Created in Maya 2017 for Kathryn Hadley’s PH 205 course.

This animation explains how multiple forces interact to create unique forms of tidal flexing on the moons of Jupiter. It can be complicated to consider all the effects of rotating, orbiting, accelerating, bulging, and gravity pulling that contribute to a moon being kneaded like dough (and thus warming internally).

The trick with this video was to setup all the effects quickly, by noting how Earth’s moon works, and then revisit each effect in more detail for the less stable interactions of moons around Jupiter. It was also very tricky to gauge how much to simulate reality verses separating out the different effects in a simplified fashion – to show how they layer on top of each other.

Exactly when and how Io speeds up and slows down during it’s elliptical orbit was the toughest thing to simulate accurately (we ended up closely studying a specific simulation at http://astro.unl.edu/classaction/animations/renaissance/kepler.html to get it right).

As for learning objectives, the teacher notes:
“The changing speed of Io as it nears Jupiter is a critical thing here. It is one of the main points of what I am teaching about orbital dynamics. This motion is addressed in other parts of the course, not just this video, and it would be confusing to students to stress Keplerian motion everywhere but here.”