Overwhelming scientific consensus from centuries of observations, satellite imagery, and space missions drives the 97.5% market-implied odds against a flat Earth, reflecting traders' recognition of established physics and empirical data that have consistently shaped public understanding. Recent cultural moments, including viral social media challenges and documentaries, have tested but ultimately reinforced this narrative without shifting the frontrunner status. Realistic upset scenarios remain minimal, such as an unforeseen global revelation or coordinated misinformation campaign gaining unprecedented traction, though historical patterns and ongoing verification from multiple independent sources make any reversal highly improbable before resolution.