Definition
- $centerSphere
- Defines a circle for a geospatial query that uses spherical geometry. The query returns documents that are within the bounds of the circle. You can use the - $centerSphereoperator on both GeoJSON objects and legacy coordinate pairs.- To use - $centerSphere, specify an array that contains:- The grid coordinates of the circle's center point, and 
- The circle's radius measured in radians. To calculate radians, see Convert Distance to Radians for Spherical Operators. 
 - { - <location field>: { - $geoWithin: { $centerSphere: [ [ <x>, <y> ], <radius> ] } - } - } - Important- If you use longitude and latitude, specify longitude first.
Behavior
Applications can use $centerSphere without having a geospatial index.
However, geospatial indexes support much faster queries than the
unindexed equivalents.
Both 2dsphere and 2d
geospatial indexes support $centerSphere.
Example
The following example queries grid coordinates and returns all
documents within a 10 mile radius of longitude 88 W and latitude
30 N. The query converts the distance to radians by dividing by the
approximate equatorial radius of the earth, 3963.2 miles:
db.places.find( {   loc: { $geoWithin: { $centerSphere: [ [ -88, 30 ], 10/3963.2 ] } } } )