Twice each year, the sun and the Earth arrive at a moment of balance — day and night held briefly equal — and this Tuesday, that ancient threshold falls across the United States once more. What makes this equinox quietly remarkable is that modern cities, built on grids with no celestial intention, have become accidental observatories: stand at the right intersection and the sun sets like a stone dropped down a canyon of glass and steel. It is a reminder that the rhythms older than civilization still move through the landscapes we have built over them, and that the impulse to witness them has n