Last one until 2038
On October 6, 2025, at 05:31 UTC I was lucky enough to catch one of the rarest events visible from Earth: Titan, Saturn’s largest moon, casting its shadow on the planet’s cloud tops while the moon itself transited the disk.
In the image you can clearly see:
- Titan (the bright dot to the right of Saturn) moving in front of the planet
- Titan’s round, inky-black shadow projected onto Saturn’s northern hemisphere
- Four smaller moons labeled: Rhea, Dione, Tethys, and Mimas (Tethys is almost lost in the rings)
Captured with the Meade 10″ LX200 EMC, ZWO ASI715MC color planetary camera, SVBony UV/IR cut filter and a ZWO Atmospheric Dispersion Corrector (ADC) to keep the colors sharp at low altitude.
Why this is the last one for 13 years
Saturn’s equator (and its moons) is currently almost edge-on to Earth. Titan’s shadow can only fall on the planet when we see the rings nearly edge-on. After 2025 the ring tilt rapidly opens up, moving the shadows of the inner moons off the disk. The geometry won’t line up again until the rings close once more in 2038–2039. So this really was the final Titan shadow transit visible from Earth this Saturnian year.
A once-in-a-generation event from my backyard in Williamsburg, Virginia.
Hope you enjoy the view — the next chance comes when many of us will be a little grayer!
George
AstroCreation