var array = new Array(); // or the shortcut: = []
array.push ( {"cool":"34.33","also cool":"45454"} );
array.push ( {"cool":"34.39","also cool":"45459"} );
Your variable is a javascript object {} not an array [].
You could do:
var o = {}; // or the longer form: = new Object()
o.SomeNewProperty = "something";
o["SomeNewProperty"] = "something";
and
var o = { SomeNewProperty: "something" };
var o2 = { "SomeNewProperty": "something" };
Later, you add those objects to your array: array.push (o, o2);
Also JSON is simply a string representation of a javascript object, thus:
var json = '{"cool":"34.33","alsocool":"45454"}'; // is JSON
var o = JSON.parse(json); // is a javascript object
json = JSON.stringify(o); // is JSON again