Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2021 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)
 04/13/2021   09:45:54   (  -0.01,-128.07) (  -0.51,-125.73)  265.24                80
 04/14/2021   22:07:51   (   0.00,-128.03) (  -0.65,-131.04)  342.77                80
 04/15/2021   21:51:45   (   0.01,-128.00) (   0.34,-126.50)  170.82                80
 04/17/2021   10:13:32   (   0.00,-127.95) (   0.87,-131.76)  433.87                80
 04/18/2021   09:52:07   (  -0.00,-127.92) (  -0.19,-127.23)   78.61                80
 04/20/2021   21:55:17   (  -0.00,-127.82) (  -0.04,-127.99)   18.98                80
 04/21/2021   21:39:11   (   0.00,-127.79) (   0.96,-123.45)  493.81                80
 04/23/2021   10:00:58   (   0.01,-127.74) (   0.25,-128.71)  111.46                80
 04/24/2021   09:39:33   (   0.00,-127.69) (  -0.81,-124.19)  400.37                80
 04/25/2021   22:01:29   (  -0.01,-127.62) (  -0.40,-129.48)  211.61                80
 04/26/2021   21:45:23   (  -0.00,-127.58) (   0.60,-124.94)  300.62                80