Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2021 9 4.  Predictions up to the next  14.0 days:

     Date     Time(GOES-15)   GOES-15 Lat/Lon  NPP Lat/Lon    Distance(km)  Time Diff(sec)
 09/05/2021   22:09:06   (  -0.42,-128.19) (  -1.10,-131.14)  336.32                80
 09/06/2021   21:53:01   (  -0.43,-128.18) (  -0.10,-126.61)  179.02                80
 09/08/2021   10:12:11   (   0.42,-128.22) (   1.22,-131.89)  417.57                80
 09/09/2021   09:56:06   (   0.42,-128.21) (   0.22,-127.36)   97.65                80
 09/11/2021   21:59:19   (  -0.42,-128.12) (  -0.40,-128.13)    2.54                80
 09/14/2021   09:59:43   (   0.41,-128.13) (   0.57,-128.87)   84.50                80
 09/15/2021   09:43:38   (   0.41,-128.10) (  -0.43,-124.33)  429.58                80
 09/16/2021   22:02:56   (  -0.39,-128.02) (  -0.74,-129.64)  184.59                80
 09/17/2021   21:46:51   (  -0.39,-128.00) (   0.26,-125.11)  329.34                80