Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 12 11.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 12/11/2021   22:56:38   (   0.02,-137.21) (  -0.27,-138.62)  160.05                80
 12/12/2021   22:40:55   (   0.01,-137.21) (   0.73,-134.17)  347.00                80
 12/14/2021   11:00:35   (  -0.02,-137.21) (   0.53,-139.55)  267.39                80
 12/15/2021   10:44:53   (  -0.01,-137.21) (  -0.47,-135.10)  239.27                80
 12/16/2021   23:04:44   (   0.01,-137.19) (  -0.73,-140.54)  381.05                80
 12/17/2021   22:49:02   (   0.00,-137.19) (   0.27,-136.09)  125.20                80
 12/19/2021   11:08:42   (  -0.00,-137.18) (   0.99,-141.47)  490.48                80
 12/20/2021   10:53:00   (   0.00,-137.16) (  -0.01,-137.03)   15.31                80
 12/22/2021   22:54:27   (  -0.01,-137.12) (  -0.23,-138.01)  101.20                80
 12/23/2021   22:38:45   (  -0.01,-137.11) (   0.77,-133.56)  404.03                80