Convert Chain (ch) to Petameter (Pm) instantly.
About these units
Chain (ch)
A chain is equal to 66 feet or 4 rods, and it was standardized by surveyor Edmund Gunter in the 17th century. "Gunter's chain," consisting of 100 metal links, became the backbone of land surveying in the English-speaking world for centuries. Its convenience stems from simple arithmetic: 10 square chains make an acre, making land area calculations straightforward. Railroads, farmland, and city parcels across the United States and the Commonwealth nations were once laid out using chains, so the unit appears in countless historical records. Even today, some legal property descriptions still reference chain-based measurements, making the unit relevant for modern surveyors who interpret old maps. Although high-precision digital equipment has replaced physical chains, the unit's structural role in land division ensures its lasting importance.
Petameter (Pm)
A petameter is 10¹⁵ meters and begins bridging the gap between solar system scales and the nearest stars. Distances between stars, the size of large cosmic structures, or the wavelengths of extremely low-frequency electromagnetic waves may be expressed in petameters. For example, a light-year is about 9.46 petameters. Petameters rarely appear in everyday astronomical writing because traditional units like light years and parsecs are more intuitive to astronomers and the public. However, the unit's alignment with SI conventions makes it essential in scientific computation and large-scale modeling, especially when dealing with cosmic distances while maintaining strictly metric consistency.