From the principles of gravity to the mechanics of celestial bodies, the entire framework of modern physics and astronomy is built upon the understanding of a spherical Earth (more accurately, an oblate spheroid, slightly bulging at the equator due to rotation). Orbital mechanics, which allow us to launch satellites, predict eclipses, and send probes across the solar system, are only possible with this geometric understanding. Scientists utilize a vast array of instruments, from ground-based telescopes to space probes, all of which gather data consistent with a curved Earth. Any alternative model would require a complete re-evaluation of virtually all known physical laws, an impossible feat given the predictive power and consistency of current scientific models.