Daphnis, Saturn’s wavemaker moon, was captured in a rare photo by NASA’s Cassini spacecraft. Cassini made one of its passes around the planet, grazing the outer edges of Saturn’s rings on January 16, 2017. This is the closes view ever taken of the small moon.
Daphnis is only 5 miles across, and orbits within Saturn’s 26-mile-wide Keeler Gap, Space Daily reports. The Keeler Gap is located in the planet’s A Ring, some 155 miles from the ring’s outer edge. Daphnis was discovered here in 2005 by Voyager. The moon was found to induce waves both vertically and horizontally in the edges of the Keeler Gap.
The view from Cassini in the photo causes the gap to appear narrower than it actually is, because of the angle.
Daphnis, like Saturn’s other small moons Atlas and Pan, appears to show a narrow ridge around its equator, and a fairly smooth surface that could be composed of fine particles from the rings. A few craters can also be seen, and an additional ridge running parallel to the equatorial band is noticeable on its northern portion.
The image also captures some finer details, such as a grainy texture that could hint at particles clumping together. The wave peak in the Keeler Gap edge also makes the edges appear softer. There is a faint tendril of material following Daphnis, which may have resulted from when the moon drew material from the ring, which then spread itself out.
Cassini’s image was taken in visible light with the spacecraft’s narrow-angle camera from a distance of approximately 17,000 miles from Daphnis. The image scale is 551 feet per pixel. More formally known as Cassini-Huygens, the unmanned spacecraft was sent by NASA to study Saturn in 2004. It was the first spacecraft to enter the planet’s orbit, and has been beaming back images of Saturn and its many moons since its arrival, giving scientists valuable insight on the planet’s workings.