Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2021 4 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)
 04/18/2021   09:52:06   (   0.00,-127.92) (  -0.13,-127.22)   78.89                80
 04/20/2021   21:55:17   (  -0.01,-127.82) (  -0.03,-127.99)   18.82                80
 04/21/2021   21:39:12   (  -0.01,-127.79) (   0.96,-123.45)  494.07                80
 04/23/2021   10:00:58   (   0.02,-127.74) (   0.24,-128.71)  111.03                80
 04/24/2021   09:39:32   (   0.01,-127.70) (  -0.75,-124.17)  400.81                80
 04/25/2021   22:01:28   (  -0.02,-127.62) (  -0.46,-129.47)  211.28                80
 04/26/2021   21:45:23   (  -0.01,-127.58) (   0.59,-124.94)  300.96                80
 04/28/2021   10:07:10   (   0.02,-127.53) (   0.61,-130.20)  304.07                80
 04/29/2021   09:45:44   (   0.01,-127.48) (  -0.39,-125.66)  206.92                80
 04/30/2021   22:07:39   (  -0.02,-127.38) (  -0.82,-130.96)  407.73                80
 05/01/2021   21:51:34   (  -0.01,-127.33) (   0.18,-126.42)  103.71                80