Simultaneous Nadir Overpasses (SNOs) between GOES-15 and FY3D
TLE Epoch: 2021 9 18.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 09/18/2021   09:57:31   (   0.39,-127.98) (  -0.53,-123.97)  457.24                80
 09/19/2021   22:16:27   (  -0.37,-127.89) (  -0.64,-129.18)  146.27                80
 09/20/2021   22:00:08   (  -0.38,-127.86) (   0.37,-124.58)  374.07                80
 09/22/2021   10:18:56   (   0.36,-127.86) (   0.78,-129.76)  216.14                80
 09/23/2021   10:02:37   (   0.37,-127.83) (  -0.23,-125.16)  304.21                80
 09/24/2021   22:21:32   (  -0.35,-127.74) (  -0.94,-130.37)  299.56                80
 09/25/2021   22:05:14   (  -0.36,-127.71) (   0.07,-125.77)  220.24                80
 09/27/2021   10:24:01   (   0.33,-127.69) (   1.07,-130.95)  371.46                80
 09/28/2021   10:07:43   (   0.34,-127.66) (   0.06,-126.35)  148.09                80
 09/29/2021   22:26:38   (  -0.32,-127.56) (  -1.23,-131.56)  456.71                80
 09/30/2021   22:10:20   (  -0.32,-127.52) (  -0.22,-126.96)   62.33                80