Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2018 4 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)
 04/10/2018   22:36:23   (  -0.09,-135.15) (  -0.58,-137.45)  261.93                80
 04/11/2018   22:14:59   (  -0.09,-135.17) (   0.43,-132.92)  257.61                80
 04/13/2018   10:36:47   (   0.09,-135.21) (   0.74,-138.19)  339.31                80
 04/14/2018   10:20:42   (   0.09,-135.23) (  -0.27,-133.66)  179.93                80
 04/15/2018   22:42:39   (  -0.09,-135.28) (  -0.94,-138.96)  419.74                80
 04/16/2018   22:21:15   (  -0.09,-135.30) (   0.12,-134.44)   99.00                80
 04/18/2018   10:43:04   (   0.09,-135.32) (   1.04,-139.71)  499.56                80
 04/19/2018   10:26:59   (   0.09,-135.34) (   0.04,-135.18)   18.77                80
 04/21/2018   22:27:31   (  -0.10,-135.38) (  -0.23,-135.95)   64.87                80
 04/22/2018   22:11:27   (  -0.10,-135.39) (   0.78,-131.42)  452.73                80