Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2021 9 12.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 09/14/2021   09:59:43   (   0.41,-128.10) (   0.57,-128.87)   87.02                80
 09/15/2021   09:43:38   (   0.41,-128.07) (  -0.43,-124.33)  426.49                80
 09/16/2021   22:02:56   (  -0.39,-127.98) (  -0.74,-129.64)  188.87                80
 09/17/2021   21:46:51   (  -0.39,-127.95) (   0.26,-125.11)  324.49                80
 09/19/2021   10:06:00   (   0.38,-127.96) (   0.91,-130.38)  275.38                80
 09/20/2021   09:49:55   (   0.38,-127.93) (  -0.09,-125.84)  238.24                80
 09/21/2021   22:09:11   (  -0.37,-127.84) (  -1.13,-131.14)  376.68                80
 09/22/2021   21:53:07   (  -0.38,-127.81) (  -0.13,-126.61)  136.71                80
 09/24/2021   10:12:16   (   0.36,-127.81) (   1.24,-131.89)  464.00                80
 09/25/2021   09:56:12   (   0.37,-127.78) (   0.24,-127.36)   49.32                80