getBoundingBox( target ) {

		if ( this.isEmpty() ) {

			// Empty sphere produces empty bounding box
			target.makeEmpty();
			return target;

		}

		target.set( this.center, this.center );
		target.expandByScalar( this.radius );

		return target;

	}
Returns a bounding box that encloses this sphere.

@param {Box3} target - The target box that is used to store the method's result.
@return {Box3} The bounding box that encloses this sphere.