After the post on Jupiter's "analemma" over $12$ years, I wanted to do the same for Venus, an inner planet. Venus' orbital period of $224.701$ days makes it so that $13$ orbits of Venus are approximately equal to $8$ Earth years (with the error being less than a day). This means that roughly every $8$ years Venus comes back to the same approximate position in the sky - good enough to consider it a closed curve as far as its "analemma" is concerned.
Since Venus is an inner planet, its mean meridian transit period is effectively a mean solar day. I took Stellarium screenshots with a gap of $6$ days spanning the required $8$ years. This was then rendered into a movie that I've uploaded to YouTube (see below).
A bonus is that the Sun's analemma can also be seen in the video as the Sun traces out the figure-8 curve near the central meridian.
Please manually select the High-Defintion (1080p) quality if YouTube serves up a lower quality version.
With the $(x,y)$ coordinates in the screenshots known already from Stellarium, I used the same script I had used earlier for Jupiter to trace out the "analemma" curve for Venus and overlay it on the first image. The resulting Lissajous curve and quite complex and beautiful. (Caveat: This curve was generated from a fresh set of screenshots so they won't line up with the frames in the video.)
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| Venus' "analemma" over $8$ years |
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