Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 9 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)
 09/10/2021   10:49:59   (   0.04,-137.20) (  -0.01,-137.07)   16.00                80
 09/12/2021   22:49:55   (  -0.04,-137.19) (  -0.15,-137.68)   56.00                80
 09/13/2021   22:33:37   (  -0.04,-137.18) (   0.86,-133.08)  466.29                80
 09/15/2021   10:52:24   (   0.03,-137.17) (   0.30,-138.26)  125.21                80
 09/16/2021   10:36:07   (   0.03,-137.15) (  -0.76,-133.68)  396.66                80
 09/17/2021   22:55:02   (  -0.01,-137.13) (  -0.40,-138.88)  199.52                80
 09/18/2021   22:38:44   (  -0.01,-137.12) (   0.61,-134.29)  322.34                80
 09/20/2021   10:57:31   (   0.01,-137.10) (   0.54,-139.46)  269.31                80
 09/21/2021   10:41:12   (   0.01,-137.09) (  -0.47,-134.87)  252.57                80