diff --git a/index.html b/index.html
index 7eea6e5..20a3535 100644
--- a/index.html
+++ b/index.html
@@ -76,6 +76,7 @@
 <body>
     <div id="vanta"></div>
     <div id="info-panel">
+        <div id="debug" style="font-size:10px;color:#999187;"></div>
         <svg id="analog-clock" viewBox="0 0 200 200">
             <!-- Clock face -->
             <circle cx="100" cy="100" r="95" fill="rgba(28,27,31,0.3)" stroke="#e6dfd1" stroke-width="2"/>
@@ -569,6 +570,11 @@
                 getMoonPhaseText(moonIllum.phase) + ' ' + Math.round(moonIllum.fraction * 100) + '%';
             renderMoonPhaseIcon(moonIllum.phase);
             renderRpgMoon(moonIllum.phase);
+
+            document.getElementById('debug').textContent =
+                'rpg-moon exists: ' + (rpgMoon !== null) +
+                ' | lit: ' + (rpgMoonLit !== null) +
+                ' | moonPos: ' + (moonPos ? Math.round(moonPos.point.x) + ',' + Math.round(moonPos.point.y) : 'null');
         }
 
         var startTime = Date.now();