Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-9
TLE Epoch: 2023 9 14.  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)
 09/14/2023   07:34:15   (  70.79,  61.32) 09/14/2023   07:35:22  (  70.70,  63.48)   79.60                67
 09/14/2023   08:24:42   ( -69.92,-129.99) 09/14/2023   08:25:04  ( -69.93,-130.01)    1.07                22
 09/14/2023   09:15:27   (  69.85,  37.43) 09/14/2023   09:14:31  (  69.83,  37.49)    2.88                56
 09/16/2023   23:50:55   (  70.02, 178.31) 09/16/2023   23:52:03  (  70.01, 178.34)    1.90                68
 09/17/2023   00:41:36   ( -69.89, -14.18) 09/17/2023   00:41:33  ( -69.90, -14.18)    0.99                 3
 09/17/2023   01:32:16   (  69.55, 153.63) 09/17/2023   01:31:04  (  69.57, 153.02)   24.07                72
 09/19/2023   16:07:49   (  69.95, -65.81) 09/19/2023   16:08:33  (  69.94, -65.87)    2.54                44
 09/19/2023   16:58:31   ( -69.86, 101.63) 09/19/2023   16:58:02  ( -69.88, 101.69)    3.12                29
 09/22/2023   07:34:15   ( -70.84,-118.77) 09/22/2023   07:35:22  ( -70.71,-116.51)   84.08                67
 09/22/2023   08:24:44   (  69.93,  49.97) 09/22/2023   08:25:01  (  69.94,  50.02)    1.84                17
 09/22/2023   09:15:25   ( -69.80,-142.50) 09/22/2023   09:14:32  ( -69.78,-142.57)    3.19                53
 09/24/2023   23:50:54   ( -70.00,  -1.66) 09/24/2023   23:52:02  ( -70.02,  -1.62)    3.22                68
 09/25/2023   00:41:38   (  69.88, 165.82) 09/25/2023   00:41:29  (  69.91, 165.86)    3.31                 9
 09/25/2023   01:32:15   ( -69.53, -26.34) 09/25/2023   01:31:03  ( -69.59, -26.95)   24.38                72
 09/27/2023   16:07:47   ( -69.95, 114.18) 09/27/2023   16:08:29  ( -69.96, 114.18)    0.87                42
 09/27/2023   16:58:31   (  69.84, -78.34) 09/27/2023   16:57:56  (  69.84, -78.34)    0.34                35