Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-8
TLE Epoch: 2023 12 20.  Predictions up to the next  14.0 days:

     Date     Time(NOAA-21) NOAA-21 Lat/Lon Date Time(LANDSAT-8) LANDSAT-8 Lat/Lon    Distance(km)  Time Diff(sec)
 12/20/2023   15:43:15   (  69.94, -59.72) 12/20/2023   15:43:59  (  69.92, -59.77)    2.81                44
 12/20/2023   16:33:57   ( -69.86, 107.73) 12/20/2023   16:33:28  ( -69.87, 107.79)    2.72                29
 12/23/2023   07:09:41   ( -70.83,-112.65) 12/23/2023   07:10:48  ( -70.75,-110.33)   85.69                67
 12/23/2023   08:00:10   (  69.93,  56.08) 12/23/2023   08:00:28  (  69.93,  56.13)    1.97                18
 12/23/2023   08:50:51   ( -69.78,-136.39) 12/23/2023   08:49:59  ( -69.77,-136.47)    3.26                52
 12/25/2023   23:26:20   ( -69.98,   4.46) 12/25/2023   23:27:31  ( -69.97,   4.41)    2.20                71
 12/26/2023   00:17:04   (  69.87, 171.94) 12/26/2023   00:16:58  (  69.86, 171.90)    1.79                 6
 12/26/2023   01:07:42   ( -69.62, -20.37) 12/26/2023   01:06:29  ( -69.64, -20.76)   15.25                73
 12/28/2023   15:43:13   ( -69.93, 120.31) 12/28/2023   15:43:59  ( -69.93, 120.23)    3.02                46
 12/28/2023   16:33:57   (  69.82, -72.21) 12/28/2023   16:33:26  (  69.81, -72.28)    2.79                31
 12/31/2023   07:09:38   (  70.67,  67.61) 12/31/2023   07:10:46  (  70.61,  69.48)   69.30                68
 12/31/2023   08:00:07   ( -69.89,-123.85) 12/31/2023   08:00:27  ( -69.91,-123.91)    2.71                20
 12/31/2023   08:50:51   (  69.78,  43.62) 12/31/2023   08:49:54  (  69.79,  43.57)    1.90                57
 01/02/2024   23:26:20   (  70.01,-175.58) 01/02/2024   23:27:24  (  70.01,-175.51)    2.76                64
 01/03/2024   00:17:01   ( -69.86,  -8.03) 01/03/2024   00:16:55  ( -69.86,  -8.09)    2.06                 6
 01/03/2024   01:07:38   (  69.38, 159.98) 01/03/2024   01:06:27  (  69.46, 159.02)   38.58                71