Star Cluster Evolution on the Hertzsprung-Russell Diagram

Simulation of a star cluster Hertzsprung-Russell Diagram as the cluster evolves from 100,000 years old to 19 billion years old.
The cluster has 30,000 stars with a Salpeter initial mass function and solar metallicity from 0.3 to 30 Msun. The green line is the zero-age main sequence for solar-metallicity stars. Star point sizes on the H-R diagram are scaled as the log of the stellar radius to give a sense of the radius at each time, and the gratuitous point colors are based on effective temperature of the star at that time. A tiny bit of random jitter in (L,T) is added at each time step to make this look a little more like a real H-R diagram.
Stellar evolution tracks and isochrones are drawn from the MIST v1.1 database (Choi et al. 2016, ApJ, 823, 102). The frames for the animation was created in Python using matplotlib and the read_mist_models() function, and composed into this video using ffmpeg and iMovie.
The one missing piece is that we don't yet have a way to depict the white dwarf cooling sequence, which is why there are so few white dwarfs (all you see are cores on the cooling sequence to where the MESA models stop following them). That's in the works...
This video has no audio track.
Created 2017 Oct 18 by Prof. Richard Pogge, The Ohio State University. My OSU colleague Marc Pinsonneault improved this video by helpfully suggesting raising the lower mass cut used on the IMF.
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