Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 1 7.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 01/07/2021   22:54:18   (   0.03,-137.23) (  -0.71,-140.38)  359.68                80
 01/08/2021   22:38:02   (   0.02,-137.23) (   0.35,-135.80)  163.26                80
 01/10/2021   10:56:50   (  -0.00,-137.23) (   0.85,-140.97)  427.56                80
 01/11/2021   10:37:52   (   0.01,-137.22) (  -0.15,-136.38)   95.01                80
 01/13/2021   22:43:13   (  -0.01,-137.21) (   0.05,-137.03)   21.78                80
 01/16/2021   10:45:45   (   0.01,-137.19) (   0.09,-137.62)   48.45                80
 01/17/2021   10:24:08   (   0.01,-137.19) (  -0.91,-133.03)  473.40                80
 01/18/2021   22:45:45   (  -0.01,-137.18) (  -0.25,-138.25)  122.56                80
 01/19/2021   22:29:27   (  -0.01,-137.17) (   0.75,-133.66)  399.08                80