passed about a tenth of a degree from each other. The first Great Conjunction sequence shows a relative close up over five days with moons and cloud bands easily visible, followed by a second video sequence, zoomed out, over 9 days. Even though Jupiter and Saturn appeared to pass unusually close together on the sky on December 21, 2020, in actuality they were still nearly a billion kilometers apart. The two gas giants are destined for similar meet ups every 19.86 years. However, they had not come this close, angularly, for the past 397 years, and will not again for another 60 years. If you’re willing to wait until the year 7541, though, you can see Jupiter pass directly in front of Saturn.
Gallery: Notable images of the Great Conjunction submitted to APOD
Tomorrow’s picture: open space
木星与土星大近合：电影
影片提供: Thanakrit Santikunaporn (National Astronomical Institute of Thailand); 文稿提供: Matipon Tangmatitham
说明: 你看过记录木星与土星大近合的影片吗？由一系列摄于泰国的照片建构而成的这部主题缩时影片，就呈现这二颗巨行星以1/10度间距擦身而过的景象。影片的第一部分，以较小的视野呈现它们在5天期间的行踪，其中月亮及行星的云带皆清楚可见。影片接着拉远，呈现它们在后来9天之间的旋舞。纵然在2020年12月21日那天，木星与土星在天空中看来格外接近，但其实它们仍然相隔将近10亿公里。这二颗巨行星类似的近合景观，每19.86年就会复现。不过，它们在过去的397年之中，从没这么接近过，而下次要再出现类似的大近合，得再等个60年。除此之外，如果你愿意苦等到7541年，就能见到木星直接掩过土星的前方。
明日的图片: open space
