By Bryan Hall | 2025-08-22
Rhea shadow transit on Saturn
On 09/09/2025 03:40 am by Steven Bellavia | Website | Smithfield, VA
Rhea is 1,528 Km in diameter, the second largest moon of Saturn, although one third the size of Titan, its largest moon at 5,150 Km.
Discovered by Giovanni Cassini in 1672, Rhea has a heavily cratered surface, with younger, smoother areas at its poles and equator. The moon is thought to be a mixture of water ice and rock, and while it was once thought to have rings, the Cassini mission revealed signatures that were interpreted as deorbiting ring material.
Telescope: 152mm, f/16 Explore Scientific Maksutov Cassegrain
Camera: ZWO ASI 290MC (my guide camera)
Mount: SkyWatcher EQ6R-Pro equatorial
Used Autostakkert to select, align and stack the best 2,160 of 7,200 frames from a 3-minute SERS video @40fps, 25 millisecond exposures, Gain 300.
wavelet sharpening/denoising in Lucien AstroSurface