Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2018 12 19.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 12/19/2018   21:52:52   (   0.02,-128.56) (   0.43,-126.69)  213.14                80
 12/21/2018   10:12:01   (  -0.03,-128.67) (   0.70,-131.97)  376.06                80
 12/22/2018   09:55:55   (  -0.02,-128.66) (  -0.28,-127.43)  139.83                80
 12/23/2018   22:15:11   (   0.04,-128.54) (  -0.90,-132.74)  479.11                80
 12/24/2018   21:59:06   (   0.03,-128.53) (   0.07,-128.20)   36.67                80
 12/27/2018   09:59:30   (  -0.03,-128.62) (   0.02,-128.96)   38.15                80
 12/28/2018   09:43:24   (  -0.03,-128.60) (  -0.95,-124.42)  477.10                80
 12/29/2018   22:02:41   (   0.04,-128.47) (  -0.22,-129.72)  142.62                80
 12/30/2018   21:46:35   (   0.03,-128.46) (   0.76,-125.18)  372.74                80
 01/01/2019   10:05:43   (  -0.05,-128.56) (   0.38,-130.46)  217.46                80
 01/02/2019   09:49:38   (  -0.04,-128.54) (  -0.60,-125.93)  297.47                80