this cascading accordion stitches together 23 images, side-by-side, in sequence (3.5 inches height by width expandable to 7.2 feet). each image is sourced from NASA's SDO/AIA project, then enlarged, excerpted to illustrate the transit as a cascading accordion (as if from the perspective of another craft traveling alongside Mercury), with a NASA image of Mercury superimposed over the Mercury black hole in the original photographs.