Python code for Titan's spin state

Tidal dissipation in satellites affects their orbital and rotational evolution and their ability to maintain subsurface oceans. However, a satellite’s dissipation rate, parameterized by k2/Q, is hard to measure and is only known for the Moon and Io. Here we show that Titan’s measured departure from its expected rotation state can be used to infer k2/Q and its boundary layer dissipation parameter K/Cs. Over the likely range of ocean and ice shell thicknesses, we infer a K/Cs of 6.3x10-14 s-1 – 2.4x10-10 s-1, a k2/Q of 0.058–0.12, and a minimum dissipation factor Q≈5. Titan’s dissipation parameters are one to two orders of magnitude larger than the Moon’s and suggest an interior with a low effective viscosity. Titan’s dissipation rate implies that its orbital eccentricity and inclination are damping rapidly, consistent with an excitation within the last ~350 Myr. Titan’s predicted tidal response could be measured by the forthcoming Dragonfly lander, and JUICE could use our approach to det..., This document contains all of the Python code to reproduce the results, figures, and tables in Downey & Nimmo (2024). At the end of the file are the specific commands to call to create each figure and to output a number that is used in the text. No collected data were used in this work., , # Python code for Titan's spin state

[https://doi.org/10.5061/dryad.cvdncjtcw](https://doi.org/10.5061/dryad.cvdncjtcw)

## Description of the data and file structure

Files are written in Python (.py)

### Files and variables

Satellite_parameters.txt

* Contains all of the variable values for the Moon, Titan, Io, Europa, Ganymede, and Callisto
* References for each value are commented at the end of each line
* Python format

python_code_DowneyNimmo.py

* Python code to make figures and output important numbers

## Code/software

Python is needed to run the code, but only a text editor is needed to view the file.

The top commented section of the code is a table of contents for the methods in the file. The code is structured into 1) parameters 2) equations and 3) routines to output numbers and create the 2 Python figures in the paper and the 1 figure in the Supplementary Materials. The end of the document contains all the commands needed to reproduce the figures and numbers in the pub...