Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-8
TLE Epoch: 2023 12 18.  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   (  69.96, -59.74) 12/20/2023   15:43:58  (  69.97, -59.71)    1.47                43
 12/20/2023   16:33:57   ( -69.87, 107.72) 12/20/2023   16:33:28  ( -69.86, 107.77)    2.45                29
 12/23/2023   07:09:41   ( -70.84,-112.67) 12/23/2023   07:10:48  ( -70.74,-110.35)   85.79                67
 12/23/2023   08:00:10   (  69.94,  56.06) 12/23/2023   08:00:28  (  69.92,  56.10)    3.16                18
 12/23/2023   08:50:51   ( -69.79,-136.41) 12/23/2023   08:49:58  ( -69.81,-136.41)    1.87                53
 12/25/2023   23:26:20   ( -69.99,   4.45) 12/25/2023   23:27:30  ( -70.00,   4.46)    1.70                70
 12/26/2023   00:17:04   (  69.88, 171.92) 12/26/2023   00:16:57  (  69.89, 171.95)    1.60                 7
 12/26/2023   01:07:42   ( -69.57, -20.31) 12/26/2023   01:06:30  ( -69.62, -20.79)   19.37                72
 12/28/2023   15:43:14   ( -69.94, 120.30) 12/28/2023   15:43:59  ( -69.95, 120.27)    1.93                45
 12/28/2023   16:33:57   (  69.83, -72.23) 12/28/2023   16:33:25  (  69.84, -72.25)    0.99                32
 12/31/2023   07:09:38   (  70.68,  67.60) 12/31/2023   07:10:46  (  70.57,  69.42)   68.42                68
 12/31/2023   08:00:07   ( -69.90,-123.86) 12/31/2023   08:00:26  ( -69.92,-123.88)    3.30                19
 12/31/2023   08:50:51   (  69.79,  43.61) 12/31/2023   08:49:53  (  69.80,  43.60)    1.89                58