Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 8 15.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 08/15/2021   10:40:42   (   0.05,-137.20) (  -0.28,-135.66)  175.54                80
 08/16/2021   23:02:18   (  -0.05,-137.19) (  -0.89,-140.87)  419.22                80
 08/17/2021   22:46:00   (  -0.04,-137.19) (   0.17,-136.28)  103.27                80
 08/19/2021   11:07:27   (   0.04,-137.18) (   1.01,-141.45)  487.49                80
 08/20/2021   10:45:50   (   0.03,-137.17) (  -0.05,-136.87)   34.65                80
 08/22/2021   22:48:27   (  -0.02,-137.14) (  -0.12,-137.48)   39.29                80
 08/23/2021   22:32:09   (  -0.01,-137.13) (   0.94,-132.90)  483.01                80
 08/25/2021   10:50:57   (   0.01,-137.12) (   0.24,-138.07)  108.06                80
 08/26/2021   10:34:39   (   0.02,-137.11) (  -0.82,-133.48)  413.97                80
 08/27/2021   22:53:33   (  -0.01,-137.08) (  -0.40,-138.68)  182.36                80
 08/28/2021   22:37:16   (  -0.01,-137.07) (   0.66,-134.10)  339.28                80