Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-9
TLE Epoch: 2023 9 4.  Predictions up to the next  14.0 days:

     Date     Time(NOAA-21) NOAA-21 Lat/Lon Date Time(LANDSAT-9) LANDSAT-9 Lat/Lon    Distance(km)  Time Diff(sec)
 09/06/2023   07:34:11   ( -70.81,-118.68) 09/06/2023   07:35:18  ( -70.71,-116.50)   80.44                67
 09/06/2023   08:24:41   (  69.95,  49.99) 09/06/2023   08:24:57  (  69.96,  50.04)    2.10                16
 09/06/2023   09:15:22   ( -69.82,-142.50) 09/06/2023   09:14:27  ( -69.84,-142.49)    3.22                55
 09/08/2023   23:50:52   ( -70.01,  -1.66) 09/08/2023   23:52:02  ( -69.99,  -1.68)    2.46                70
 09/09/2023   00:41:36   (  69.89, 165.84) 09/09/2023   00:41:29  (  69.89, 165.82)    0.74                 7
 09/09/2023   01:32:14   ( -69.60, -26.41) 09/09/2023   01:31:01  ( -69.67, -26.85)   18.88                73
 09/11/2023   16:07:47   ( -69.96, 114.18) 09/11/2023   16:08:33  ( -69.96, 114.15)    1.42                46
 09/11/2023   16:58:31   (  69.84, -78.33) 09/11/2023   16:58:00  (  69.85, -78.36)    1.55                31
 09/14/2023   07:34:14   (  70.75,  61.40) 09/14/2023   07:35:22  (  70.65,  63.41)   74.63                68
 09/14/2023   08:24:42   ( -69.92,-129.99) 09/14/2023   08:25:03  ( -69.95,-129.98)    3.38                21
 09/14/2023   09:15:26   (  69.80,  37.50) 09/14/2023   09:14:31  (  69.78,  37.43)    3.47                55
 09/16/2023   23:50:55   (  70.03, 178.30) 09/16/2023   23:52:02  (  70.01, 178.36)    2.96                67
 09/17/2023   00:41:36   ( -69.89, -14.17) 09/17/2023   00:41:32  ( -69.91, -14.15)    3.28                 4
 09/17/2023   01:32:15   (  69.50, 153.70) 09/17/2023   01:31:03  (  69.58, 153.03)   27.20                72