Enceladus Near Saturn
影像提供: Cassini Imaging Team, SSI, JPL, ESA, NASA
Explanation:
Some images of Saturn appear surreal. Earlier this year, the robot spacecraft Cassini now orbiting Saturn took this surreal image of the gas giant Saturn, its majestic rings, and its enigmatic world Enceladus all in one frame. Enceladus, recently found to emit jets of ice from possible underground seas, appears white as its surface is covered with relatively clean water-ice. Below Enceladus are the rings of Saturn, seen nearly edge on. Compared to Enceladus, Saturn's rings show their comparatively high density of dirt with their golden-brown color in this natural color image. The planet Saturn, in the background, appears relatively featureless with the exception of thin ring shadows visible on the upper left. The terminator between night and day is seen vertically across the face of this distant world.
說明:
有些土星影像很超現實。今年初，繞行土星的卡西尼號探測船拍下這幅超現實影像，同時呈現了氣態巨行星--土星、壯麗的行星環以及它神祕的衛星土衛二。土衛二表面下可能有個海洋，不久之前剛被發現會發出冰噴流，而在較乾淨新冰覆蓋下的土衛二顯得很潔白。土衛二下方的橫紋是土星幾乎側視的行星環，在這幅自然色彩影像裡，因為土星環含有較大量的塵埃，它在土衛二的襯托下呈現棕黃的色澤。影像背景的土星除了左上角落的行星環暗影外，看起來很平淡無奇。這個遙遠行星的日夜交界線幾乎垂直切過這幅影像。
名詞對照：土衛二 (Enceladus )、卡西尼號探測船 (Cassini spacecraft )、日夜交界線 (terminator)。
資料來源: Scientific American
Department of Physics, NCKU
