diff --git a/ship.py b/ship.py
index 42ce1d7..a3e864a 100644
--- a/ship.py
+++ b/ship.py
@@ -21,4 +21,5 @@ class Ship(Sprite):
 
         # 在飞船的属性center中存储小数值
         self.center = float(self.rect.centerx)
+        self.centery = float(self.rect.centery)