Convert Chain (US Survey) (ch (US)) to Megameter (Mm) instantly.
About these units
Chain (US Survey) (ch (US))
The US Survey Chain is defined as 66 US Survey Feet (~20.1168 meters), aligning with the historic Gunter's chain but adapted to the US survey foot. It is used primarily in cadastral surveys, property delineation, and historical land records. Surveyors employ the chain for practical measurements of fields, lots, and infrastructure layouts. The unit's subdivision into 100 links simplifies area calculation, as 10 square chains equal one acre, maintaining continuity with older surveying systems. Even today, engineers and surveyors working with legacy data encounter the US survey chain in historical deeds, maps, and legal descriptions. Its precision ensures consistency when reconciling pre-modern measurements with modern coordinates.
Megameter (Mm)
The megameter, measuring one million meters (1,000 kilometers), is useful for describing large geographical or geophysical distances on planetary scales. Earth's radius (approximately 6.37 Mm) and the thickness of atmospheric layers can be expressed effectively in megameters. This unit provides a clean and compact way to represent massive distances without resorting to scientific notation. The megameter also appears in discussions of communication signals, satellite orbits, and especially planetary science. While kilometers are still more common in public-facing contexts, megameters offer a more mathematically elegant representation for large calculations. They provide a middle ground between human-scale geography and astronomical units.