How is a directional antenna pointed when making a “long-path” contact with another station?

Radio waves can travel around the Earth in two directions. The 'short path' is the most direct great-circle route to the target station. The 'long path' goes in the exact opposite direction, wrapping around the other side of the globe to reach the same destination. Because the Earth is a sphere, pointing your directional antenna exactly 180 degrees away from the direct, short-path heading will send your signal along the long path. This is especially useful when propagation conditions favor the longer route, such as when the daytime side of the Earth offers better ionization. Options mentioning the gray line or the rising sun are incorrect; while long-path propagation often occurs along the gray line, the specific heading to point the antenna is always the mathematical 180-degree reciprocal of the short path.