Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 9 10.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 09/10/2021   10:49:58   (   0.04,-137.21) (   0.01,-137.06)   16.29                80
 09/12/2021   22:49:55   (  -0.04,-137.19) (  -0.17,-137.67)   55.62                80
 09/13/2021   22:33:38   (  -0.04,-137.18) (   0.90,-133.09)  466.78                80
 09/15/2021   10:52:25   (   0.03,-137.17) (   0.26,-138.27)  124.36                80
 09/16/2021   10:36:06   (   0.03,-137.16) (  -0.74,-133.67)  397.58                80
 09/17/2021   22:55:02   (  -0.01,-137.14) (  -0.42,-138.88)  198.69                80
 09/18/2021   22:38:44   (  -0.01,-137.12) (   0.64,-134.29)  323.25                80
 09/20/2021   10:57:32   (   0.01,-137.11) (   0.51,-139.47)  268.09                80
 09/21/2021   10:41:13   (   0.01,-137.10) (  -0.49,-134.87)  253.86                80
 09/22/2021   23:00:08   (  -0.01,-137.07) (  -0.67,-140.08)  342.54                80
 09/23/2021   22:43:50   (  -0.01,-137.06) (   0.34,-135.48)  179.12                80