Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 12 6.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 12/06/2021   22:51:09   (   0.00,-137.18) (   0.11,-136.67)   57.99                80
 12/09/2021   10:52:28   (  -0.00,-137.17) (   0.09,-137.62)   51.59                80
 12/10/2021   10:36:46   (  -0.00,-137.16) (  -0.90,-133.17)  454.40                80
 12/11/2021   22:56:37   (   0.01,-137.15) (  -0.31,-138.61)  166.51                80
 12/12/2021   22:40:55   (   0.00,-137.14) (   0.68,-134.16)  339.43                80
 12/14/2021   11:00:36   (  -0.00,-137.12) (   0.52,-139.56)  276.59                80
 12/15/2021   10:44:53   (  -0.00,-137.11) (  -0.47,-135.11)  229.01                80
 12/16/2021   23:04:44   (  -0.00,-137.09) (  -0.78,-140.53)  392.82                80
 12/17/2021   22:49:01   (  -0.01,-137.07) (   0.21,-136.08)  112.29                80