Cassini Captures Breathtaking View of Saturn's Dione

Cassini Image of Dione — Cassini spacecraft obtained this image of Saturn's moon Dione on June 16, 2015. (Image credit: NASA/JPL-Caltech/Space Science Institute)

On Tuesday (June 16), NASA's Cassini mission had an EXTREMELY close encounter with one of Saturn's cratered moons, Dione.

At a distance of only 321 miles (516 kilometers), this close approach was Cassini's fourth flyby of its mission — but it wasn't the closest. During the spacecraft's third flyby on Dec. 12, 2011, Cassini swooped only 62 miles (99 kilometers) from the moon's cratered surface.

PHOTO: Cassini Gets Final, Stunning View of Saturn's Moon Hyperion

This image, captured by Cassini's narrow-angle camera, was photographed when the mission was 48,000 miles (77,000 kilometers) away and the plane of Saturn's rings can be seen in the background. [Cassini's Amazing Photos of Saturn]

This is the penultimate flyby of Dione before Cassini's mission enters its final stage.

Preparations have begun to swing the spacecraft out of Saturn's ring plane and into a polar orbit — it will then be commanded to begin orbiting though Saturn's rings, giving scientists an unprecedented look at the gas giant's ring environment.

But the best is yet to come; the next moon after Dione on Cassini's checklist is mysterious Enceladus, where the probe will make a breathtakingly-close pass of only 30 miles (48 kilometers) from the icy moon's surface. Enceladus is now known to hide a liquid ocean under its icy crust and, through a system of polar geysers the moon is venting salty water vapor into space and mission scientists hope to use this close pass to further study the composition of this vapor.

This article was provided by Discovery News.

Ian O'Neill is a media relations specialist at NASA's Jet Propulsion Laboratory (JPL) in Southern California. Prior to joining JPL, he served as editor for the Astronomical Society of the Pacific‘s Mercury magazine and Mercury Online and contributed articles to a number of other publications, including Space.com, Space.com, Live Science, HISTORY.com, Scientific American. Ian holds a Ph.D in solar physics and a master's degree in planetary and space physics.