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Three months before its scheduled arrival at Saturn, the Cassini spacecraft has observed two storms in the act of merging. With diameters close to 1,000 kilometers (621 miles), both storms, which appear as spots in the southern hemisphere, were seen moving west, relative to the rotation of Saturn's interior, for about a month before they merged on March 19 through 20, 2004. This set of eight images was taken between Feb. 22 and March 22, 2004. The top four frames span 26 days. They are portions of images from the narrow angle camera taken through a filter accepting light in the near-infrared …