Mangold Ellipse
This painting by Robert Mangold, 4 color frame painting #9, got me playing around with rectangles defining an ellipse. (I don't think his is a true ellipse, though.)
This is actually a conic through 5 points, but I don't think you can make a circle. Parabola seems unlikely, but is a hyperbola possible?
![Image](https://stage.geogebra.org/resource/w762frpu/ijk7JRYmoqga7R1F/material-w762frpu.png)