diff --git a/Astro/moon.h b/Astro/moon.h
index f43820ae..ff7b2107 100644
--- a/Astro/moon.h
+++ b/Astro/moon.h
@@ -26,6 +26,11 @@
 #define _MOON_H
 
 
+#ifdef __cplusplus                                                          
+extern "C" {                            
+#endif                                   
+
+
 #include <Astro/orbits.h>
 
 #include <Time/fg_time.h>
@@ -44,15 +49,24 @@ struct CelestialCoord fgCalculateMoon(struct OrbElements Params,
 
 extern struct OrbElements pltOrbElements[9];
 
+
+#ifdef __cplusplus
+}
+#endif
+
+
 #endif /* _MOON_H */
 
 
 /* $Log$
-/* Revision 1.6  1998/02/23 19:07:54  curt
-/* Incorporated Durk's Astro/ tweaks.  Includes unifying the sun position
-/* calculation code between sun display, and other FG sections that use this
-/* for things like lighting.
+/* Revision 1.7  1998/04/21 17:02:30  curt
+/* Prepairing for C++ integration.
 /*
+ * Revision 1.6  1998/02/23 19:07:54  curt
+ * Incorporated Durk's Astro/ tweaks.  Includes unifying the sun position
+ * calculation code between sun display, and other FG sections that use this
+ * for things like lighting.
+ *
  * Revision 1.5  1998/02/02 20:53:21  curt
  * To version 0.29
  *
diff --git a/Astro/orbits.h b/Astro/orbits.h
index 377c4166..ab94bea5 100644
--- a/Astro/orbits.h
+++ b/Astro/orbits.h
@@ -27,6 +27,11 @@
 #define _ORBITS_H
 
 
+#ifdef __cplusplus                                                          
+extern "C" {                            
+#endif                                   
+
+
 #include <stdio.h>
 #include <math.h>
 
@@ -79,15 +84,23 @@ int  fgSolarSystemInit(struct fgTIME t);
 void fgSolarSystemUpdate(struct OrbElements *planets, struct fgTIME t);
 
 
+#ifdef __cplusplus
+}
+#endif
+
+
 #endif /* _ORBITS_H */
 
 
 /* $Log$
-/* Revision 1.6  1998/02/23 19:07:55  curt
-/* Incorporated Durk's Astro/ tweaks.  Includes unifying the sun position
-/* calculation code between sun display, and other FG sections that use this
-/* for things like lighting.
+/* Revision 1.7  1998/04/21 17:02:31  curt
+/* Prepairing for C++ integration.
 /*
+ * Revision 1.6  1998/02/23 19:07:55  curt
+ * Incorporated Durk's Astro/ tweaks.  Includes unifying the sun position
+ * calculation code between sun display, and other FG sections that use this
+ * for things like lighting.
+ *
  * Revision 1.5  1998/02/12 21:59:35  curt
  * Incorporated code changes contributed by Charlie Hotchkiss
  * <chotchkiss@namg.us.anritsu.com>
diff --git a/Astro/planets.h b/Astro/planets.h
index bdd1d7b5..8c147ff4 100644
--- a/Astro/planets.h
+++ b/Astro/planets.h
@@ -27,6 +27,11 @@
 #define _PLANETS_H
 
 
+#ifdef __cplusplus                                                          
+extern "C" {                            
+#endif                                   
+
+
 struct CelestialCoord fgCalculatePlanet(struct OrbElements planet,
                                          struct OrbElements theSun,
                                          struct fgTIME t, int idx);
@@ -36,14 +41,22 @@ void fgPlanetsInit( void );
 void fgPlanetsRender( void );
 
 
+#ifdef __cplusplus
+}
+#endif
+
+
 #endif /* PLANETS_H */
 
 
 /* $Log$
-/* Revision 1.4  1998/02/12 21:59:38  curt
-/* Incorporated code changes contributed by Charlie Hotchkiss
-/* <chotchkiss@namg.us.anritsu.com>
+/* Revision 1.5  1998/04/21 17:02:31  curt
+/* Prepairing for C++ integration.
 /*
+ * Revision 1.4  1998/02/12 21:59:38  curt
+ * Incorporated code changes contributed by Charlie Hotchkiss
+ * <chotchkiss@namg.us.anritsu.com>
+ *
  * Revision 1.3  1998/02/02 20:53:23  curt
  * To version 0.29
  *
diff --git a/Astro/sky.h b/Astro/sky.h
index 7e1275dd..06569863 100644
--- a/Astro/sky.h
+++ b/Astro/sky.h
@@ -28,6 +28,11 @@
 #define _SKY_H
 
 
+#ifdef __cplusplus                                                          
+extern "C" {                            
+#endif                                   
+
+
 /* (Re)generate the display list */
 void fgSkyInit( void );
 
@@ -38,13 +43,21 @@ void fgSkyColorsInit( void );
 void fgSkyRender( void );
 
 
+#ifdef __cplusplus
+}
+#endif
+
+
 #endif /* _SKY_H */
 
 
 /* $Log$
-/* Revision 1.3  1998/01/22 02:59:28  curt
-/* Changed #ifdef FILE_H to #ifdef _FILE_H
+/* Revision 1.4  1998/04/21 17:02:32  curt
+/* Prepairing for C++ integration.
 /*
+ * Revision 1.3  1998/01/22 02:59:28  curt
+ * Changed #ifdef FILE_H to #ifdef _FILE_H
+ *
  * Revision 1.2  1998/01/19 18:40:17  curt
  * Tons of little changes to clean up the code and to remove fatal errors
  * when building with the c++ compiler.
diff --git a/Astro/stars.h b/Astro/stars.h
index b56934cc..c4247ab3 100644
--- a/Astro/stars.h
+++ b/Astro/stars.h
@@ -28,6 +28,11 @@
 #define _STARS_H
 
 
+#ifdef __cplusplus                                                          
+extern "C" {                            
+#endif                                   
+
+
 #define FG_MAX_STARS 500
 #define FG_STAR_LEVELS 4         /* how many star transitions */
 #define FG_MIN_STAR_MAG 0.738750 /* magnitude of weakest star we'll display */
@@ -40,14 +45,23 @@ void fgStarsRender( void );
 extern struct OrbElements pltOrbElements[9];
 extern struct fgTIME cur_time_params;
 
+
+#ifdef __cplusplus
+}
+#endif
+
+
 #endif /* _STARS_H */
 
 
 /* $Log$
-/* Revision 1.4  1998/02/12 21:59:39  curt
-/* Incorporated code changes contributed by Charlie Hotchkiss
-/* <chotchkiss@namg.us.anritsu.com>
+/* Revision 1.5  1998/04/21 17:02:33  curt
+/* Prepairing for C++ integration.
 /*
+ * Revision 1.4  1998/02/12 21:59:39  curt
+ * Incorporated code changes contributed by Charlie Hotchkiss
+ * <chotchkiss@namg.us.anritsu.com>
+ *
  * Revision 1.3  1998/01/22 02:59:28  curt
  * Changed #ifdef FILE_H to #ifdef _FILE_H
  *
diff --git a/Astro/sun.h b/Astro/sun.h
index b37a7934..b9f6f0b0 100644
--- a/Astro/sun.h
+++ b/Astro/sun.h
@@ -27,6 +27,11 @@
 #define _SUN_H
 
 
+#ifdef __cplusplus                                                          
+extern "C" {                            
+#endif                                   
+
+
 extern fgSUNPOS solarPosition;
 
 
@@ -40,13 +45,21 @@ void fgSunInit( void );
 void fgSunRender( void );
 
 
+#ifdef __cplusplus
+}
+#endif
+
+
 #endif /* _SUN_H */
 
 
 /* $Log$
-/* Revision 1.5  1998/03/09 22:47:26  curt
-/* Incorporated Durk's updates.
+/* Revision 1.6  1998/04/21 17:02:33  curt
+/* Prepairing for C++ integration.
 /*
+ * Revision 1.5  1998/03/09 22:47:26  curt
+ * Incorporated Durk's updates.
+ *
  * Revision 1.4  1998/02/23 19:07:57  curt
  * Incorporated Durk's Astro/ tweaks.  Includes unifying the sun position
  * calculation code between sun display, and other FG sections that use this