Statute League
A statute league is a traditional unit of distance used primarily on land and defined as 3 statute miles, which equals about 4.83 kilometers or 15,840 feet. It was commonly used in English-speaking countries for measuring distances before the metric system became widespread. The statute league is different from the nautical league, which is based on nautical miles and used at sea. Although largely obsolete today, the statute league is still found in historical texts and older maps.
X-unit
The X-unit (symbol: xu) is a very small unit of length used primarily to measure wavelengths of X-rays and gamma rays. It was introduced in the early 20th century for precision measurements in X-ray crystallography.
1 X-unit ≈ 0.1 picometers (pm) or 10⁻¹³ meters
It allows scientists to express extremely small wavelengths typical of X-rays, which are on the order of atomic spacing
The exact definition has varied historically, but the unit remains useful for comparing wavelengths in X-ray spectroscopy and crystallography
Though largely replaced by the picometer or ångström in modern usage, the X-unit played a crucial role in early developments of atomic-scale measurement.
No conversions available for length.