Simultaneous Nadir Overpasses (SNOs) between GOES-17 and FY3D
TLE Epoch: 2021 7 1.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 07/01/2021   22:35:11   (  -0.03,-137.18) (   0.56,-134.65)  289.01                80
 07/03/2021   10:59:17   (   0.03,-137.18) (   0.63,-139.82)  301.14                80
 07/04/2021   10:37:39   (   0.02,-137.17) (  -0.42,-135.23)  221.13                80
 07/05/2021   22:59:16   (  -0.02,-137.16) (  -0.76,-140.44)  374.70                80
 07/06/2021   22:42:58   (  -0.01,-137.15) (   0.29,-135.86)  147.10                80
 07/08/2021   11:04:26   (  -0.00,-137.13) (   0.85,-141.04)  444.63                80
 07/09/2021   10:42:47   (  -0.01,-137.11) (  -0.14,-136.44)   76.67                80
 07/11/2021   22:48:02   (   0.01,-137.07) (   0.02,-137.06)    0.63                76
 07/14/2021   10:50:35   (  -0.01,-137.02) (   0.14,-137.64)   71.41                80