The Grand Canyon of the Colorado River is simply amazing when viewed from an orbital perspective. You instinctively recognize it, even though you have never seen it from this vantage point before. Somehow, your brain can warp all those vacation memories from visiting the South Rim into something recognizable. (Click on the images to see them full-size.)
But the amazement doesn’t stop there. Sometimes your brain can play little tricks. Under some lighting conditions the Grand Canyon does not look like a canyon at all. Instead, all you see are the arteries on a giant heart, as if someone were performing open heart surgery on Mother Earth.
Push on the corners of your eyes one more time, wait for the flashes to disappear, and now you see something entirely different. Instead of looking out the window of a spacecraft, you are looking out the window of a deep-sea submersible at some mucky-bottom seascape. You now see worms lying on top of the benthic sediment, happily doing whatever worms do on the bottom of the ocean.
So often, in the search for truth in nature, human perception masks how things really are.