Simultaneous Nadir Overpasses (SNOs) between GOES-15 and FY3D
TLE Epoch: 2021 5 30.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 05/30/2021   10:01:11   (   0.06,-128.46) (  -0.43,-126.37)  238.12                80
 05/31/2021   22:22:47   (  -0.06,-128.40) (  -0.75,-131.58)  362.18                80
 06/01/2021   22:06:29   (  -0.07,-128.41) (   0.23,-126.98)  162.37                80
 06/03/2021   10:27:57   (   0.06,-128.50) (   0.87,-132.17)  417.48                80
 06/04/2021   10:06:19   (   0.07,-128.51) (  -0.17,-127.58)  106.51                80
 06/05/2021   22:27:56   (  -0.06,-128.44) (  -1.01,-132.79)  495.01                80
 06/06/2021   22:11:37   (  -0.06,-128.45) (  -0.03,-128.19)   29.23                80
 06/09/2021   10:14:08   (   0.06,-128.55) (   0.09,-128.80)   27.72                80
 06/10/2021   09:52:30   (   0.06,-128.55) (  -0.90,-124.20)  495.49                80
 06/11/2021   22:14:06   (  -0.05,-128.46) (  -0.29,-129.41)  107.85                80
 06/12/2021   21:57:48   (  -0.06,-128.46) (   0.76,-124.82)  415.34                80