An impact crater is one of the sizes the mind refuses to hold. We picture a hole; the reality is a wound tens or hundreds of kilometres across. Each one here is drawn as a circle of its true diameter, with the worn remnant that survives today nested inside the original rim.
Drag a crater across the map and watch a single asteroid's mark balloon over whole countries — the same Mercator illusion that puffs up the north, told with a scar instead of a nation.