Like Earth, Saturn is tilted on its axis. And, just as on Earth, as the sun climbs higher in the sky, shadows get shorter.
This image, snapped by the Cassini spacecraft’s wide-angle camera on 16 January 2015 around 2.5 million kilometres from Saturn, captured the moment when the gas giant’s shrinking shadow just barely reached across the entire main ring system. The shadow will continue to shrink until the planet’s northern summer solstice, at which point it will once again start lengthening across the rings, reaching across them in 2019.