get order data magento

$orders = Mage::getModel('sales/order')->getCollection();
foreach ($orders as $order){
$order->getIncrementId();
       $order['customer_firstname'];
        $order['customer_lastname'];
       $order['base_subtotal'];
        $order['grand_total'];
        $order['status'];
        $order['created_at'];
        $order['updated_at'];
    }