This green dot was persistent—following me for 15 minutes and moving around to meet me no matter where I stood. The first time it happened, my father had been dead for one week. My mother and I were in the Smoky Mountains in Tennessee, in April, trying to do something with ourselves. We were walking an overlook with long views across the ridgelines when something appeared in the air in front of us. Not in a photograph. Not on a screen. In the air. A shaft of colored light — blues and greens — moving as we moved, present in a way that had no business being there on a clear afternoon with no rain, no prism, no explanation. My mother raised her camera toward it. I have that photograph. She is standing at the stone wall, back to me, pointing her camera at something that should not be there. She saw it too. We both did, with our own eyes. And then after a few minutes it was gone. We hadn’t changed anything. It just left. Tennessee, 2021. I know what some people will say. Lens smudge. Camera artifact.…