Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-9
TLE Epoch: 2023 1 1.  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)
 01/01/2023   06:45:16   ( -70.28,-105.14) 01/01/2023   06:46:28  ( -70.22,-104.91)   10.76                72
 01/01/2023   07:35:58   (  70.06,  62.52) 01/01/2023   07:35:56  (  70.06,  62.51)    0.85                 2
 01/01/2023   08:26:39   ( -69.92,-129.96) 01/01/2023   08:25:26  ( -69.95,-130.01)    4.48                73
 01/03/2023   23:02:08   ( -70.12,  10.88) 01/03/2023   23:02:59  ( -70.14,  10.85)    2.33                51
 01/03/2023   23:52:52   (  70.00, 178.36) 01/03/2023   23:52:26  (  70.03, 178.34)    3.21                26
 01/04/2023   00:43:18   ( -69.07, -12.97) 01/04/2023   00:42:11  ( -69.10, -15.29)   92.17                67
 01/06/2023   14:28:37   (  71.11, -42.27) 01/06/2023   14:29:43  (  71.01, -39.60)   97.09                66
 01/06/2023   15:19:01   ( -70.07, 126.71) 01/06/2023   15:19:28  ( -70.09, 126.65)    2.96                27
 01/06/2023   16:09:45   (  69.96, -65.81) 01/06/2023   16:08:55  (  69.98, -65.86)    2.96                50
 01/09/2023   06:45:15   (  70.23,  74.92) 01/09/2023   06:46:26  (  70.23,  75.10)    6.82                71
 01/09/2023   07:35:56   ( -70.08,-117.54) 01/09/2023   07:35:57  ( -70.07,-117.49)    2.25                 1
 01/09/2023   08:26:38   (  69.87,  50.10) 01/09/2023   08:25:25  (  69.90,  49.91)    7.95                73
 01/11/2023   23:02:08   (  70.15,-169.19) 01/11/2023   23:02:56  (  70.13,-169.16)    2.18                48
 01/11/2023   23:52:50   ( -70.05,  -1.72) 01/11/2023   23:52:26  ( -70.03,  -1.67)    2.95                24
 01/14/2023   15:19:01   (  70.07, -53.30) 01/14/2023   15:19:25  (  70.06, -53.37)    2.57                24
 01/14/2023   16:09:43   ( -69.97, 114.16) 01/14/2023   16:08:55  ( -69.97, 114.13)    1.52                48