Simultaneous Nadir Overpasses (SNOs) between GOES-17 and NOAA-21
TLE Epoch: 2023 6 18.  Predictions up to the next  14.0 days:

     Date     Time(GOES-17)   GOES-17 Lat/Lon  NOAA-21 Lat/Lon    Distance(km)  Time Diff(sec)
 06/19/2023   08:37:55   (   0.01,-104.72) (   0.74,-108.08)  382.34                80
 06/20/2023   08:16:30   (   0.01,-104.72) (  -0.24,-103.54)  133.85                80
 06/21/2023   20:38:26   (  -0.01,-104.71) (  -0.93,-108.85)  471.87                80
 06/22/2023   20:22:20   (  -0.00,-104.71) (   0.06,-104.31)   44.86                80
 06/25/2023   08:25:23   (  -0.00,-104.73) (   0.06,-105.06)   37.50                80
 06/26/2023   08:03:58   (  -0.00,-104.73) (  -0.93,-100.52)  479.08                80
 06/27/2023   20:25:54   (   0.00,-104.72) (  -0.23,-105.83)  126.33                80
 06/28/2023   20:09:49   (   0.00,-104.72) (   0.76,-101.30)  390.48                80
 06/30/2023   08:31:36   (  -0.00,-104.74) (   0.40,-106.57)  208.26                80
 07/01/2023   08:10:10   (  -0.00,-104.73) (  -0.59,-102.03)  307.92                80