Saturn’s moon Tethys ‘hangs like a droplet’ on the planet’s rings

18 October 2014 Astronomy Now
Image: NASA/JPL-Caltech/Space Science Institute
Image: NASA/JPL-Caltech/Space Science Institute

Like a drop of dew hanging on a leaf, Saturn’s moon Tethys appears to be stuck to the planet’s A and F rings in this view from the Cassini probe.

Tethys (1,062 kilometres or 660 miles across), like the ring particles, is composed primarily of ice. The gap in the A ring through which Tethys is visible is the Keeler gap, which is kept clear by the small moon Daphnis (not visible here).

This view looks toward the Saturn-facing hemisphere of Tethys. North on Tethys is up and rotated 43 degrees to the right. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on July 14, 2014.

The view was acquired at a distance of approximately1.8 million kilometres (1.1 million miles) from Tethys and at a Sun-Tethys-spacecraft, or phase, angle of 22 degrees. Image scale is 11 kilometres (7 miles) per pixel.

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