diff --git a/punyverse/__main__.py b/punyverse/__main__.py
index 8c31774..fc4c679 100644
--- a/punyverse/__main__.py
+++ b/punyverse/__main__.py
@@ -3,13 +3,20 @@ INITIAL_WIN_HEIGHT = 540
 INITIAL_WIN_WIDTH = 700
 WIN_TITLE = "Punyverse"
 
+
 def main():
+    import argparse
+    parser = argparse.ArgumentParser(prog='punyverse', description='Python simulator of a puny universe.')
+    parser.add_argument('-t', '--ticks', help='Ticks per second for game, more means more responsive, but '
+                        ' may run slower, default is 20.', default=20, type=int)
+    args = parser.parse_args()
+
     import pyglet
-    from punyverse.game import Applet
-
+    from punyverse import game
     pyglet.options['shadow_window'] = False
+    game.TICKS_PER_SECOND = args.ticks
 
-    Applet(width=INITIAL_WIN_WIDTH, height=INITIAL_WIN_HEIGHT, caption=WIN_TITLE, resizable=True, vsync=0)
+    game.Applet(width=INITIAL_WIN_WIDTH, height=INITIAL_WIN_HEIGHT, caption=WIN_TITLE, resizable=True, vsync=0)
     pyglet.app.run()
 
 
diff --git a/punyverse/game.py b/punyverse/game.py
index a4a8433..3f2c56d 100644
--- a/punyverse/game.py
+++ b/punyverse/game.py
@@ -47,10 +47,10 @@ class Applet(pyglet.window.Window):
             if key.S in self.keys:
                 cam.roll -= 4
             if self.moving:
-                cam.move(self.speed)
+                cam.move(int(self.speed * dt * TICKS_PER_SECOND + 0.5))
 
         if self.running:
-            self.world.tick += self.tick
+            self.world.tick += int(self.tick * dt * TICKS_PER_SECOND + 0.5)
             for entity in self.world.tracker:
                 entity.update()
 
@@ -73,8 +73,8 @@ class Applet(pyglet.window.Window):
         self.atmosphere = True
         self.cloud = not texture.badcard
 
-        self.tick = self.world.tick_length
-        self.ticks = [20, 40, 60,                             # Second range
+        self.tick = self.world.tick_length / TICKS_PER_SECOND
+        self.ticks = [1, 2, 5, 10, 20, 40, 60,                # Second range
                       120, 300, 600, 1200, 1800, 2700, 3600,  # Minute range
                       7200, 14400, 21600, 43200, 86400,       # Hour range
                       172800, 432000, 604800,                 # 2, 5, 7 days
@@ -83,7 +83,8 @@ class Applet(pyglet.window.Window):
                       63072000, 157680000, 315360000,         # 2, 5, 10 years
                       630720000, 1576800000, 3153600000,      # 20, 50, 100 years
         ]
-        self.ticks = [i / 20 for i in self.ticks]
+        self.ticks = [i / TICKS_PER_SECOND for i in self.ticks]
+        self.ticks = sorted(set(i for i in self.ticks if i))
         self.__time_per_second_cache = None
         self.__time_per_second_value = None
 
diff --git a/punyverse/world.json b/punyverse/world.json
index 84ed40f..9178e08 100644
--- a/punyverse/world.json
+++ b/punyverse/world.json
@@ -11,7 +11,7 @@
     "model": "used to load a wavefront object instead of a textured sphere"
   },
   "au": 10000,
-  "tick": 180,
+  "tick": 3600,
   "length": 63.7,
   "bodies": {
     "sun": {