Morphometric Study of Craters on Saturn's Moon Rhea.

Area of Science:

• Planetary Science
• Geology
• Astrogeology

Background:

• Impact craters on icy moons provide insights into surface modification processes.
• Processes like viscous relaxation and ejecta deposition alter crater topography.
• Understanding these modifications helps constrain interior structure and surface properties.

Purpose of the Study:

• To analyze morphometric measurements of craters on Rhea.
• To identify dominant post-impact modification processes on Rhea.
• To constrain Rhea's interior structure and surface properties.

Main Methods:

• Measured crater diameter, depth, and wall slope on Rhea.
• Classified craters into simple and complex types.
• Analyzed morphometric data for correlations and transitions.

Main Results:

• A linear correlation was found between impact crater depth-to-diameter ratio and crater wall slope.
• The simple-to-complex crater transition diameter for Rhea is 12 ± 2 km.
• No significant shallowing of large complex craters was observed.

Conclusions:

• Past heating events are likely the dominant modification process on Rhea.
• Rhea's surface properties are similar to other comparable icy bodies.
• The absence of a rheological transition suggests Rhea may not be fully differentiated.