Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2021 6 11.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 06/11/2021   09:40:04   (   0.05,-128.51) (  -0.89,-124.29)  481.16                80
 06/12/2021   22:02:02   (  -0.04,-128.43) (  -0.29,-129.59)  132.51                80
 06/13/2021   21:45:57   (  -0.05,-128.43) (   0.69,-125.06)  383.33                80
 06/15/2021   10:07:46   (   0.04,-128.49) (   0.46,-130.34)  210.59                80
 06/16/2021   09:46:22   (   0.05,-128.48) (  -0.53,-125.80)  304.72                80
 06/17/2021   22:08:19   (  -0.04,-128.39) (  -0.65,-131.11)  310.35                80
 06/18/2021   21:52:15   (  -0.05,-128.38) (   0.34,-126.58)  205.01                80
 06/20/2021   10:11:24   (   0.04,-128.44) (   0.81,-131.85)  389.23                80
 06/21/2021   09:52:40   (   0.05,-128.42) (  -0.18,-127.32)  125.37                80
 06/22/2021   22:14:37   (  -0.03,-128.31) (  -0.99,-132.63)  491.72                80
 06/23/2021   21:58:32   (  -0.03,-128.29) (  -0.00,-128.09)   22.66                80