“September 24, 2015. What looks like a pair of Saturnian satellites is actually a trio upon close inspection. Here, Cassini has captured Enceladus (313 miles or 504 kilometers across) above the rings and Rhea (949 miles or 1,527 kilometers across) below. The comparatively tiny speck of Atlas (19 miles or 30 kilometers across) can also be seen just above and to the left of Rhea, and just above the thin line of Saturn’s F ring. This view looks toward the unilluminated side of the rings from about 0.34 degrees below the ring plane.
The image was taken in visible light with the Cassini spacecraft narrow-angle camera. The view was obtained at a distance of approximately 1.8 million miles (2.8 million kilometers) from Rhea. Image scale on Rhea is 10 miles (16 kilometers) per pixel. The distance to Enceladus was 1.3 million miles (2.1 million kilometers) for a scale of 5 miles (8 kilometers) per pixel. The distance to Atlas was 1.5 million miles (2.4 million) kilometers) for an image scale at Atlas of 9 miles (14 kilometers) per pixel.”
Image credit: NASA/JPL-Caltech/Space Science Institute