diff --git a/pyatmos/msise/spaceweather.py b/pyatmos/msise/spaceweather.py
index 034dcf2..809e054 100644
--- a/pyatmos/msise/spaceweather.py
+++ b/pyatmos/msise/spaceweather.py
@@ -6,7 +6,7 @@
 
 from ..utils.try_download import wget_download
 
-def download_sw_nrlmsise00(direc=None):
+def download_sw_nrlmsise00(direc=None, url = 'https://celestrak.com/spacedata/SW-All.csv'):
     '''
     Download or update the space weather data from www.celestrak.com
 
@@ -29,7 +29,7 @@ def download_sw_nrlmsise00(direc=None):
         direc = home + '/src/sw-data/'
     
     swfile = direc + 'SW-All.csv'
-    url = 'https://www.celestrak.com/SpaceData/SW-All.csv'
+    
 
     if not path.exists(direc): makedirs(direc)
     if not path.exists(swfile):
@@ -104,7 +104,7 @@ def get_sw(sw_df,t_ymd,hour):
     f107A,f107,ap = sw_df.iloc[j]['F10.7_OBS_CENTER81'],sw_df.iloc[j+1]['F10.7_OBS'],sw_df.iloc[j]['AP_AVG']
     aph_tmp_b0 = sw_df.iloc[j]['AP1':'AP8']   
     i = int(np.floor_divide(hour,3))
-    ap_c = aph_tmp_b0[i]
+    ap_c = aph_tmp_b0[f'AP{i+1}']
     aph_tmp_b1 = sw_df.iloc[j+1]['AP1':'AP8']
     aph_tmp_b2 = sw_df.iloc[j+2]['AP1':'AP8']
     aph_tmp_b3 = sw_df.iloc[j+3]['AP1':'AP8']
@@ -114,4 +114,4 @@ def get_sw(sw_df,t_ymd,hour):
     aph_1233 = np.average(aph_tmp[apc_index+4:apc_index+12])
     aph_3657 = np.average(aph_tmp[apc_index+12:apc_index+20])
     aph = np.hstack((ap,aph_c369,aph_1233,aph_3657))
-    return f107A,f107,ap,aph
\ No newline at end of file
+    return f107A,f107,ap,aph