2025年3月9日
Cyclones at Jupiter’s North Pole
Image Credit: NASA, JPL-Caltech, SwRI, ASI, INAF, JIRAM
Explanation: Why are there so many cyclones around the north pole of Jupiter? The topic is still being researched. NASA’s robotic Juno mission orbiting Jupiter took data in 2018 that was used to construct this stunning view of the curious cyclones at Jupiter’s north pole. Measuring the thermal emission from Jovian cloud tops, the infrared observations are not restricted to the hemisphere illuminated by sunlight. They reveal eight cyclonic features that surround a cyclone about 4,000 kilometers in diameter, just offset from the giant planet’s geographic north pole. Similar data show a cyclone at the Jovian south pole with five circumpolar cyclones. The south pole cyclones are slightly larger than their northern cousins. Oddly, data from the once Saturn-orbiting Cassini mission has shown that Saturn’s north and south poles each have only a single cyclonic storm system.
Tomorrow’s picture: california red
木星北极的气旋
影像提供: NASA, JPL-Caltech, SwRI, ASI, INAF, JIRAM
说明: 为何木星的北极有这么多气旋？此问题目前仍是研究的题材。美国国家航空航天局的朱诺号探测器于2018年所取得的数据，用于建构这幅呈现木星北极奇特气旋的影像。这项量测木星云顶热辐射的红外光观测，并不仅限于受到阳光照耀的半球。观测显示在木星北极稍偏离此巨行星磁北极之处，有个直径大约为4,000公里的气旋，其周围则环绕着8个气旋。其他类似的数据显示，木星南极也有个中心气旋，不过它的周围仅有5个环绕的气旋，而且这些南极气旋也略大于北极气旋。有趣的是，先前探索土星的卡西尼号任务之观测数据显示，土星的北极与南极都各只有单个气旋系统。
明日的图片: california red
