Starspot Animations

Today I gave a short talk at Cool Stars 18, detailing some of my recent research on determining starspot evolution from stars in Kepler. A few people asked to see my animations from the talk, so I thought I would include a few of them here:

Here is the "logo" I made for the talk, which outlines the geometry of the systems we're studying. This shows dark spots rotating in/out of view as the star rotates, and a transiting exoplanet that zips past more frequently than the rotation period. This does not represent an actual star/planet system, but is simply instructive:

Next is the example of how a starspot on a rotating stellar surface (left) affects the light curve over time (right). We have also included some inclination on the star:

Click image for animated gif (1.8mb)

Finally, a movie that demonstrates the finer detail features that we see during exoplanet transits, allowing us to break interesting degeneracies in determining the spot properties:

12 days of data from Kepler 17 from James Davenport on Vimeo.


For the curious, tools I'm using to make these:

• Python - to compute model light curves
• IDL - to render frames to .eps (could be done w/ Python)
• ImageMagik - to convert frames to .jpeg or .gif
• gifsicle - to create animated gif's
• ffmpeg - to create .mp4 movies

Update: I've also posted a tutorial on making high quality animations with IDL (much of which is applicable to making animations in Python)

If you'd like to use any of these animations in your presentations, please include a note that gives attribution to me!