土卫三十五与土星环

2019 November 3

Daphnis and the Rings of Saturn
Image Credit: NASA, JPL-Caltech, Space Science Institute, Cassini

Explanation: What’s happening to the rings of Saturn? A little moon making big waves. The moon is 8-kilometer Daphnis and it is making waves in the Keeler Gap of Saturn’s rings using just its gravity — as it bobs up and down, in and out. The featured image is a colored and more detailed version of a previously released images taken in 2017 by the robotic Cassini spacecraft during one of its Grand Finale orbits. Daphnis can be seen on the far right, sporting ridges likely accumulated from ring particles. Daphnis was discovered in Cassini images in 2005 and raised mounds of ring particles so high in 2009 — during Saturn’s equinox when the ring plane pointed directly at the Sun — that they cast notable shadows.

土卫三十五与土星环
影像提供: NASA, JPL-Caltech, Space Science Institute, Cassini

说明: 土星环发生了什么事？事情不大，只是一颗小卫星在鼓浪而已。这颗8公里宽的土卫三十五 ，随着它蹦上蹦下左摇右晃，它的重力也在土星环的基勒环缝内激起波浪。卡西尼号太空船在2017年告别轨道之一，曾拍摄并发布过一张照片，而上面这张主题影像 ，是那张照片的上色和较清晰的版本。影像中，土卫三十五位在影像的右缘，它的表面拥有可能是由环系粒子所聚成的凸脊。土卫三十五是在2005年发现于卡西尼号拍摄的影像里。在2009年土星分点、土星环面直指太阳之时，土卫三十五所激起的环系粒子凸峰，高耸到能在环面投下可分辨的影子。 (Daphnis 土卫三十五)