diff --git a/pyatmos/msise/nrlmsise00.py b/pyatmos/msise/nrlmsise00.py
index 15cd9ea..6c9b6ef 100644
--- a/pyatmos/msise/nrlmsise00.py
+++ b/pyatmos/msise/nrlmsise00.py
@@ -1051,7 +1051,7 @@ def nrlmsise00(t,location,SW_OBS_PRE,anmomode=True,aphmode=True):
 
     Parameters:
     anmomode -> [bool] whether to add anomalous oxygen component to the density; defalut = True
-    aphmode -> [bool] whether to use the 3h geomagnetic index, default = False
+    aphmode -> [bool] whether to use the 3h geomagnetic index, default = True
 
     Output:
     params -> [dict] parameters involved in computations, including Year, DayOfYear(DOY), SecondOfDay(SOD), 
@@ -1096,4 +1096,4 @@ def nrlmsise00(t,location,SW_OBS_PRE,anmomode=True,aphmode=True):
     rho = output['d']['RHO']          
     T = (output['t']['TINF'],output['t']['TG'])
     nd = {'He':output['d']['He'],'O':output['d']['O'],'N2':output['d']['N2'],'O2':output['d']['O2'],'Ar':output['d']['AR'],'H':output['d']['H'],'N':output['d']['N'],'ANM O':output['d']['ANM O']}
-    return params,rho,T,nd  
\ No newline at end of file
+    return params,rho,T,nd