Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 6 12.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 06/12/2021   10:57:43   (   0.01,-137.20) (   0.56,-139.59)  272.87                80
 06/13/2021   10:36:06   (   0.00,-137.20) (  -0.49,-135.01)  249.87                80
 06/14/2021   23:00:22   (  -0.01,-137.19) (  -0.70,-140.22)  345.18                80
 06/15/2021   22:38:44   (  -0.00,-137.19) (   0.34,-135.63)  177.30                80
 06/17/2021   11:02:52   (   0.01,-137.18) (   0.80,-140.81)  412.98                80
 06/18/2021   10:41:13   (   0.01,-137.17) (  -0.18,-136.21)  109.23                80
 06/19/2021   23:05:31   (  -0.01,-137.15) (  -0.94,-141.43)  486.91                80
 06/20/2021   22:43:52   (  -0.00,-137.14) (   0.04,-136.83)   34.83                80
 06/23/2021   10:49:02   (  -0.01,-137.10) (   0.05,-137.42)   36.14                80
 06/24/2021   10:30:04   (  -0.01,-137.08) (  -0.99,-132.84)  484.79                80
 06/25/2021   22:49:01   (   0.01,-137.05) (  -0.19,-138.05)  113.19                80