Convert Earth's Equatorial Radius (R⊕) to Mile (US Survey) (mi (US)) instantly.
About these units
Earth's Equatorial Radius (R⊕)
The Earth's equatorial radius is approximately 6,378.1 km. This distance represents the radius measured along the equator, where Earth's rotational bulge makes it slightly larger than the polar radius. Geodesists, cartographers, and astronomers use the equatorial radius for mapping, satellite positioning, and calculating gravitational effects. It is fundamental to defining the shape of the Earth as an oblate spheroid rather than a perfect sphere. Precise knowledge of R⊕ enables accurate navigation, climate modeling, and orbital calculations, forming the basis for modern geodesy and Earth observation systems.
Mile (US Survey) (mi (US))
The US Survey Mile equals 5,280 US Survey Feet (~1,609.347 meters). Slightly longer than the international mile due to the use of the US survey foot, it has been essential for mapping, transportation planning, and geodetic calculations in the United States. Surveyors and engineers relied on the US survey mile to ensure precise alignment of property boundaries, railroad tracks, and infrastructure projects. Over long distances, even small differences between the US survey and international mile can accumulate significantly, necessitating care in measurement. Though the international mile is now standard, the US survey mile remains important for interpreting historical maps, legal descriptions, and older engineering plans.