@infobeautiful
Do you have the source of the image ?

I was a little bit disturb by the triangle shape of the cercle and doing my own research i found something like that :
https://www.mapdevelopers.com/draw-circle-tool.php?circles=%5B%5B4978948.47%2C48.8521033%2C2.3298956%2C%22%23AAAAAA%22%2C%22%23000000%22%2C0%5D%5D

That seem to me more realistic for the projection from a globe to a cylinder : the cercle should look like an ellipse