Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-8
TLE Epoch: 2023 4 13.  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)
 04/13/2023   22:35:59   (  71.11,-164.39) 04/13/2023   22:37:04  (  71.01,-161.73)   96.90                65
 04/13/2023   23:26:23   ( -70.08,   4.58) 04/13/2023   23:26:49  ( -70.07,   4.52)    2.74                26
 04/14/2023   00:17:07   (  69.96, 172.07) 04/14/2023   00:16:16  (  69.97, 172.02)    1.98                51
 04/16/2023   14:52:35   (  70.35, -47.37) 04/16/2023   14:53:46  (  70.29, -46.94)   18.03                71
 04/16/2023   15:43:13   ( -70.06, 120.40) 04/16/2023   15:43:18  ( -70.07, 120.38)    1.20                 5
 04/16/2023   16:33:57   (  69.94, -72.12) 04/16/2023   16:32:45  (  69.96, -72.12)    1.78                72
 04/19/2023   07:09:21   (  70.13,  68.76) 04/19/2023   07:10:17  (  70.17,  68.76)    3.59                56
 04/19/2023   08:00:03   ( -70.05,-123.79) 04/19/2023   07:59:47  ( -70.06,-123.75)    2.07                16
 04/19/2023   08:50:34   (  69.24,  44.69) 04/19/2023   08:49:26  (  69.29,  42.84)   73.00                68
 04/21/2023   23:26:10   (  70.08,-175.38) 04/21/2023   23:26:47  (  70.10,-175.46)    3.57                37
 04/22/2023   00:16:52   ( -69.99,  -7.92) 04/22/2023   00:16:17  ( -70.00,  -7.97)    1.88                35
 04/24/2023   14:52:29   ( -70.93, 131.74) 04/24/2023   14:53:37  ( -70.80, 133.80)   76.44                68
 04/24/2023   15:42:59   (  70.10, -59.61) 04/24/2023   15:43:15  (  70.09, -59.60)    1.01                16
 04/24/2023   16:33:41   ( -70.00, 107.85) 04/24/2023   16:32:45  ( -69.99, 107.89)    2.35                56
 04/27/2023   07:09:05   ( -70.22,-111.32) 04/27/2023   07:10:17  ( -70.19,-111.23)    4.99                72
 04/27/2023   07:59:48   (  70.07,  56.22) 04/27/2023   07:59:44  (  70.07,  56.25)    1.09                 4
 04/27/2023   08:50:28   ( -69.87,-136.15) 04/27/2023   08:49:15  ( -69.92,-136.33)    9.02                73