木星─土星大近合：有大红斑参与的盛会
2020年12月23日
Jupiter Meets Saturn: A Red Spotted Great Conjunction
Image Credit & Copyright: Damian Peach
Explanation: It was time for their close-up. Two days ago Jupiter and Saturn passed a tenth of a degree from each other in what is known a Great Conjunction. Although the two planets pass each other on the sky every 20 years, this was the closest pass in nearly four centuries. Taken early in day of the Great Conjunction, the featured multiple-exposure combination captures not only both giant planets in a single frame, but also Jupiter’s four largest moons (left to right) Callisto, Ganymede, Io, and Europa — and Saturn’s largest moon Titan. If you look very closely, the clear Chilescope image even captures Jupiter’s Great Red Spot. The now-separating planets can still be seen remarkably close — within about a degree — as they set just after the Sun, toward the west, each night for the remainder of the year.
Gallery: Notable images of the Great Conjunction submitted to APOD
Tomorrow’s picture: open space
木星─土星大近合：有大红斑参与的盛会
影像提供与版权: Damian Peach
说明: 献上它们大近合的特写影像。在上星期，木星与土星以1/10度的间距擦身而过，为我们带来大近合的景观。虽然这种景象每20年一现，但这次的大近合，是将近400年来最接近的一次。这幅摄于大近合那天稍早、由多张照片组成的影像，不但记录到这二颗巨行星出现在同一视野里，更捕捉到木星的四颗大卫星之身影，从左到右它们分别是：木卫四、木卫三、木卫一和木卫二，以及土星的最大卫星─土卫六。如果细细检视，就会发现这幅智利望远镜影像，更拍到木星的大红斑。这二颗已逐渐分道扬镳的行星，仍然非常接近，目前的间距不到1度。而在今年底的这段时间，西方天空的它们，每晚都紧随在太阳之后西沉。
明日的图片: open space
