Global Earthquakes in Realtime using Firebase Open Data Sets

earthquakes.js

const CONTINENTS = ["europe", "asia", "africa", "north_america", "south_america", "antartica", "oceanic"];
var map;
var previousInfowindow;
var ref = new Firebase("https://publicdata-earthquakes.firebaseio.com/by_continent/");
 
function mapQuake(snapshot) {
    var quake = snapshot.val();
    var myLatlng = new google.maps.LatLng(quake.location.lat,quake.location.lng);
    map.setCenter(myLatlng);
 
    var marker = new google.maps.Marker({
        position: myLatlng,
        map: map,
        animation: google.maps.Animation.DROP,
    });  
    
    google.maps.event.addListener(marker, 'click', function() {
        infowindow = new google.maps.InfoWindow({
            content: '<b>Magnitude: </b>' + quake.mag + '<br /><b>Where:</b> '+ quake.place + '<br /><b>When: </b>' + (new Date(quake.time)) 
        }); 
 
        if (previousInfowindow) {
            previousInfowindow.close();
        }
        infowindow.open(map,marker);
        previousInfowindow = infowindow;
    });
}
 
function start() {
    map = new google.maps.Map(document.getElementById('map_canvas'), {zoom: 3});
    
    for (var con=0; con<CONTINENTS.length; con++) {
        var continent = CONTINENTS[con];
        for (var mag=0; mag<10; mag++) {
            var magRef = ref.child(continent).child(mag.toString());
            magRef.orderByKey().limitToLast(3).on("child_added", mapQuake);
        }
    }
}
 
$(start);