Simultaneous Nadir Overpasses (SNOs) between FY3D and LANDSAT-8
TLE Epoch: 2021 9 20.  Predictions up to the next  14.0 days:

     Date     Time(FY3D) FY3D Lat/Lon Date Time(LANDSAT-8) LANDSAT-8 Lat/Lon    Distance(km)  Time Diff(sec)
 09/20/2021   09:38:13   ( -71.34,-146.48) 09/20/2021   09:39:01  ( -71.32,-146.45)    1.93                48
 09/20/2021   10:28:57   (  71.23,  21.01) 09/20/2021   10:28:28  (  71.23,  21.05)    1.20                29
 09/23/2021   01:54:31   ( -71.34, -30.55) 09/23/2021   01:55:30  ( -71.34, -30.54)    0.65                59
 09/23/2021   02:45:15   (  71.24, 136.94) 09/23/2021   02:44:57  (  71.25, 136.95)    0.68                18
 09/23/2021   03:35:45   ( -70.57, -54.61) 09/23/2021   03:34:36  ( -70.64, -56.36)   65.11                69
 09/25/2021   18:10:49   ( -71.36,  85.38) 09/25/2021   18:11:59  ( -71.35,  85.37)    0.41                70
 09/25/2021   19:01:33   (  71.25,-107.13) 09/25/2021   19:01:26  (  71.26,-107.15)    0.67                 7
 09/25/2021   19:52:11   ( -71.00,  60.63) 09/25/2021   19:50:58  ( -71.03,  60.13)   18.42                73
 09/28/2021   10:27:12   ( -71.68,-159.26) 09/28/2021   10:28:23  ( -71.58,-158.38)   32.64                71
 09/28/2021   11:17:50   (  71.27,   8.79) 09/28/2021   11:17:54  (  71.26,   8.75)    1.58                 4
 09/28/2021   12:08:31   ( -71.17, 176.29) 09/28/2021   12:07:24  ( -71.15, 176.20)    3.42                67
 10/01/2021   02:43:37   ( -72.05, -44.01) 10/01/2021   02:44:45  ( -71.96, -41.85)   75.10                68
 10/01/2021   03:34:08   (  71.29, 124.71) 10/01/2021   03:34:23  (  71.27, 124.63)    3.33                15
 10/01/2021   04:24:50   ( -71.23, -67.88) 10/01/2021   04:23:52  ( -71.21, -67.82)    3.29                58
 10/03/2021   19:50:26   (  71.31,-119.38) 10/03/2021   19:50:51  (  71.32,-119.40)    1.69                25
 10/03/2021   20:41:07   ( -71.20,  48.12) 10/03/2021   20:40:21  ( -71.21,  48.06)    2.65                46