Simultaneous Nadir Overpasses (SNOs) between GOES-15 and FY3D
TLE Epoch: 2021 6 8.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 06/09/2021   10:14:07   (   0.05,-128.52) (   0.10,-128.79)   30.49                80
 06/10/2021   09:52:30   (   0.05,-128.52) (  -0.94,-124.20)  492.24                80
 06/11/2021   22:14:06   (  -0.04,-128.43) (  -0.25,-129.41)  110.96                80
 06/12/2021   21:57:48   (  -0.05,-128.43) (   0.74,-124.81)  411.85                80
 06/14/2021   10:19:16   (   0.04,-128.50) (   0.35,-130.00)  170.62                80
 06/15/2021   09:57:38   (   0.05,-128.49) (  -0.64,-125.40)  351.65                80
 06/16/2021   22:19:14   (  -0.04,-128.39) (  -0.55,-130.61)  252.97                80
 06/17/2021   22:02:57   (  -0.05,-128.38) (   0.50,-126.02)  269.39                80
 06/19/2021   10:21:44   (   0.04,-128.45) (   0.65,-131.20)  313.24                80
 06/20/2021   10:02:45   (   0.05,-128.44) (  -0.34,-126.60)  208.46                80
 06/21/2021   22:24:22   (  -0.03,-128.33) (  -0.84,-131.81)  397.97                80