Index: macosx/CelestiaAppCore.mm
===================================================================
--- macosx/CelestiaAppCore.mm	(revision 4157)
+++ macosx/CelestiaAppCore.mm	(working copy)
@@ -595,10 +595,13 @@
 
     case Selection::Type_Star:
         {
-            char name[32];
-            sprintf(name, "HIP%d", sel.star()->getCatalogNumber() & ~0xf0000000);
-
-            url = string("http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=") + name;
+            url = sel.star()->getInfoURL();
+            if (url.empty())
+            {
+                char name[32];
+                sprintf(name, "HIP%d", sel.star()->getCatalogNumber() & ~0xf0000000);                
+                url = string("http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=") + name;
+            }
         }
         break;
 
Index: src/celengine/star.h
===================================================================
--- src/celengine/star.h	(revision 4159)
+++ src/celengine/star.h	(working copy)
@@ -51,6 +51,7 @@
     inline bool getVisibility() const;
     inline const RotationModel* getRotationModel() const;
     inline Vec3f getEllipsoidSemiAxes() const;
+    const std::string& getInfoURL() const;
 
     void setRadius(float);
     void setTemperature(float);
@@ -65,6 +66,7 @@
     void setVisibility(bool);
     void setRotationModel(const RotationModel*);
     void setEllipsoidSemiAxes(const Vec3f&);
+    void setInfoURL(const std::string& _infoURL);
 
     bool shared() const;
     
@@ -101,6 +103,8 @@
 
     Vec3f semiAxes;
 
+    std::string* infoURL;
+    
     std::vector<Star*>* orbitingStars;
     bool isShared;
 
@@ -219,6 +223,7 @@
 }
 
 
+
 class Star
 {
 public:
@@ -267,6 +272,7 @@
     inline uint32 getKnowledge() const;
     inline const RotationModel* getRotationModel() const;
     inline Vec3f getEllipsoidSemiAxes() const;
+    const std::string& getInfoURL() const;
 
     enum {
         MaxTychoCatalogNumber = 0xf0000000,
Index: src/celengine/star.cpp
===================================================================
--- src/celengine/star.cpp	(revision 4159)
+++ src/celengine/star.cpp	(working copy)
@@ -43,6 +43,8 @@
 static StarDetails*  blackHoleDetails = NULL;
 static StarDetails*  barycenterDetails = NULL;
 
+static string DEFAULT_INFO_URL("");
+
 StarDetails::StarTextureSet StarDetails::starTextures;
 
 // Star temperature data from Lang's _Astrophysical Data: Planets and Stars_
@@ -748,6 +750,7 @@
     barycenter(NULL),
     rotationModel(NULL),
     semiAxes(1.0f, 1.0f, 1.0f),
+    infoURL(NULL),
     orbitingStars(NULL),
     isShared(true)
 {
@@ -768,20 +771,37 @@
     barycenter(sd.barycenter),
     rotationModel(sd.rotationModel),
     semiAxes(sd.semiAxes),
+    infoURL(NULL),
     orbitingStars(NULL),
     isShared(false)
 {
     assert(sd.isShared);
     memcpy(spectralType, sd.spectralType, sizeof(spectralType));
+    if (sd.infoURL != NULL)
+        infoURL = new string(*sd.infoURL);
 }
 
 
 StarDetails::~StarDetails()
 {
     delete orbitingStars;
+    delete infoURL;
 }
 
 
+/*! Return the InfoURL. If the InfoURL has not been set, this method
+ *  returns an empty string.
+ */
+const std::string&
+StarDetails::getInfoURL() const
+{
+    if (infoURL != NULL)
+        return *infoURL;
+    else
+        return DEFAULT_INFO_URL;
+}
+
+
 void
 StarDetails::setRadius(float _radius)
 {
@@ -893,7 +913,30 @@
 }
 
 
+/*! Set the InfoURL for this star.
+*/
+void
+StarDetails::setInfoURL(const string& _infoURL)
+{
+    if (_infoURL.empty())
+    {
+        // Save space in the common case--no InfoURL--by not
+        // allocating a string.
+        delete infoURL;
+        infoURL = NULL;
+    }
+    else
+    {
+        // Allocate the new string before freeing the old one, so we don't crash
+        // in the event the caller does something like:
+        // star->setInfoURL(star->getInfoURL());
+        string* oldURL = infoURL;
+        infoURL = new string(_infoURL);
+        delete oldURL;
+    }
+}
 
+
 Star::~Star()
 {
     // TODO: Implement reference counting for StarDetails objects so that
@@ -1056,6 +1099,16 @@
 }
 
 
+/*! Return the InfoURL. If the InfoURL has not been set, this method
+*  returns an empty string.
+*/
+const string&
+Star::getInfoURL() const
+{
+    return details->getInfoURL();
+}
+
+
 void Star::setCatalogNumber(uint32 n)
 {
     catalogNumber = n;
Index: src/celengine/stardb.cpp
===================================================================
--- src/celengine/stardb.cpp	(revision 4159)
+++ src/celengine/stardb.cpp	(working copy)
@@ -925,6 +925,9 @@
 
     double radius;
     bool hasRadius = starData->getNumber("Radius", radius);
+    
+    string infoURL;
+    bool hasInfoURL = starData->getString("InfoURL", infoURL);
 
     Orbit* orbit = CreateOrbit(NULL, starData, path, true);
 
@@ -933,7 +936,8 @@
         orbit != NULL   ||
         hasSemiAxes     ||
         hasRadius       ||
-        hasRotationModel)
+        hasRotationModel ||
+        hasInfoURL)
     {
         // If the star definition has extended information, clone the
         // star details so we can customize it without affecting other
@@ -961,6 +965,11 @@
             details->setRadius((float) radius);
             details->addKnowledge(StarDetails::KnowRadius);
         }
+        
+        if (hasInfoURL)
+        {
+            details->setInfoURL(infoURL);
+        }
 
         if (orbit != NULL)
         {
Index: src/celestia/winmain.cpp
===================================================================
--- src/celestia/winmain.cpp	(revision 4157)
+++ src/celestia/winmain.cpp	(working copy)
@@ -1731,10 +1731,13 @@
 
     case Selection::Type_Star:
         {
-            char name[32];
-            sprintf(name, "HIP%d", sel.star()->getCatalogNumber() & ~0xf0000000);
-
-            url = string("http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=") + name;
+            url = sel.star()->getInfoURL();
+            if (url.empty())
+            {
+                char name[32];
+                sprintf(name, "HIP%d", sel.star()->getCatalogNumber() & ~0xf0000000);
+                url = string("http://simbad.u-strasbg.fr/sim-id.pl?protocol=html&Ident=") + name;
+            }
         }
         break;