Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 1 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)
 01/13/2021   22:43:13   (   0.02,-137.22) (   0.04,-137.02)   22.81                80
 01/16/2021   10:45:45   (  -0.02,-137.22) (   0.09,-137.62)   46.10                80
 01/17/2021   10:24:08   (  -0.02,-137.22) (  -0.97,-133.04)  476.51                80
 01/18/2021   22:45:45   (   0.02,-137.22) (  -0.19,-138.26)  117.79                80
 01/19/2021   22:29:28   (   0.02,-137.22) (   0.81,-133.67)  404.60                80
 01/21/2021   10:50:56   (  -0.02,-137.21) (   0.37,-138.85)  187.45                80
 01/22/2021   10:29:20   (  -0.02,-137.20) (  -0.69,-134.27)  334.44                80
 01/23/2021   22:50:57   (   0.03,-137.20) (  -0.47,-139.49)  261.31                80
 01/24/2021   22:34:40   (   0.03,-137.18) (   0.53,-134.90)  260.08                80
 01/26/2021   10:56:08   (  -0.04,-137.16) (   0.64,-140.08)  333.43                80