Simultaneous Nadir Overpasses (SNOs) between GOES-15 and FY3D
TLE Epoch: 2021 9 1.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 09/01/2021   10:17:28   (   0.44,-128.28) (   0.72,-129.57)  146.72                80
 09/02/2021   10:01:10   (   0.44,-128.27) (  -0.28,-124.97)  375.83                80
 09/03/2021   22:20:05   (  -0.43,-128.21) (  -0.88,-130.18)  225.09                80
 09/04/2021   22:03:48   (  -0.43,-128.20) (   0.18,-125.60)  297.14                80
 09/06/2021   10:22:35   (   0.42,-128.24) (   0.99,-130.77)  288.74                80
 09/07/2021   10:06:18   (   0.42,-128.23) (  -0.07,-126.18)  233.48                80
 09/08/2021   22:25:12   (  -0.41,-128.15) (  -1.15,-131.38)  367.91                80
 09/09/2021   22:08:55   (  -0.42,-128.14) (  -0.09,-126.80)  153.95                80
 09/11/2021   10:27:42   (   0.40,-128.17) (   1.26,-131.97)  433.19                80
 09/12/2021   10:11:23   (   0.41,-128.15) (   0.25,-127.37)   88.28                80
 09/14/2021   22:11:20   (  -0.40,-128.04) (  -0.41,-127.98)    6.93                80