Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 6 15.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 06/15/2021   22:38:44   (  -0.01,-137.20) (   0.33,-135.63)  178.86                80
 06/17/2021   11:02:51   (   0.02,-137.20) (   0.81,-140.80)  410.35                80
 06/18/2021   10:41:14   (   0.02,-137.20) (  -0.23,-136.22)  112.40                80
 06/19/2021   23:05:30   (  -0.02,-137.19) (  -0.96,-141.43)  483.04                80
 06/20/2021   22:43:53   (  -0.01,-137.18) (   0.09,-136.84)   39.21                80
 06/23/2021   10:49:02   (   0.00,-137.16) (   0.07,-137.42)   30.20                80
 06/24/2021   10:27:24   (  -0.01,-137.14) (  -0.97,-132.83)  491.19                80
 06/25/2021   22:49:01   (   0.01,-137.11) (  -0.21,-138.04)  106.18                80
 06/26/2021   22:32:43   (   0.01,-137.09) (   0.83,-133.45)  415.08                80
 06/28/2021   10:51:30   (  -0.01,-137.07) (   0.31,-138.63)  176.93                80