Simultaneous Nadir Overpasses (SNOs) between NPP and TERRA
TLE Epoch: 2017 9 21.  Predictions up to the next  14.0 days:

     Date     Time(NPP) NPP Lat/Lon Date Time(TERRA) TERRA Lat/Lon    Distance(km)  Time Diff(sec)
 09/21/2017   02:56:40   ( -68.41, -45.53) 09/21/2017   02:57:18  ( -68.40, -45.51)    1.19                38
 09/21/2017   03:47:24   (  68.28, 121.95) 09/21/2017   03:46:45  (  68.29, 122.00)    2.12                39
 09/23/2017   18:23:01   (  68.82, -97.62) 09/23/2017   18:24:12  (  68.75, -96.84)   32.40                71
 09/23/2017   19:13:36   ( -68.36,  70.30) 09/23/2017   19:13:47  ( -68.37,  70.32)    0.96                11
 09/23/2017   20:04:20   (  68.23,-122.22) 09/23/2017   20:03:14  (  68.25,-122.17)    2.91                66
 09/26/2017   10:39:50   (  68.40,  18.70) 09/26/2017   10:40:46  (  68.42,  18.64)    3.43                56
 09/26/2017   11:30:32   ( -68.32,-173.88) 09/26/2017   11:30:16  ( -68.32,-173.85)    1.23                16
 09/26/2017   12:21:02   (  67.49,  -5.53) 09/26/2017   12:19:53  (  67.59,  -7.06)   65.71                69
 09/29/2017   02:56:45   (  68.36, 134.52) 09/29/2017   02:57:14  (  68.37, 134.46)    2.59                29
 09/29/2017   03:47:27   ( -68.28, -58.06) 09/29/2017   03:46:44  ( -68.27, -58.03)    1.58                43
 10/01/2017   18:23:01   ( -68.67,  82.58) 10/01/2017   18:24:13  ( -68.60,  82.98)   17.69                72
 10/01/2017   19:13:41   (  68.33,-109.67) 10/01/2017   19:13:43  (  68.31,-109.73)    3.05                 2
 10/01/2017   20:04:23   ( -68.24,  57.76) 10/01/2017   20:03:13  ( -68.21,  57.79)    3.31                70
 10/04/2017   10:39:53   ( -68.42,-161.32) 10/04/2017   10:40:44  ( -68.42,-161.36)    1.58                51
 10/04/2017   11:30:37   (  68.29,   6.15) 10/04/2017   11:30:11  (  68.30,   6.14)    1.00                26
 10/04/2017   12:21:03   ( -67.35, 174.63) 10/04/2017   12:19:55  ( -67.42, 172.76)   80.67                68