# Rods to Astronomical Units (rd to au) Source: https://www.unitconvertercalculator.com/length/rods-to-astronomical-units/ **1 rd = 3.3618125555312E-11 au** One rod equals approximately 3.361 x 10-11 astronomical units. The Earth-Sun distance (1 AU) is about 29.76 billion rods. The rod measures English farmland; the AU measures planetary orbits. ## Formula Convert Rods to Astronomical Units ## Conversion Table | Rods (rd) | Astronomical Units (au) | |---|---| | 1 rd | 3.361812555E-11 au | | 10 rd | 3.3618125555E-10 au | | 100 rd | 3.36181255553E-9 au | | 1000 rd | 3.361812555531E-8 au | | 10000 rd | 3.3618125555312E-7 au | | 100000 rd | 3.3618125555312E-6 au | | 1000000 rd | 3.3618125555312E-5 au | | 10000000 rd | 0.00033618125555312 au | | 100000000 rd | 0.0033618125555312 au | ## Units ### Rod (rd) Exactly 16.5 feet or 5.5 yards (5.0292 m). Also called a perch or pole. Historically used in land surveying. ### Astronomical Unit (au) Exactly 149,597,870,700 meters by IAU 2012 definition. Roughly the average distance from the Earth to the Sun. Used for distances within our solar system. ## Background 1 AU = 29.76 billion rods. A 10-acre field (10 square chains = 40 x 100 rods) is vanishingly small compared to planetary distances. The rod was designed for fields; the AU for orbits. ## Good to Know The rod measured the fields that fed medieval communities. The AU measures the orbit that warms those fields. One is human-scale agriculture; the other is planetary-scale astronomy. Both describe the relationship between the Sun and food production, just at different levels of abstraction. ## FAQ ### How many AU is 1 rod? One rod equals approximately 3.361 x 10-11 AU. ### How many rods are in 1 AU? One AU contains approximately 2.976 x 1010 rods (about 29.76 billion). ### Is this conversion used? Never. Farmland and planetary orbits exist at completely different scales. ## Non-Frequently Asked Questions ### How many medieval fields fit between Earth and the Sun? A strip field was about 40 rods long. 1 AU = 29.76 billion rods = 744 million strip fields. If every field in medieval England (about 5 million strips) were placed end-to-end, they would span about 0.67% of the Earth-Sun distance. All English farmland reaches less than 1% of the way to the Sun. ### If a surveyor measured toward the Sun, when would they arrive? At 1 rod per minute: 29.76 billion minutes = 56,621 years. The surveyor would arrive around the year 58,647. The Sun might still be there. The surveyor would not. ### How many acres of solar system? An acre is 10 square chains = 4,047 m2. The area of a disc to Neptune's orbit (30 AU radius) is about 2.83 x 1025 m2 = about 7 x 1021 acres. The solar system is 7 sextillion acres of mostly empty space. Property taxes would be low. ## Related Articles - [Why We Measure: The Deepest Urge in Human Civilisation](https://www.unitconvertercalculator.com/blog/why-we-measure) - [The Map Is Not the Territory: Why Every Measurement Is Wrong](https://www.unitconvertercalculator.com/blog/the-map-is-not-the-territory) - [Zero: The Most Dangerous Number in Measurement](https://www.unitconvertercalculator.com/blog/zero-the-most-dangerous-number-in-measurement) - [The Body as a Ruler: Every Measurement Unit That Came From Us](https://www.unitconvertercalculator.com/blog/the-body-as-a-ruler) - [The Speed of Everything: How We Measure From Glaciers to Light](https://www.unitconvertercalculator.com/blog/the-speed-of-everything) - [15 Obscure Measurement Units You've Never Heard Of (But Still Need)](https://www.unitconvertercalculator.com/blog/obscure-measurement-units-guide) - [When Measurements Go Wrong - Disasters, Blunders and Happy Accidents](https://www.unitconvertercalculator.com/blog/when-measurements-go-wrong) - [The Surprising Stories Behind Everyday Units of Measurement](https://www.unitconvertercalculator.com/blog/stories-behind-measurement-units) - [Metric vs. Imperial - The Complete Guide to the World's Two Measurement Systems](https://www.unitconvertercalculator.com/blog/metric-vs-imperial-complete-guide) - [Length & Distance Conversion Guide - Meters, Feet, Miles & Kilometers](https://www.unitconvertercalculator.com/blog/length-and-distance-guide) ## See Also - [Astronomical Units to Rods](https://www.unitconvertercalculator.com/length/astronomical-units-to-rods/)