Simultaneous Nadir Overpasses (SNOs) between NOAA-21 and FY3D
TLE Epoch: 2022 12 5.  Predictions up to the next  14.0 days:

     Date     Time(NOAA-21) NOAA-21 Lat/Lon Date Time(FY3D) FY3D Lat/Lon    Distance(km)  Time Diff(sec)
 12/07/2022   04:57:10   ( -81.21,-132.61) 12/07/2022   04:55:56  ( -81.20,-132.45)    2.75                74
 12/07/2022   05:47:54   (  81.21,  34.74) 12/07/2022   05:46:43  (  81.20,  34.56)    3.02                71
 12/07/2022   06:38:20   ( -81.20,-157.72) 12/07/2022   06:37:27  ( -81.20,-157.54)    2.98                53
 12/07/2022   07:29:04   (  81.20,   9.63) 12/07/2022   07:28:14  (  81.20,   9.47)    2.72                50
 12/07/2022   08:19:31   ( -81.21, 176.80) 12/07/2022   08:18:59  ( -81.20, 176.98)    3.21                32
 12/07/2022   09:10:14   (  81.20, -15.48) 12/07/2022   09:09:45  (  81.20, -15.62)    2.47                29
 12/07/2022   10:00:41   ( -81.20, 151.69) 12/07/2022   10:00:31  ( -81.20, 151.50)    3.17                10
 12/07/2022   10:51:25   (  81.20, -40.97) 12/07/2022   10:51:17  (  81.20, -41.10)    2.18                 8
 12/07/2022   11:41:51   ( -81.20, 126.58) 12/07/2022   11:42:02  ( -81.20, 126.41)    2.94                11
 12/07/2022   12:32:35   (  81.20, -66.08) 12/07/2022   12:32:48  (  81.20, -66.19)    1.91                13
 12/07/2022   13:23:02   ( -81.20, 101.09) 12/07/2022   13:23:34  ( -81.20, 100.93)    2.75                32
 12/07/2022   14:13:46   (  81.20, -91.57) 12/07/2022   14:14:20  (  81.20, -91.67)    1.66                34
 12/07/2022   15:04:12   ( -81.20,  75.99) 12/07/2022   15:05:05  ( -81.20,  75.84)    2.49                53
 12/07/2022   15:54:56   (  81.20,-116.68) 12/07/2022   15:55:51  (  81.20,-116.76)    1.35                55