Simultaneous Nadir Overpasses (SNOs) between FY3D and LANDSAT-8
TLE Epoch: 2021 6 10.  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)
 06/10/2021   10:14:23   ( -71.67,-156.86) 06/10/2021   10:15:32  ( -71.58,-155.29)   55.96                69
 06/10/2021   11:04:57   (  71.05,  11.55) 06/10/2021   11:05:07  (  71.06,  11.50)    2.27                10
 06/10/2021   11:55:39   ( -71.01, 178.95) 06/10/2021   11:54:36  ( -70.99, 179.03)    3.27                63
 06/13/2021   03:21:17   (  71.11, 127.40) 06/13/2021   03:21:36  (  71.12, 127.47)    2.84                19
 06/13/2021   04:11:58   ( -71.00, -65.11) 06/13/2021   04:11:06  ( -71.00, -65.08)    1.20                52
 06/15/2021   19:37:35   (  71.11,-116.67) 06/15/2021   19:38:05  (  71.11,-116.65)    0.62                30
 06/15/2021   20:28:16   ( -71.01,  50.83) 06/15/2021   20:27:35  ( -71.00,  50.80)    1.35                41
 06/18/2021   11:53:54   (  71.12,  -0.74) 06/18/2021   11:54:35  (  71.11,  -0.78)    2.15                41
 06/18/2021   12:44:36   ( -71.06, 166.68) 06/18/2021   12:44:04  ( -71.05, 166.76)    3.03                32
 06/21/2021   04:10:13   (  71.13, 115.18) 06/21/2021   04:11:04  (  71.15, 115.16)    2.25                51
 06/21/2021   05:00:55   ( -71.06, -77.38) 06/21/2021   05:00:34  ( -71.04, -77.37)    2.51                21
 06/21/2021   05:51:22   (  70.08,  91.52) 06/21/2021   05:50:16  (  70.12,  88.88)   99.81                66
 06/23/2021   20:26:32   (  71.14,-128.90) 06/23/2021   20:27:34  (  71.13,-128.98)    3.15                62
 06/23/2021   21:17:14   ( -71.07,  38.55) 06/23/2021   21:17:03  ( -71.08,  38.57)    1.70                11