Moons Near Jupiter Image Credit & Copyright: Betul Turksoy Explanation: On May 20, a nearly Full Moonand Jupiter shared this telephoto field of view. Captured when a passing cloudbank dimmed the moonlight, the single exposure reveals the familiar face of ourfair planet's own large natural satellite, along with bright Jupiter (lowerright) and some of its Galilean moons. Lined up left to right the tiny pinpricksof light near Jupiter are Ganymede, Europa, [Jupiter] and Callisto. (That's notjust dust on your screen ...) Closer and brighter, our own natural satelliteappears to loom large. But Ganymede, and Callisto are physically larger thanEarth's Moon, while water world Europa is only slightly smaller. In fact, ofthe Solar System's six largest planetary satellites, Saturn's moon Titan ismissing from the scene and a fourth Galilean moon, Io, is hidden by our rulinggas giant. 木星附近的衛星們 5月20日,一輪近乎圓滿的滿月和木星貢獻了這幅望遠鏡視野下的美景。這幅單張曝光影像拍攝于一片浮云遮擋月光之時,它呈現出我們熟悉的天然衛星(月球)的面孔,以及明亮的木星(右下方)和它的伽利略衛星們(注)。從左到右排列在木星附近的小亮點依次是木衛三(蓋尼米德)、木衛二(歐羅巴)、木星和木衛四(卡里斯托)(別擦了,那些不是你屏幕上的灰塵...)。我們地球的衛星離得更近,更加明亮,因此顯得更為龐大。但是實際上,木衛三和木衛四的體積比月球還要大,而充滿水的世界木衛二比月球只是稍小一點。實際上,在太陽系最大六顆衛星中,除了上文提到的四顆,土星的衛星土衛六在并沒有出現在這幅畫面中,而排行第四的木衛一則被龐大的氣態巨星所遮擋。 注: 伽利略衛星,木星的四個大型衛星,由伽利略于1610年1月7日首度發現。 參考文獻: https://apod./apod/image/1905/DSC_9154TurksoyMay21MJ2048.jpg 近期文章: Astronomy Picture of the Day——“天涯海角” |
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