土星环里的地球和月亮
2020 May 27
Earth and Moon through Saturn’s Rings
Image Credit: NASA, ESA, JPL-Caltech, SSI, Cassini Imaging Team; Processing & License: Kevin M. Gill
Explanation: What are those dots between Saturn’s rings? Our Earth and Moon. Just over three years ago, because the Sun was temporarily blocked by the body of Saturn, the robotic Cassini spacecraft was able to look toward the inner Solar System. There, it spotted our Earth and Moon — just pin-pricks of light lying about 1.4 billion kilometers distant. Toward the right of the featured image is Saturn’s A ring, with the broad Encke Gap on the far right and the narrower Keeler Gap toward the center. On the far left is Saturn’s continually changing F Ring. From this perspective, the light seen from Saturn’s rings was scattered mostly forward , and so appeared backlit. After more than a decade of exploration and discovery, the Cassini spacecraft ran low on fuel in 2017 and was directed to enter Saturn’s atmosphere, where it surely melted.
Gallery: Notable Venus & Mercury Conjunction 2020 Images submitted to APOD
Tomorrow’s picture: open space
土星环里的地球和月亮
影像提供: NASA, ESA, JPL-Caltech, SSI, Cassini Imaging Team; 影像处理与授权: Kevin M. Gill
说明: 土星环缝里的这些亮点是什么？我们的地球和月亮！在3年多前，当太阳短暂受到土星遮掩时，卡西尼号太空船因此得以回首眺望太阳系内围。于是见到了远在14亿公里之外，如针尖光点大小的地球和月球。在这幅主题影像里，中偏右侧的是土星的A环，右缘附近的是宽广的恩克环缝，靠中的窄缝则基勒环缝，而在左缘的则是土星变动不休的F环。在这个视角里，来自土星环的光主要来自前向散射，因此看来像是环系的背光。在探索和发现土星系统十多年之后，卡西尼号太空船在2017年耗尽燃料，因此接获指令深入土星大气并销毁于其中。
相册：提交给APOD的值得注意的2020年金星和水星合相照片
明日的图片: open space
