Convert Handbreadth (handbreadth) to Earth's Equatorial Radius (R⊕) instantly.
About these units
Handbreadth (handbreadth)
The handbreadth, roughly 0.1 meter, represents the width of a human hand with fingers extended. It served as a convenient, body-based subunit for cubits and larger measures. Handbreadths were integral to construction, tailoring, and craftwork, allowing precise division of larger units into manageable increments. In ancient Egyptian, Greek, and Hebrew measurement systems, the handbreadth facilitated scaling and proportioning for artisans and builders. Today, the handbreadth is mainly of historical interest, helping reconstruct ancient architectural plans and understand the human-centered logic of early measurement systems.
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.