Petameter
A petameter (Pm) is a unit of length in the metric system, equal to 1 quadrillion meters (1 petameter = 10¹⁵ meters). This unit is extremely large and is used mainly in astronomy and theoretical physics to describe vast distances, such as those between stars or galaxies. For example, one petameter is about 105.7 light years. Since it measures such enormous distances, the petameter is not used in everyday life or common scientific applications—it’s mostly used in discussions about the scale of the universe.
Rod
A rod is a traditional unit of length used in land measurement and surveying. It is equal to 16.5 feet, 5.5 yards, or exactly 5.0292 meters.
Also known as a pole or perch, the rod dates back to medieval England and was commonly used for measuring land and agricultural plots. It is closely related to other units such as the chain (which is 4 rods) and the furlong (which is 40 rods).
Key conversions:
1 rod = 16.5 feet
1 rod = 5.5 yards
1 rod = 5.0292 meters
4 rods = 1 chain
40 rods = 1 furlong
Though largely replaced by metric units today, the rod is still occasionally used in surveying and legal descriptions of land, especially in the United States and the UK.
No conversions available for length.