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Such sunspots are a common, but are less frequent as we head toward solar minimum, which is the period of low solar activity during its regular approximately 11-year cycle. This sunspot is the first to appear after the sun was spotless for two days, and it is the only sunspot group at this moment. Like freckles on the face of the sun, they appear to be small features, but size is relative: The dark core of this sunspot is actually larger than Earth. Credits: NASA’s Goddard Space Flight Center/SDO/Joy Ng, producer
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Section 1

Rhea is a heavily-cratered, airless world, while Titan’s nitrogen-rich atmosphere is even thicker than Earth’s. This natural color image was taken in visible light by the Cassini spacecraft on Nov. 19, 2009, at a distance of approximately 713,300 miles (1,148,000 kilometers) from Rhea. After a nearly 20-year mission that overflowed with discoveries, the Cassini spacecraft ended its mission on Sept. 15, 2017. Credit: NASA/JPL-Caltech/Space Science Institute