Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 4 10.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 04/10/2021   10:52:50   (  -0.03,-137.20) (   0.32,-138.85)  188.03                80
 04/11/2021   10:31:12   (  -0.03,-137.19) (  -0.71,-134.26)  333.92                80
 04/12/2021   22:52:48   (   0.03,-137.18) (  -0.51,-139.46)  260.89                80
 04/13/2021   22:36:31   (   0.03,-137.17) (   0.58,-134.89)  260.80                80
 04/15/2021   10:57:58   (  -0.03,-137.14) (   0.65,-140.05)  332.59                80
 04/16/2021   10:36:22   (  -0.03,-137.13) (  -0.43,-135.48)  188.52                80
 04/17/2021   22:57:57   (   0.03,-137.10) (  -0.77,-140.68)  407.83                80
 04/18/2021   22:41:40   (   0.03,-137.08) (   0.25,-136.09)  112.89                80
 04/20/2021   11:03:08   (  -0.02,-137.04) (   0.92,-141.27)  481.73                80
 04/21/2021   10:41:31   (  -0.02,-137.02) (  -0.11,-136.68)   38.56                80
 04/23/2021   22:44:08   (   0.01,-136.95) (  -0.06,-137.30)   39.06                80