Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-8
TLE Epoch: 2023 4 19.  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)
 04/19/2023   07:09:21   (  70.16,  68.71) 04/19/2023   07:10:14  (  70.18,  68.79)    3.40                53
 04/19/2023   08:00:02   ( -70.03,-123.76) 04/19/2023   07:59:45  ( -70.01,-123.82)    3.05                17
 04/19/2023   08:50:32   (  69.16,  44.80) 04/19/2023   08:49:24  (  69.24,  42.79)   79.91                68
 04/21/2023   23:26:10   (  70.12,-175.43) 04/21/2023   23:26:42  (  70.10,-175.44)    2.34                32
 04/22/2023   00:16:51   ( -69.98,  -7.90) 04/22/2023   00:16:12  ( -69.98,  -7.97)    2.60                39
 04/24/2023   14:52:24   ( -70.67, 132.18) 04/24/2023   14:53:34  ( -70.57, 133.49)   49.45                70
 04/24/2023   15:42:59   (  70.09, -59.59) 04/24/2023   15:43:08  (  70.08, -59.58)    0.71                 9
 04/24/2023   16:33:40   ( -69.95, 107.94) 04/24/2023   16:32:38  ( -69.97, 107.90)    3.18                62
 04/27/2023   07:09:04   ( -70.18,-111.25) 04/27/2023   07:10:06  ( -70.19,-111.18)    3.31                62
 04/27/2023   07:59:47   (  70.02,  56.30) 04/27/2023   07:59:34  (  70.03,  56.23)    2.97                13
 04/27/2023   08:50:21   ( -69.50,-135.62) 04/27/2023   08:49:10  ( -69.59,-136.74)   44.47                71
 04/29/2023   23:25:51   ( -70.12,   4.63) 04/29/2023   23:26:31  ( -70.10,   4.58)    3.14                40
 04/30/2023   00:16:35   (  70.01, 172.10) 04/30/2023   00:15:57  (  70.04, 172.13)    2.69                38
 05/02/2023   14:52:08   (  70.75, -47.89) 05/02/2023   14:53:17  (  70.61, -46.41)   56.49                69
 05/02/2023   15:42:39   ( -70.07, 120.49) 05/02/2023   15:42:55  ( -70.07, 120.43)    2.45                16
 05/02/2023   16:33:23   (  69.97, -72.05) 05/02/2023   16:32:22  (  69.95, -72.09)    3.33                61