Simultaneous Nadir Overpasses (SNOs) between FY3D and NPP
TLE Epoch: 2021 4 26.  Predictions up to the next  14.0 days:

     Date     Time(FY3D) FY3D Lat/Lon Date Time(NPP) NPP Lat/Lon    Distance(km)  Time Diff(sec)
 05/09/2021   17:11:50   ( -81.21,  42.09) 05/09/2021   17:10:35  ( -81.22,  42.06)    0.63                75
 05/09/2021   18:02:35   (  81.22,-150.76) 05/09/2021   18:01:20  (  81.22,-150.78)    0.45                75
 05/09/2021   18:53:19   ( -81.22,  16.71) 05/09/2021   18:52:05  ( -81.22,  16.63)    1.34                74
 05/09/2021   19:44:04   (  81.22,-176.15) 05/09/2021   19:42:50  (  81.22,-176.21)    1.17                74
 05/09/2021   20:34:48   ( -81.22,  -8.68) 05/09/2021   20:33:35  ( -81.22,  -8.80)    2.05                73
 05/09/2021   21:25:33   (  81.22, 158.47) 05/09/2021   21:24:20  (  81.22, 158.36)    1.89                73
 05/09/2021   22:16:17   ( -81.22, -34.07) 05/09/2021   22:15:05  ( -81.22, -34.23)    2.76                72
 05/09/2021   23:07:01   (  81.21, 133.47) 05/09/2021   23:05:49  (  81.21, 133.31)    2.61                72
 05/09/2021   23:57:46   ( -81.22, -59.46) 05/09/2021   23:56:34  ( -81.21, -59.28)    3.13                72
 05/10/2021   00:48:31   (  81.22, 107.69) 05/10/2021   00:47:19  (  81.22, 107.88)    3.28                72
 05/10/2021   01:39:15   ( -81.22, -84.85) 05/10/2021   01:38:04  ( -81.21, -84.70)    2.42                71
 05/10/2021   02:29:59   (  81.22,  82.30) 05/10/2021   02:28:48  (  81.22,  82.45)    2.56                71