Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2017 12 22.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 12/23/2017   10:21:14   (  -0.03,-135.38) (  -0.41,-133.79)  181.84                80
 12/24/2017   22:40:29   (   0.05,-135.28) (  -0.79,-139.09)  432.98                80
 12/25/2017   22:24:24   (   0.04,-135.27) (   0.20,-134.55)   81.90                80
 12/28/2017   10:24:46   (  -0.04,-135.29) (  -0.03,-135.28)    1.95                80
 12/30/2017   22:27:55   (   0.04,-135.16) (  -0.17,-136.05)  101.29                80
 12/31/2017   22:11:50   (   0.03,-135.13) (   0.83,-131.51)  412.42                80
 01/02/2018   10:30:57   (  -0.04,-135.15) (   0.34,-136.78)  185.58                80
 01/03/2018   10:14:52   (  -0.03,-135.12) (  -0.65,-132.24)  327.89                80
 01/04/2018   22:34:07   (   0.04,-135.01) (  -0.53,-137.54)  289.08                80