draw point in some distance betwen two geo points lat/lon

leaflet-custom-markers.js

    _calculateOffset: function(bearing_angle, radius){
        //Calculate destination point based on bearing and distance
        //http://www.movable-type.co.uk/scripts/latlong.html
        var d2r = L.LatLng.DEG_TO_RAD; //simple convert do radians
        var r2d= L.LatLng.RAD_TO_DEG;  //simple convert to degrees
        var radius = radius/1500;
        var lat = this._latlng.lat * d2r;
        var lng = this._latlng.lng * d2r;
        var angle = bearing_angle * d2r;
        var R = 6372.795477598;
        var distance = (radius/R);

        var lat2 = Math.asin( Math.sin(lat)*Math.cos(distance) +
                                Math.cos(lat)*Math.sin(distance) * Math.cos(angle));

        var lon2 = lng + Math.atan2(Math.sin(angle)*Math.sin(distance)*Math.cos(lat),
             Math.cos(distance)-Math.sin(lat)*Math.sin(lat2));

        return new L.latLng(lat2 * r2d,lon2 * r2d);
    },