Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 12 8.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 12/09/2021   10:52:28   (  -0.01,-137.21) (   0.10,-137.62)   47.20                80
 12/10/2021   10:36:45   (  -0.01,-137.21) (  -0.89,-133.17)  459.93                80
 12/11/2021   22:56:37   (   0.01,-137.21) (  -0.32,-138.61)  159.80                80
 12/12/2021   22:40:54   (   0.01,-137.21) (   0.68,-134.16)  347.23                80
 12/14/2021   11:00:36   (  -0.01,-137.21) (   0.52,-139.55)  266.64                80
 12/15/2021   10:44:53   (  -0.00,-137.21) (  -0.48,-135.11)  240.05                80
 12/16/2021   23:04:43   (  -0.00,-137.20) (  -0.78,-140.53)  380.54                80
 12/17/2021   22:49:01   (  -0.01,-137.19) (   0.22,-136.08)  125.70                80
 12/19/2021   11:08:42   (   0.01,-137.18) (   0.98,-141.48)  489.64                80
 12/20/2021   10:53:00   (   0.00,-137.17) (  -0.01,-137.03)   16.02                80