Simultaneous Nadir Overpasses (SNOs) between GOES-18 and NOAA-21
TLE Epoch: 2023 6 20.  Predictions up to the next  14.0 days:

     Date     Time(GOES-18)   GOES-18 Lat/Lon  NOAA-21 Lat/Lon    Distance(km)  Time Diff(sec)
 06/20/2023   22:39:06   (   0.01,-137.00) (  -0.45,-139.09)  237.74                80
 06/21/2023   22:23:01   (   0.01,-137.00) (   0.54,-134.55)  279.13                80
 06/23/2023   10:42:08   (  -0.00,-137.02) (   0.63,-139.82)  319.82                80
 06/24/2023   10:26:02   (   0.00,-137.02) (  -0.36,-135.28)  196.87                80
 06/25/2023   22:45:19   (  -0.00,-137.00) (  -0.80,-140.59)  408.93                80
 06/26/2023   22:29:13   (  -0.01,-137.00) (   0.19,-136.06)  107.39                80
 06/28/2023   10:48:20   (   0.00,-137.01) (   0.97,-141.33)  492.80                80
 06/29/2023   10:32:15   (   0.00,-137.00) (  -0.02,-136.79)   23.00                80
 07/01/2023   22:32:46   (   0.01,-136.96) (  -0.13,-137.57)   69.65                80
 07/02/2023   22:16:40   (   0.00,-136.94) (   0.86,-133.03)  445.17                80
 07/04/2023   10:35:48   (  -0.01,-136.92) (   0.29,-138.31)  157.23                80