Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-9
TLE Epoch: 2023 12 19.  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)
 12/19/2023   07:34:48   (  69.98,  62.34) 12/19/2023   07:35:51  (  69.96,  62.35)    2.30                63
 12/19/2023   08:25:29   ( -69.84,-130.12) 12/19/2023   08:25:21  ( -69.84,-130.17)    2.06                 8
 12/19/2023   09:16:05   (  69.29,  37.97) 12/19/2023   09:14:55  (  69.35,  36.81)   46.18                70
 12/21/2023   23:51:42   (  69.90, 178.23) 12/21/2023   23:52:21  (  69.92, 178.18)    2.87                39
 12/22/2023   00:42:24   ( -69.81, -14.32) 12/22/2023   00:41:51  ( -69.81, -14.34)    0.76                33
 12/24/2023   15:18:05   ( -70.63, 125.55) 12/24/2023   15:19:14  ( -70.51, 127.27)   64.99                69
 12/24/2023   16:08:37   (  69.89, -65.98) 12/24/2023   16:08:50  (  69.92, -65.95)    3.04                13
 12/24/2023   16:59:19   ( -69.80, 101.48) 12/24/2023   16:58:20  ( -69.81, 101.54)    2.54                59
 12/27/2023   07:34:47   ( -70.00,-117.68) 12/27/2023   07:35:51  ( -69.99,-117.61)    3.07                64
 12/27/2023   08:25:30   (  69.84,  49.87) 12/27/2023   08:25:19  (  69.82,  49.81)    3.01                11
 12/27/2023   09:16:05   ( -69.37,-142.13) 12/27/2023   09:14:54  ( -69.44,-143.08)   37.92                71
 12/29/2023   23:51:40   ( -69.90,  -1.76) 12/29/2023   23:52:20  ( -69.92,  -1.81)    3.34                40
 12/30/2023   00:42:24   (  69.79, 165.72) 12/30/2023   00:41:47  (  69.81, 165.67)    2.60                37
 01/01/2024   15:18:02   (  70.49, -54.21) 01/01/2024   15:19:11  (  70.37, -52.92)   49.92                69
 01/01/2024   16:08:34   ( -69.86, 114.07) 01/01/2024   16:08:48  ( -69.88, 114.02)    3.03                14
 01/01/2024   16:59:18   (  69.76, -78.46) 01/01/2024   16:58:15  (  69.77, -78.50)    1.96                63