Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2018 12 14.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 12/14/2018   21:46:38   (  -0.00,-128.56) (   0.76,-125.18)  385.24                80
 12/16/2018   10:05:46   (  -0.02,-128.67) (   0.37,-130.46)  203.33                80
 12/17/2018   09:49:41   (  -0.01,-128.67) (  -0.61,-125.92)  313.26                80
 12/18/2018   22:08:57   (   0.03,-128.56) (  -0.58,-131.23)  304.41                80
 12/19/2018   21:52:53   (   0.01,-128.55) (   0.46,-126.70)  212.07                80
 12/21/2018   10:12:00   (  -0.03,-128.66) (   0.73,-131.97)  377.21                80
 12/22/2018   09:55:56   (  -0.02,-128.65) (  -0.30,-127.44)  138.47                80
 12/23/2018   22:15:11   (   0.03,-128.52) (  -0.93,-132.74)  481.10                80
 12/24/2018   21:59:06   (   0.02,-128.51) (   0.11,-128.21)   34.35                80
 12/27/2018   09:59:29   (  -0.03,-128.59) (   0.05,-128.95)   40.75                80