Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2021 6 18.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 06/18/2021   21:52:17   (  -0.04,-128.39) (   0.34,-126.58)  205.51                80
 06/20/2021   10:11:38   (   0.03,-128.46) (   0.77,-131.87)  388.52                69
 06/21/2021   09:52:43   (   0.03,-128.44) (  -0.20,-127.33)  126.28                80
 06/22/2021   22:14:40   (  -0.02,-128.34) (  -1.00,-132.64)  490.44                80
 06/23/2021   21:58:36   (  -0.02,-128.32) (   0.04,-128.11)   24.18                80
 06/26/2021   09:59:02   (   0.02,-128.36) (   0.10,-128.86)   56.64                80
 06/27/2021   09:42:58   (   0.03,-128.34) (  -0.87,-124.33)  457.59                80
 06/28/2021   22:02:15   (  -0.01,-128.23) (  -0.32,-129.63)  159.95                80
 06/29/2021   21:46:11   (  -0.02,-128.21) (   0.66,-125.10)  354.54                80
 07/01/2021   10:05:21   (   0.01,-128.27) (   0.45,-130.38)  240.23                80
 07/02/2021   09:49:16   (   0.02,-128.25) (  -0.52,-125.85)  273.91                80