# Local Sun Model: The Tests It Cannot Pass The local Sun model tries to explain day and night by putting a nearby Sun above a flat Earth, often moving in a circle like a spotlight. It is visually simple, but it fails when asked to predict the sky from many places at once. ## Test 1: Sunsets If the Sun is nearby and moving away over a plane, it should shrink with distance and remain above the horizon unless special perspective rules are invented. Real sunsets show the Sun crossing the horizon while keeping nearly the same angular size. ## Test 2: Sunrise and Sunset Directions The compass direction of sunrise and sunset changes with latitude and date in a predictable way. A local Sun model must reproduce those directions for all observers, not just draw a light circle on a map. ## Test 3: Seasons Seasons are not just warmer and colder feelings. They include day length, solar-noon altitude, polar day/night, and opposite seasons between hemispheres. These patterns fit Earth’s axial tilt and orbit. ## Test 4: Time Zones Different longitudes experience solar noon at different times. On a globe, the relationship is simple: about one hour per 15 degrees of longitude. A flat model must preserve that timing while also matching directions and Sun angles. ## Test 5: Eclipses Solar and lunar eclipses are predicted years in advance. A local Sun and Moon model must predict not just that eclipses occur, but their exact timing, path, duration, and visibility from different locations. ## Test 6: Southern Skies Observers across the southern hemisphere see a coherent southern sky. A flat Earth with a local overhead Sun must also explain the stars, not just daylight. ## Use the Checker ## Bottom Line The local Sun model survives as a drawing because it stays vague. When forced to make the same kind of predictions that almanacs, navigators, photographers, farmers, astronomers, and ordinary observers use every day, it collapses into exceptions.