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Cassini’s First Dive Between Saturn and Its Rings

After the first-ever dive through the narrow gap between the planet Saturn and its rings, NASA’s Cassini spacecraft called home to mission control at NASA’s Jet Propulsion Laboratory in Pasadena, California. See highlights from the scene at JPL on April 26-27, 2017, and some of the first raw images the spacecraft sent back from its closest-ever look at Saturn’s atmosphere. For more information about Cassini and its “Grand Finale,” visit .

Moon Shadows on Saturn

About this video (03-20-07)
Saturn’s wide, but very thin, rings are tilted with respect to its plane of orbit around the Sun. Once every 15 years, the rings are edge-on (perpendicular) to the Sun. During those times, some of Saturn’s moons can cast shadows across the rings.

This time-lapse movie shows the icy moons Enceladus, Mimas, Dione, and Tethys orbiting Saturn. Enceladus, seemingly chased by Mimas, is first to speed past the rings and in front of the planet. Both moons cast small shadows on the planet, but only Enceladus casts a shadow on the rings. The orbit of Mimas is inclined so that its shadow misses the rings. Dione is next, and its long shadow also tracks across the ring system. As the three moons move across Saturn’s disk, the viewer catches a fleeting view of Tethys as it moves behind the planet on the right.

The 30-second movie is created from Hubble images taken over a 9½-hour span. The images were taken Nov. 17, 1995, with Hubble’s Wide Field and Planetary Camera 2. The movie has a standard aspect ratio, but is presented within a widescreen frame – the black bars along the sides are normal.

E. Karkoschka (Arizona), G. Bacon (STScI)