Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 4 22.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 04/23/2021   22:46:50   (   0.02,-137.20) (  -0.00,-137.31)   12.27                80
 04/26/2021   10:49:21   (  -0.02,-137.20) (   0.15,-137.90)   80.22                80
 04/27/2021   10:27:43   (  -0.02,-137.19) (  -0.88,-133.31)  441.90                80
 04/28/2021   22:52:00   (   0.02,-137.17) (  -0.26,-138.53)  153.85                80
 04/29/2021   22:33:02   (   0.02,-137.16) (   0.77,-133.94)  367.84                80
 05/01/2021   10:54:30   (  -0.02,-137.14) (   0.40,-139.12)  224.30                80
 05/02/2021   10:32:53   (  -0.02,-137.13) (  -0.63,-134.53)  297.02                80
 05/03/2021   22:54:28   (   0.01,-137.10) (  -0.58,-139.73)  299.87                80
 05/04/2021   22:38:11   (   0.01,-137.08) (   0.46,-135.14)  221.40                80