diff --git a/planetstack/templates/admin/base.html b/planetstack/templates/admin/base.html
index 29823a5..5b355d9 100644
--- a/planetstack/templates/admin/base.html
+++ b/planetstack/templates/admin/base.html
@@ -29,6 +29,10 @@
 
 <body class="{% if is_popup %}popup {% endif %}{% block bodyclass %}{% endblock %}">
 
+<div id="dialog-placeholder">
+<!-- This is a placeholder for dialog boxes, like the observer calendar -->
+</div>
+
 <!-- Sticky footer wrap -->
 <div id="wrap">