Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and LANDSAT-9
TLE Epoch: 2023 4 13.  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)
 04/15/2023   07:34:49   ( -70.09,-117.54) 04/15/2023   07:35:20  ( -70.09,-117.51)    1.67                31
 04/15/2023   08:25:33   (  69.98,  49.94) 04/15/2023   08:24:47  (  69.98,  49.99)    2.12                46
 04/17/2023   23:01:02   (  70.43,-169.59) 04/17/2023   23:02:13  (  70.36,-168.87)   28.31                71
 04/17/2023   23:51:38   ( -70.02,  -1.65) 04/17/2023   23:51:47  ( -70.02,  -1.71)    2.22                 9
 04/18/2023   00:42:22   (  69.91, 165.83) 04/18/2023   00:41:14  (  69.92, 165.78)    1.67                68
 04/20/2023   15:17:45   (  70.11, -53.31) 04/20/2023   15:18:42  (  70.09, -53.35)    2.30                57
 04/20/2023   16:08:27   ( -70.02, 114.15) 04/20/2023   16:08:11  ( -70.04, 114.20)    2.99                16
 04/20/2023   16:58:58   (  69.22, -77.38) 04/20/2023   16:57:50  (  69.26, -79.21)   72.25                68
 04/23/2023   07:34:34   (  70.06,  62.55) 04/23/2023   07:35:07  (  70.07,  62.51)    2.08                33
 04/23/2023   08:25:16   ( -69.97,-129.99) 04/23/2023   08:24:37  ( -69.97,-130.01)    0.81                39
 04/25/2023   23:00:48   ( -70.60,  10.18) 04/25/2023   23:01:58  ( -70.52,  11.41)   46.23                70
 04/25/2023   23:51:23   (  70.03, 178.39) 04/25/2023   23:51:32  (  70.02, 178.33)    2.30                 9
 04/26/2023   00:42:05   ( -69.93, -14.15) 04/26/2023   00:41:02  ( -69.92, -14.19)    2.29                63