Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2019 9 21.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 09/21/2019   22:33:12   (   0.00,-137.21) (   0.19,-136.41)   91.09                80
 09/24/2019   10:35:48   (  -0.02,-137.19) (  -0.03,-137.04)   17.31                80
 09/26/2019   22:38:34   (   0.01,-137.17) (  -0.10,-137.71)   61.35                80
 09/27/2019   22:22:19   (   0.01,-137.16) (   0.90,-133.14)  458.84                80
 09/29/2019   10:41:10   (  -0.00,-137.15) (   0.26,-138.34)  136.01                80
 09/30/2019   10:24:55   (   0.00,-137.13) (  -0.74,-133.76)  383.85                80
 10/01/2019   22:43:55   (  -0.01,-137.11) (  -0.45,-139.00)  215.93                80
 10/02/2019   22:27:39   (  -0.01,-137.10) (   0.56,-134.42)  303.70                80
 10/04/2019   10:46:31   (   0.02,-137.07) (   0.60,-139.63)  292.15                80