土星与木星大近合

2020年12月15日

Great Conjunction: Saturn and Jupiter Converge
Illustration Credit & Copyright: Sebastian Voltmer

Explanation: It’s happening. Saturn and Jupiter are moving closer and will soon appear in almost exactly the same direction. Coincidentally, on the night of the December solstice — the longest night of the year in the north and the longest day in the south — the long-awaited Great Conjunction will occur. Then, about six days from now, Saturn and Jupiter will be right next to each other — as they are every 20 years. But this juxtaposition is not just any Great Conjunction — it will be the closest since 1623 because the two planetary giants will pass only 1/10th of a degree from each other — well less than the apparent diameter of a full moon. In the next few days a crescent moon will also pass a few degrees away from the converging planets and give a preliminary opportunity for iconic photos. The featured illustration shows the approach of Saturn and Jupiter during November and December over the French Alps.

Growing Gallery: Notable images of the Great Conjunction submitted to APOD

Tomorrow’s picture: meteor sky

土星与木星大近合
图示提供与版权: Sebastian Voltmer

说明: 这是个进行中的事件。目前土星与木星逐日接近，过不久它们会几乎在同一方向。而这个大近合会出现在冬至那晚，正好落在一年之中，北半球黑夜和南半球白画最长的那天。所以再过6天，就会有每20年一现，土星和木星几乎贴在一起的景观。不过，这次的视觉错置不光只是造就一次大近合而已，而是自1623年以来最接近的一次，届时这2颗巨行星，会以1/10度、远小于月亮视张角的间距擦身而过。而在接下来的这数天之中，蛾眉月也会以数度的间距通过这对近合的行星附近，让想拍下历史性照片者有机会先练手。这张主题图示，呈现11月和12月从法国阿尔卑斯山出看出去，土星与木星逐渐靠近的历程。

影像画廊: 提交给APOD的大近合的著名图像

明日的图片: meteor sky