diff --git a/dat/ssys.xml b/dat/ssys.xml
index e385982..0dec2da 100644
--- a/dat/ssys.xml
+++ b/dat/ssys.xml
@@ -32,7 +32,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>50</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>500</stars>
   </general>
@@ -57,11 +57,11 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>50</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>160</stars>
   </general>
- </ssys>
+</ssys>
  <ssys name="Raelid">
   <fleets>
    <fleet chance="60">Draktharr Vendetta</fleet>
@@ -92,7 +92,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>100</interference>
    <nebulae volatility="0">100</nebulae>
    <stars>500</stars>
   </general>
@@ -119,7 +119,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>250</interference>
    <nebulae volatility="0">250</nebulae>
    <stars>400</stars>
   </general>
@@ -142,7 +142,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>600</interference>
    <nebulae volatility="100">600</nebulae>
    <stars>500</stars>
   </general>
@@ -257,7 +257,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>100</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>120</stars>
   </general>
@@ -310,7 +310,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>150</interference>
    <nebulae volatility="0">150</nebulae>
    <stars>400</stars>
   </general>
@@ -354,7 +354,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>400</interference>
    <nebulae volatility="0">400</nebulae>
    <stars>400</stars>
   </general>
@@ -432,7 +432,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>700</interference>
    <nebulae volatility="250">750</nebulae>
    <stars>500</stars>
   </general>
@@ -475,7 +475,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>300</interference>
    <nebulae volatility="0">250</nebulae>
    <stars>400</stars>
   </general>
@@ -552,7 +552,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>200</interference>
    <nebulae volatility="0">200</nebulae>
    <stars>500</stars>
   </general>
@@ -617,7 +617,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>50</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>400</stars>
   </general>
@@ -656,7 +656,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>100</interference>
    <nebulae volatility="0">100</nebulae>
    <stars>600</stars>
   </general>
@@ -675,7 +675,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>800</interference>
    <nebulae volatility="300">800</nebulae>
    <stars>400</stars>
   </general>
@@ -720,7 +720,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>300</interference>
    <nebulae volatility="0">200</nebulae>
    <stars>300</stars>
   </general>
@@ -843,7 +843,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>100</interference>
    <nebulae volatility="0">100</nebulae>
    <stars>500</stars>
   </general>
@@ -886,7 +886,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>450</interference>
    <nebulae volatility="50">500</nebulae>
    <stars>400</stars>
   </general>
@@ -916,7 +916,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>100</interference>
    <nebulae volatility="0">100</nebulae>
    <stars>600</stars>
   </general>
@@ -935,7 +935,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>350</interference>
    <nebulae volatility="0">300</nebulae>
    <stars>400</stars>
   </general>
@@ -1050,7 +1050,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>500</interference>
    <nebulae volatility="100">500</nebulae>
    <stars>400</stars>
   </general>
@@ -1070,7 +1070,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>650</interference>
    <nebulae volatility="150">700</nebulae>
    <stars>400</stars>
   </general>
@@ -1101,7 +1101,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>200</interference>
    <nebulae volatility="0">150</nebulae>
    <stars>500</stars>
   </general>
@@ -1181,7 +1181,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>300</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>100</stars>
   </general>
@@ -1199,7 +1199,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>800</interference>
    <nebulae volatility="400">800</nebulae>
    <stars>400</stars>
   </general>
@@ -1244,7 +1244,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>350</interference>
    <nebulae volatility="0">300</nebulae>
    <stars>400</stars>
   </general>
@@ -1278,7 +1278,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>50</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>400</stars>
   </general>
@@ -1297,7 +1297,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>950</interference>
    <nebulae volatility="500">900</nebulae>
    <stars>500</stars>
   </general>
@@ -1318,7 +1318,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>50</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>140</stars>
   </general>
@@ -1352,7 +1352,7 @@
   </planets>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>50</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>500</stars>
   </general>
@@ -1476,7 +1476,7 @@
   <planets/>
   <general>
    <asteroids>0</asteroids>
-   <interference>0</interference>
+   <interference>50</interference>
    <nebulae volatility="0">0</nebulae>
    <stars>500</stars>
   </general>
@@ -1517,4 +1517,4 @@
    <stars>500</stars>
   </general>
  </ssys>
-</Systems>
\ No newline at end of file
+</Systems>
diff --git a/src/player.c b/src/player.c
index eddaa7c..dffccf6 100644
--- a/src/player.c
+++ b/src/player.c
@@ -96,7 +96,7 @@ static unsigned int player_timer = 0;   /**< For death and such. */
 static Vec2 player_cam;                 /**< Again, for death etc. */
 /* For interference. */
 static int interference_layer    = 0;   /**< Layer of the current interference. */
-static double interference_alpha = 0.;  /**< Alpha of the current interference layer. */
+double interference_alpha = 0.;         /**< Alpha of the current interference layer. */
 static double interference_t     = 0.;  /**< Interference timer to control transitions. */
 
 static int* missions_done = NULL; /**< Saves position of completed missions. */
diff --git a/src/space.c b/src/space.c
index 635ac2d..2664716 100644
--- a/src/space.c
+++ b/src/space.c
@@ -78,6 +78,11 @@ static Star* stars = NULL;  /* Star array. */
 static int nstars = 0;      /* Total stars. */
 static int mstars = 0;      /* Memory stars are taking. */
 
+/* Interference. */
+extern double interference_alpha;       /* player.c */
+static double interference_target;      /**< Target alpha level .*/
+static double interference_timer = 0.;  /**< Interference timer. */
+
 extern int planet_target;   /* player.c */
 
 /* Intern. */
@@ -96,7 +101,7 @@ static PlanetClass planetclass_get(const char a);
 extern void player_message(const char* fmt, ...);
 
 void planets_minimap(const double res, const double w,
-    const double h, const RadarShape shape);
+    const double h, const RadarShape shape, double alpha);
 int space_sysSave(xmlTextWriterPtr writer);
 int space_sysLoad(xmlNodePtr parent);
 
@@ -105,7 +110,7 @@ int space_sysLoad(xmlNodePtr parent);
 #define PIXEL(x,y)  if((shape == RADAR_RECT && ABS(x)<w/2. && ABS(y)<h/2.) || \
   (shape == RADAR_CIRCLE && (((x)*(x)+(y)*(y)) <= rc))) glVertex2i((x),(y))
 void planets_minimap(const double res, const double w,
-    const double h, const RadarShape shape) {
+    const double h, const RadarShape shape, double alpha) {
   int i;
   int cx, cy, x, y, r, rc;
   double p;
@@ -124,7 +129,7 @@ void planets_minimap(const double res, const double w,
       col = &cRadar_tPlanet;
     else if((col != &cHostile) && !planet_hasService(planet, PLANET_SERVICE_BASIC))
       col = &cInert;  /* Override non-hostile planets without services. */
-    COLOUR(*col);
+    ACOLOUR(*col, alpha);
 
     /* Some parameters. */
     r = (int)(cur_system->planets[i]->gfx_space->sw / res);
@@ -416,6 +421,7 @@ void space_update(const double dt) {
 
   if(cur_system == NULL) return; /* Can't update a null system. */
 
+  /* Spawning. */
   if(space_spawn) {
     spawn_timer -= dt;
 
@@ -444,6 +450,36 @@ void space_update(const double dt) {
       pilot_hit(player, NULL, 0, DAMAGE_TYPE_RADIATION,
           pow2(cur_system->nebu_volatility) / 500. * dt);
   }
+
+  /* Interference. */
+  if(cur_system->interference > 0.) {
+    /* Always dark. */
+    if(cur_system->interference >= 1000.)
+      interference_alpha = 1.;
+
+    /* Normal scenario. */
+    else {
+      interference_timer -= dt;
+      if(interference_timer < 0.) {
+        interference_timer += (1000. - cur_system->interference) / 1000. *
+          (3. + NormalInverse(0.25 + 0.95*RNGF()));
+        interference_target = cur_system->interference/1000. * 3. *
+          (1. + NormalInverse(0.25 + 0.95*RNGF()));
+      }
+
+      /* Head towards target. */
+      if(fabs(interference_alpha - interference_target) > 1e-05) {
+        /* Assymptotic. */
+        interference_alpha += (interference_target - interference_alpha) * dt;
+
+        /* Limit alpha to [0. -1.]. */
+        if(interference_alpha > 1.)
+          interference_alpha = 1.;
+        else if(interference_alpha < 0.)
+          interference_alpha = 0.;
+      }
+    }
+  }
 }
 
 /**
@@ -551,6 +587,7 @@ void space_init(const char* sysname) {
   weapon_clear();   /* Get rid of all the weapons. */
   spfx_clear();     /* Remove of explosions. */
   space_spawn = 1;  /* Spawn is enabled by default. */
+  interference_timer = 0; /* Restart timer. */
 
   /* Clear player escorts since they don't automatically follow. */
   if(player) {
@@ -974,7 +1011,7 @@ static StarSystem* system_parse(StarSystem* sys, const xmlNodePtr parent) {
         }
         else if(xml_isNode(cur, "interference")) {
           flags |= FLAG_INTEFERENCESET;
-          sys->interference = xml_getFloat(cur)/100;
+          sys->interference = xml_getFloat(cur);
         }
         else if(xml_isNode(cur, "nebulae")) {
           ptrc = xml_nodeProp(cur, "volatility");
diff --git a/src/weapon.c b/src/weapon.c
index ad8aec9..c6c2cc7 100644
--- a/src/weapon.c
+++ b/src/weapon.c
@@ -106,7 +106,7 @@ static void think_seeker(Weapon* w, const double dt);
 static void think_beam(Weapon* w, const double dt);
 /* Extern. */
 void weapon_minimap(const double res, const double w,
-    const double h, const RadarShape shape);
+    const double h, const RadarShape shape, double alpha);
 
 /**
  * @fn void weapon_minimap(const double res, const double w,
@@ -123,13 +123,13 @@ void weapon_minimap(const double res, const double w,
     (shape == RADAR_CIRCLE && (((x)*(x)+(y)*(y)) <= rc))) \
     glVertex2i((x),(y)) /**< Set a pixel if within range. */
 void weapon_minimap(const double res, const double w,
-    const double h, const RadarShape shape) {
+    const double h, const RadarShape shape, double alpha) {
   int i, rc;
   double x, y;
 
   /* Begin the points. */
   glBegin(GL_POINTS);
-  COLOUR(cRadar_weap);
+  ACOLOUR(cRadar_weap, alpha);
 
   if(shape == RADAR_CIRCLE)
     rc = (int)(w*w);