Index: /trunk/FACT++/src/scheduler.cc
===================================================================
--- /trunk/FACT++/src/scheduler.cc	(revision 19657)
+++ /trunk/FACT++/src/scheduler.cc	(revision 19658)
@@ -1054,18 +1054,26 @@
         // night (above the required horizon) or is circumpolar
         // above that horizon
-        //
-        // Considtions are:
-        // ((Rises      after sun-rise or before sun-set) and
-        //  (Culminates after sun-rise or before sun-set) and
-        //  (Sets       after sun-rise or before sun-set) and
-        //  (object not circumpolar/rise-trans-set valid))
-        // or is circumpolar below the defined horizon
-        //
-        if (check.vis_obj==-1 ||
-            (check.vis_obj==0 &&
-             (rise <sun_set || rise >sun_rise) &&
-             (trans<sun_set || trans>sun_rise) &&
-             (set  <sun_set || set  >sun_rise)))
+        switch (check.vis_obj)
+        {
+        case -1:
+            // Object is not visible above the requested horizon
             return;
+
+        case 0:
+            // Object crosses the local meridian
+            //  Rises      after sun-rise or before sun-set
+            //  Culminates after sun-rise or before sun-set
+            //  Sets       after sun-rise or before sun-set
+            if ((rise <sun_set || rise >sun_rise) &&
+                (trans<sun_set || trans>sun_rise) &&
+                (set  <sun_set || set  >sun_rise))
+                return;
+
+            break;
+
+        case 1:
+            // Object is always visible above the requested horizon
+            break;
+        }
 
         Info("Source "+name+" might be observable.");