Unit: US survey foot
Data source: EPSG
Information source: USGS Professional Paper #1395.
Revision date: 1995-06-02
Remarks: Used for Michigan NAD27 State Plane zones. Radius = ellipsoid radius + 800 feet; this approximates the average elevation of the state. Derived parameter: 1/f = 294.97870
Definition: OGC Well Known Text
SPHEROID["Clarke 1866 Michigan",6378450.0475489,294.978697164677, AUTHORITY["EPSG","7009"]]
Definition: OGC Well Known Text 2 (2019)
ELLIPSOID["Clarke 1866 Michigan",20926631.531,294.978697164677, LENGTHUNIT["US survey foot",0.304800609601219], ID["EPSG",7009]]
Definition: ESRI Well Known Text
SPHEROID["Clarke_1866_Michigan",6378450.0475489,294.978697164677]
Definition: JSON
{ "$schema": "https://proj.org/schemas/v0.5/projjson.schema.json", "type": "Ellipsoid", "name": "Clarke 1866 Michigan", "semi_major_axis": { "value": 20926631.531, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 } }, "semi_minor_axis": { "value": 20855688.674, "unit": { "type": "LinearUnit", "name": "US survey foot", "conversion_factor": 0.304800609601219 } }, "id": { "authority": "EPSG", "code": 7009 } }