Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 6 13.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 06/13/2021   10:36:06   (   0.01,-137.20) (  -0.51,-135.01)  249.89                80
 06/14/2021   23:00:22   (  -0.01,-137.19) (  -0.68,-140.22)  345.20                80
 06/15/2021   22:38:45   (  -0.01,-137.18) (   0.36,-135.63)  177.21                80
 06/17/2021   11:02:51   (   0.01,-137.18) (   0.84,-140.80)  413.18                80
 06/18/2021   10:41:14   (   0.01,-137.17) (  -0.20,-136.21)  108.90                80
 06/19/2021   23:05:30   (  -0.01,-137.15) (  -0.99,-141.42)  487.26                80
 06/20/2021   22:43:52   (  -0.01,-137.14) (   0.05,-136.83)   34.30                80
 06/23/2021   10:49:02   (  -0.00,-137.10) (   0.05,-137.42)   36.91                80
 06/24/2021   10:27:24   (  -0.01,-137.08) (  -0.94,-132.83)  483.95                80
 06/25/2021   22:49:00   (   0.01,-137.04) (  -0.25,-138.03)  114.21                80
 06/26/2021   22:32:43   (   0.01,-137.02) (   0.80,-133.45)  406.46                80