Scientific consensus and centuries of empirical evidence—from satellite imagery and global navigation to consistent astronomical observations—drive the overwhelming 99.3% market-implied probability that Earth is not flat. Traders recognize the flat-Earth narrative as a persistent fringe conspiracy theory amplified in certain online communities and viral pop-culture moments, yet it lacks any verifiable support from credible institutions or data. Recent years have seen no credible challenges or new findings that could shift this view, with historical precedents like Eratosthenes' ancient measurements reinforcing the round-Earth model. Realistic upset scenarios remain virtually nonexistent, as any reversal would require dismantling established physics, geography, and technology, outcomes far outside plausible cultural or scientific trajectories.