Simultaneous Nadir Overpasses (SNOs) between GOES-18 and NOAA-21
TLE Epoch: 2023 6 16.  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)
 06/16/2023   22:16:48   (   0.02,-137.00) (   0.90,-133.05)  450.85                80
 06/18/2023   10:35:55   (  -0.02,-137.00) (   0.27,-138.32)  149.76                80
 06/19/2023   10:19:50   (  -0.02,-136.99) (  -0.71,-133.78)  366.03                80
 06/20/2023   22:39:06   (   0.01,-136.98) (  -0.46,-139.09)  240.49                80
 06/21/2023   22:23:00   (   0.00,-136.97) (   0.53,-134.55)  275.19                80
 06/23/2023   10:42:08   (   0.00,-136.96) (   0.64,-139.82)  326.04                80
 06/24/2023   10:26:02   (   0.01,-136.95) (  -0.35,-135.28)  189.43                80
 06/25/2023   22:45:19   (  -0.01,-136.92) (  -0.81,-140.59)  417.80                80
 06/26/2023   22:29:13   (  -0.01,-136.91) (   0.18,-136.06)   97.30                80
 06/29/2023   10:32:15   (   0.01,-136.87) (  -0.00,-136.79)    9.39                80