Our house looks out onto the Pacific Ocean, in the far distance where water meets the horizon. I have been looking out onto that view ever since we moved here, just being grateful for the beauty of it and the perspective it offers when my mind is foggy.
Then one day a friend visited and observed that looking out to the horizon, it was possible to see the curvature of the Earth. I took a look and sure enough the ocean curves down to the right. Once seen, I have never been able to un-see it. At times I find the view a little unsettling. The water of the ocean 'staying in place' as it curves down and out of sight.