Deep royal blue and brilliant emerald green are juxtaposed to dramatic effect in this image. Although we know we’re looking at Earth from above, let that thought slip for a moment to appreciate the intricately layered composition of lines, shapes and textures. We’re actually looking at the visual rhythms of the Mississippi River Delta and its many human-created levees, dams and spillways. The Gulf of Mexico frames the land on the lower right part of the image. Looking inland from the Gulf, do you see the largest lake? The port city of New Orleans sits on its banks, saved from tides and floods only by major river engineering.