Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2021 6 13.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 06/13/2021   21:45:58   (  -0.05,-128.43) (   0.69,-125.06)  383.23                80
 06/15/2021   10:07:48   (   0.04,-128.49) (   0.42,-130.35)  210.84                80
 06/16/2021   09:46:23   (   0.05,-128.48) (  -0.55,-125.81)  304.43                80
 06/17/2021   22:08:21   (  -0.04,-128.39) (  -0.66,-131.11)  310.73                80
 06/18/2021   21:52:17   (  -0.05,-128.38) (   0.38,-126.59)  204.58                80
 06/20/2021   10:11:26   (   0.04,-128.44) (   0.80,-131.87)  389.78                80
 06/21/2021   09:52:42   (   0.04,-128.43) (  -0.18,-127.33)  124.77                80
 06/22/2021   22:14:39   (  -0.03,-128.32) (  -1.02,-132.63)  492.43                80
 06/23/2021   21:58:36   (  -0.03,-128.30) (   0.02,-128.11)   21.86                80
 06/26/2021   09:59:02   (   0.03,-128.33) (   0.12,-128.86)   59.61                80