Simultaneous Nadir Overpasses (SNOs) between GOES-15 and NPP
TLE Epoch: 2021 1 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)
 01/14/2021   21:55:33   (  -0.26,-128.08) (  -0.23,-128.02)    7.58                80
 01/17/2021   10:01:16   (   0.28,-127.98) (   0.42,-128.75)   87.30                80
 01/18/2021   09:39:51   (   0.25,-127.96) (  -0.60,-124.22)  426.38                80
 01/19/2021   22:04:27   (  -0.30,-127.98) (  -0.66,-129.51)  175.24                80
 01/20/2021   21:43:02   (  -0.27,-127.96) (   0.36,-124.98)  338.16                80
 01/22/2021   10:07:29   (   0.32,-127.87) (   0.85,-130.25)  271.06                80
 01/23/2021   09:46:05   (   0.30,-127.84) (  -0.17,-125.72)  242.04                80
 01/24/2021   22:10:41   (  -0.34,-127.85) (  -1.02,-131.02)  360.54                80
 01/25/2021   21:49:17   (  -0.32,-127.82) (  -0.00,-126.49)  152.14                80