Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 9 19.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 09/20/2021   10:57:31   (   0.03,-137.20) (   0.52,-139.46)  257.63                80
 09/21/2021   10:41:13   (   0.03,-137.19) (  -0.49,-134.87)  265.41                80
 09/22/2021   23:00:08   (  -0.03,-137.18) (  -0.68,-140.07)  329.58                80
 09/23/2021   22:43:50   (  -0.03,-137.17) (   0.33,-135.48)  193.21                80
 09/25/2021   11:02:37   (   0.03,-137.17) (   0.81,-140.65)  396.91                80
 09/26/2021   10:46:18   (   0.03,-137.16) (  -0.20,-136.06)  125.35                80
 09/27/2021   23:05:14   (  -0.02,-137.13) (  -0.97,-141.26)  471.20                80
 09/28/2021   22:48:56   (  -0.02,-137.12) (   0.10,-136.68)   50.58                80
 10/01/2021   10:48:44   (   0.01,-137.08) (   0.08,-137.25)   20.12                80