Simultaneous Nadir Overpasses (SNOs) between GOES-17 and NPP
TLE Epoch: 2021 9 13.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 09/13/2021   10:19:06   (   0.05,-137.19) (  -0.71,-133.91)  374.99                80
 09/14/2021   22:41:02   (  -0.04,-137.17) (  -0.52,-139.20)  231.94                80
 09/15/2021   22:24:59   (  -0.04,-137.16) (   0.54,-134.68)  283.25                80
 09/17/2021   10:44:07   (   0.03,-137.15) (   0.63,-139.95)  318.59                80
 09/18/2021   10:28:03   (   0.02,-137.14) (  -0.37,-135.42)  196.44                80
 09/19/2021   22:47:20   (  -0.01,-137.12) (  -0.80,-140.73)  410.96                80
 09/20/2021   22:31:16   (  -0.01,-137.11) (   0.21,-136.20)  104.19                80
 09/22/2021   10:50:24   (   0.01,-137.09) (   0.97,-141.47)  497.67                80
 09/23/2021   10:34:19   (   0.02,-137.08) (  -0.04,-136.93)   17.33                80
 09/25/2021   22:34:51   (  -0.02,-137.03) (  -0.18,-137.70)   76.44                80
 09/26/2021   22:18:47   (  -0.02,-137.01) (   0.83,-133.16)  437.76                80