Simultaneous Nadir Overpasses (SNOs) between FY3D and LANDSAT-8
TLE Epoch: 2021 4 28.  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)
 04/28/2021   12:11:40   ( -71.15, 174.41) 04/28/2021   12:12:51  ( -71.16, 174.54)    4.56                71
 04/28/2021   13:02:23   (  71.02, -18.04) 04/28/2021   13:02:19  (  71.00, -18.06)    1.41                 4
 04/28/2021   13:53:03   ( -70.84, 149.57) 04/28/2021   13:51:49  ( -70.89, 149.40)    8.01                74
 05/01/2021   04:28:04   ( -71.38, -70.05) 05/01/2021   04:29:16  ( -71.29, -69.38)   26.43                72
 05/01/2021   05:18:43   (  71.04,  97.85) 05/01/2021   05:18:46  (  71.02,  97.85)    1.84                 3
 05/01/2021   06:09:24   ( -70.92, -94.62) 05/01/2021   06:08:16  ( -70.91, -94.69)    2.78                68
 05/03/2021   20:44:29   ( -71.67,  45.37) 05/03/2021   20:45:38  ( -71.57,  46.97)   56.99                69
 05/03/2021   21:35:03   (  71.06,-146.25) 05/03/2021   21:35:13  (  71.04,-146.25)    3.15                10
 05/03/2021   22:25:44   ( -70.94,  21.27) 05/03/2021   22:24:43  ( -70.92,  21.21)    3.07                61
 05/06/2021   13:00:54   ( -71.95, 160.78) 05/06/2021   13:02:00  ( -71.85, 163.32)   88.38                66
 05/06/2021   13:51:23   (  71.09, -30.36) 05/06/2021   13:51:39  (  71.10, -30.27)    3.13                16
 05/06/2021   14:42:04   ( -70.97, 137.17) 05/06/2021   14:41:09  ( -70.99, 137.19)    2.27                55
 05/09/2021   06:07:42   (  71.12,  85.53) 05/09/2021   06:08:05  (  71.10,  85.61)    3.51                23
 05/09/2021   06:58:23   ( -71.00,-106.94) 05/09/2021   06:57:35  ( -70.99,-106.92)    1.03                48
 05/11/2021   22:24:01   (  71.09,-158.49) 05/11/2021   22:24:32  (  71.09,-158.52)    0.88                31
 05/11/2021   23:14:42   ( -70.98,   9.03) 05/11/2021   23:14:02  ( -70.99,   8.96)    3.13                40