Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2017 9 9.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 09/09/2017   22:27:58   (  -0.33,-135.10) (  -0.52,-135.88)   90.28                80
 09/10/2017   22:11:54   (  -0.33,-135.13) (   0.52,-131.36)  429.42                80
 09/12/2017   10:33:44   (   0.33,-135.20) (   0.64,-136.64)  163.79                80
 09/13/2017   10:12:19   (   0.33,-135.22) (  -0.34,-132.10)  354.56                80
 09/14/2017   22:34:16   (  -0.31,-135.21) (  -0.83,-137.41)  250.88                80
 09/15/2017   22:18:13   (  -0.32,-135.24) (   0.22,-132.89)  267.92                80
 09/17/2017   10:40:02   (   0.30,-135.31) (   0.94,-138.17)  325.12                80
 09/18/2017   10:18:38   (   0.31,-135.33) (  -0.05,-133.63)  192.88                80
 09/19/2017   22:40:35   (  -0.29,-135.31) (  -1.12,-138.94)  414.34                80
 09/20/2017   22:24:32   (  -0.30,-135.33) (  -0.07,-134.42)  104.33                80
 09/22/2017   10:46:21   (   0.28,-135.41) (   1.22,-139.70)  487.93                80
 09/23/2017   10:24:56   (   0.29,-135.42) (   0.23,-135.16)   29.78                80