Simultaneous Nadir Overpasses (SNOs) between NPP and TERRA
TLE Epoch: 2018 12 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)
 12/21/2018   02:56:34   (  68.32, 134.55) 12/21/2018   02:56:59  (  68.33, 134.56)    1.20                25
 12/21/2018   03:47:15   ( -68.18, -57.95) 12/21/2018   03:46:30  ( -68.17, -58.01)    2.77                45
 12/23/2018   18:22:48   ( -68.61,  82.63) 12/23/2018   18:23:59  ( -68.56,  83.07)   18.87                71
 12/23/2018   19:13:28   (  68.28,-109.63) 12/23/2018   19:13:29  (  68.29,-109.62)    0.72                 1
 12/23/2018   20:04:09   ( -68.14,  57.87) 12/23/2018   20:03:00  ( -68.12,  57.82)    2.56                69
 12/26/2018   10:39:38   ( -68.36,-161.27) 12/26/2018   10:40:32  ( -68.35,-161.31)    2.16                54
 12/26/2018   11:30:22   (  68.25,   6.18) 12/26/2018   11:29:59  (  68.23,   6.20)    1.54                23
 12/26/2018   12:20:50   ( -67.40, 174.55) 12/26/2018   12:19:41  ( -67.46, 172.94)   69.15                69
 12/29/2018   02:06:08   (  69.44, 145.72) 12/29/2018   02:07:14  (  69.34, 148.19)   97.26                66
 12/29/2018   02:56:31   ( -68.32, -45.45) 12/29/2018   02:57:00  ( -68.34, -45.43)    2.79                29
 12/29/2018   03:47:14   (  68.16, 122.07) 12/29/2018   03:46:28  (  68.17, 122.01)    3.08                46
 12/31/2018   18:22:46   (  68.55, -97.29) 12/31/2018   18:23:58  (  68.49, -97.01)   13.15                72
 12/31/2018   19:13:25   ( -68.28,  70.37) 12/31/2018   19:13:30  ( -68.28,  70.37)    0.58                 5
 12/31/2018   20:04:09   (  68.18,-122.19) 12/31/2018   20:02:57  (  68.16,-122.13)    3.16                72
 01/03/2019   10:39:37   (  68.35,  18.73) 01/03/2019   10:40:29  (  68.35,  18.71)    0.91                52
 01/03/2019   11:30:19   ( -68.25,-173.81) 01/03/2019   11:29:59  ( -68.26,-173.77)    2.08                20
 01/03/2019   12:20:48   (  67.33,  -5.38) 01/03/2019   12:19:40  (  67.35,  -7.17)   76.63                68