Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2018 4 13.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 04/14/2018   10:20:43   (   0.09,-135.24) (  -0.28,-133.66)  180.32                80
 04/15/2018   22:42:39   (  -0.09,-135.29) (  -0.94,-138.96)  419.17                80
 04/16/2018   22:21:15   (  -0.09,-135.31) (   0.13,-134.44)   99.69                80
 04/18/2018   10:43:03   (   0.09,-135.33) (   1.10,-139.70)  498.74                80
 04/19/2018   10:26:59   (   0.09,-135.35) (   0.03,-135.18)   19.75                80
 04/21/2018   22:27:31   (  -0.09,-135.39) (  -0.23,-135.95)   63.63                80
 04/22/2018   22:11:27   (  -0.10,-135.40) (   0.78,-131.42)  454.08                80
 04/24/2018   10:30:35   (   0.10,-135.41) (   0.39,-136.69)  145.96                80
 04/25/2018   10:14:30   (   0.10,-135.42) (  -0.62,-132.16)  371.64                80
 04/26/2018   22:33:48   (  -0.10,-135.45) (  -0.52,-137.47)  230.17                80