diff --git a/common/system.py b/common/system.py
index 6fdf27365ba60733335b55dee453b216236ca1d4..48c024286a196857b28f4cff3909579d2dd50d15 100644
--- a/common/system.py
+++ b/common/system.py
@@ -177,7 +177,7 @@ class System(object):
         forces = G * disps * mass_matrix / np.expand_dims(dists, 2) ** 3
         return forces.sum(axis=1) / masses.reshape(-1, 1)
 
-    def calc_bodies_acceleration(self):
+    def calc_bodies_acceleration_bak(self):
         """
         计算加速度(使用矩阵的方式，性能提高很多)
         @return:
@@ -194,7 +194,7 @@ class System(object):
         for idx, body in enumerate(valid_bodies):
             body.acceleration = accelerations[idx]/1000
 
-    def calc_bodies_acceleration_bak(self):
+    def calc_bodies_acceleration(self):
         """
         计算加速度（性能非常低，代码保留）
         @return:
diff --git a/sim_scenes/science/jupiter_moon_protects_earth.py b/sim_scenes/science/jupiter_moon_protects_earth.py
index 327eb11f30c5ca24811538708017e59ca0d735a4..eaeaf15f6a31acd87380c69759145d20373c51ba 100644
--- a/sim_scenes/science/jupiter_moon_protects_earth.py
+++ b/sim_scenes/science/jupiter_moon_protects_earth.py
@@ -204,7 +204,7 @@ if __name__ == '__main__':
     # 设置计时器的最小时间单位为年
     BodyTimer().min_unit = BodyTimer.MIN_UNIT_YEARS
 
-    sim = JupiterProtectsEarthSim(comet_num=30)
+    sim = JupiterProtectsEarthSim(comet_num=20)
 
     # 运行前会触发 on_ready
     UrsinaEvent.on_ready_subscription(sim.on_ready)