Convert Aln (aln) to Earth's Polar Radius (R⊕ (p)) instantly.
About these units
Aln (aln)
The aln was a traditional Swedish unit of length equal to roughly 59.4 cm, though its exact value varied slightly by region and period. It belongs to the broader family of "ell" measurements used across Europe, originally based on the length of a human forearm. The aln played a crucial role in Swedish commerce, especially in the textile industry, where cloth was measured by stretching it along standardized rods or boards marked in aln lengths. Because such goods were often woven locally and traded regionally, the aln helped regulate and unify commercial practices before the adoption of the metric system. Although obsolete today, the aln survives in historical texts, architectural references, and Scandinavian museum records. Understanding the aln helps scholars interpret pre-modern construction records, land measurements, and traditional clothing industries, revealing a great deal about everyday life in early Sweden.
Earth's Polar Radius (R⊕ (p))
The Earth's polar radius is approximately 6,356.8 km, slightly shorter than the equatorial radius due to the Earth's flattening at the poles. This measurement is critical in modeling Earth's shape, gravity field, and rotation. It impacts satellite orbits, geodetic surveys, and global positioning systems (GPS). The difference between the equatorial and polar radii also explains phenomena such as centrifugal force variations, equatorial bulges, and sea level differences across latitudes. Understanding R⊕ (p) is essential for precision navigation, Earth science, and astronomy.