Simultaneous Nadir Overpasses (SNOs) between GOES-15 and FY3D
TLE Epoch: 2021 6 19.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 06/20/2021   10:02:46   (   0.03,-128.46) (  -0.40,-126.61)  210.45                80
 06/21/2021   22:24:23   (  -0.02,-128.35) (  -0.79,-131.82)  395.24                80
 06/22/2021   22:08:05   (  -0.02,-128.34) (   0.25,-127.23)  126.60                80
 06/24/2021   10:26:52   (   0.00,-128.40) (   0.88,-132.41)  456.62                80
 06/25/2021   10:10:34   (   0.01,-128.38) (  -0.10,-127.81)   64.62                80
 06/27/2021   22:10:33   (  -0.01,-128.25) (  -0.04,-128.44)   21.12                80
 06/30/2021   10:13:02   (   0.01,-128.29) (   0.19,-129.02)   82.81                80
 07/01/2021   09:56:44   (   0.02,-128.27) (  -0.86,-124.43)  438.45                80
 07/02/2021   22:15:40   (   0.00,-128.15) (  -0.32,-129.64)  169.08                80