Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 8 9.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 08/09/2021   10:57:13   (   0.04,-137.20) (   0.48,-139.05)  211.49                80
 08/10/2021   10:35:36   (   0.04,-137.20) (  -0.58,-134.47)  311.59                80
 08/11/2021   22:57:11   (  -0.04,-137.20) (  -0.60,-139.67)  282.11                80
 08/12/2021   22:40:54   (  -0.04,-137.19) (   0.46,-135.09)  240.73                80
 08/14/2021   11:02:21   (   0.04,-137.18) (   0.72,-140.26)  350.46                80
 08/15/2021   10:40:42   (   0.04,-137.17) (  -0.28,-135.66)  171.74                80
 08/16/2021   23:02:18   (  -0.03,-137.16) (  -0.88,-140.87)  423.67                80
 08/17/2021   22:46:00   (  -0.03,-137.14) (   0.18,-136.29)   97.95                80
 08/19/2021   11:04:48   (   0.01,-137.12) (   1.01,-141.46)  495.22                80
 08/20/2021   10:48:30   (  -0.01,-137.10) (  -0.05,-136.87)   25.68                80
 08/22/2021   22:48:27   (   0.01,-137.06) (  -0.10,-137.49)   49.22                80