Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 9 9.  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) (  -0.00,-137.07)   16.21                80
 09/12/2021   22:49:55   (  -0.04,-137.19) (  -0.15,-137.68)   55.75                80
 09/13/2021   22:33:38   (  -0.04,-137.18) (   0.91,-133.09)  466.59                80
 09/15/2021   10:52:25   (   0.03,-137.17) (   0.25,-138.27)  124.72                80
 09/16/2021   10:36:07   (   0.03,-137.16) (  -0.76,-133.67)  397.21                80
 09/17/2021   22:55:02   (  -0.01,-137.13) (  -0.40,-138.88)  199.04                80
 09/18/2021   22:38:43   (  -0.01,-137.12) (   0.60,-134.28)  322.86                80
 09/20/2021   10:57:31   (   0.01,-137.11) (   0.55,-139.46)  268.60                80
 09/21/2021   10:41:13   (   0.01,-137.09) (  -0.52,-134.88)  253.33                80
 09/22/2021   23:00:08   (  -0.01,-137.07) (  -0.71,-140.07)  343.07                80