Tethys Tops Saturn


An illusion of perspective, Saturn’s moon Tethys seems to hang above the planet’s north pole in this view from NASA’s Cassini spacecraft.

Tethys (1,062 kilometres or 660 miles across) is actually farther away than Saturn in this image. Lacking visual clues about distance, our brains place the moon above Saturn’s north pole. Tethys, like all of Saturn’s major moons and its ring system, orbits almost exactly in the planet’s equatorial plane.

This view looks toward the sunlit side of the rings from about 17 degrees above the ring plane. The image was taken with the Cassini spacecraft’s wide-angle camera on 26 January 2015 using a spectral filter which preferentially admits wavelengths of near-infrared light centred at 752 nanometres.

The view was acquired at a distance of approximately 3.4 million kilometres (2.1 million miles) from Saturn. Image scale on Saturn is 200 kilometres (120 miles) per pixel. Tethys has been brightened by a factor of three relative to Saturn to enhance its visibility.

Saturn: Exploring the Ringed Planet

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