VOID_HUDAdvanced: NaN handling for burntime strvalues.
VOID_HUDAdvanced: NaN handling for burntime strvalues.

--- a/VOID_HUDAdvanced.cs
+++ b/VOID_HUDAdvanced.cs
@@ -590,6 +590,11 @@
 
 			double interval = (node.UT - currentNodeBurnDuration) - Planetarium.GetUniversalTime();
 
+			if (double.IsNaN(interval))
+			{
+				return string.Intern("NaN");
+			}
+
 			int sign = Math.Sign(interval);
 			interval = Math.Abs(interval);