Simultaneous Nadir Overpasses (SNOs) between GOES-17 and NPP
TLE Epoch: 2021 9 18.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 09/18/2021   10:28:02   (   0.04,-137.20) (  -0.34,-135.41)  203.30                80
 09/19/2021   22:47:19   (  -0.03,-137.19) (  -0.83,-140.72)  402.75                80
 09/20/2021   22:31:15   (  -0.03,-137.19) (   0.17,-136.19)  113.32                80
 09/22/2021   10:50:23   (   0.03,-137.19) (   1.00,-141.46)  487.07                80
 09/23/2021   10:34:19   (   0.03,-137.18) (  -0.00,-136.92)   28.83                80
 09/25/2021   22:34:52   (  -0.03,-137.15) (  -0.15,-137.70)   62.69                80
 09/26/2021   22:18:47   (  -0.03,-137.14) (   0.85,-133.17)  452.43                80
 09/28/2021   10:37:56   (   0.02,-137.13) (   0.32,-138.44)  149.66                80
 09/29/2021   10:21:51   (   0.02,-137.11) (  -0.68,-133.90)  364.88                80
 09/30/2021   22:41:08   (  -0.01,-137.07) (  -0.47,-139.21)  243.71                80
 10/01/2021   22:25:04   (  -0.01,-137.05) (   0.53,-134.68)  270.49                80