Author: Pierre Lauber ILRS Combined Range Bias Report 1 ********************************* 2026-05-30 00:00 UT - 2026-06-09 00:00 UT Compiled by: SLR Observatory Zimmerwald Date : 2026-06-09 12:30 UT E-Mail : pierre.lauber@unibe.ch --------------------------------------------------------------------------------- 1874 MDVS Mendeleevo DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 1874 2026-06-04 09:06 LAG2 532 -1 2 -9 3 --------------------------------------------------------------------------------- 1874 Average 532 -1 2 -9 3 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 1891 DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 1891 2026-06-01 10:47 LAG1 532 -21 3 --------------------------------------------------------------------------------- 1891 Average 532 -21 3 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7090 YARL Yarragadee DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7090 2026-05-30 12:02 LAG2 532 11 1 2 2 7090 2026-05-30 12:46 LAG1 532 -21 2 -35 3 7090 2026-05-31 10:07 LAG2 532 13 1 17 2 7090 2026-05-31 14:16 LAG2 532 0 1 2 2 7090 2026-05-31 14:37 LAG1 532 -5 2 25 3 7090 2026-05-31 18:11 LAG2 532 -7 2 -2 1 7090 2026-06-01 07:59 LAG2 532 10 3 11 4 7090 2026-06-01 12:10 LAG2 532 -10 1 3 1 7090 2026-06-01 13:27 LAG1 532 5 1 9 3 7090 2026-06-01 16:28 LAG2 532 0 1 5 3 7090 2026-06-01 16:38 LAG1 532 -6 4 9 4 7090 2026-06-01 19:57 LAG1 532 7 4 26 4 7090 2026-06-02 06:11 LAG2 532 14 2 23 3 7090 2026-06-02 11:58 LAG1 532 6 2 5 3 7090 2026-06-02 14:10 LAG2 532 * * * * 7090 2026-06-02 15:23 LAG1 532 6 1 -13 2 7090 2026-06-02 18:33 LAG2 532 8 2 -3 3 7090 2026-06-02 18:38 LAG1 532 * * * * 7090 2026-06-02 22:22 LAG1 532 1 2 -20 3 7090 2026-06-03 08:19 LAG2 532 14 2 6 3 7090 2026-06-03 10:35 LAG1 532 9 2 -9 2 7090 2026-06-03 12:31 LAG2 532 4 1 0 2 7090 2026-06-03 14:09 LAG1 532 5 2 24 2 7090 2026-06-03 16:43 LAG2 532 3 1 2 2 7090 2026-06-03 17:23 LAG1 532 2 2 2 3 7090 2026-06-03 20:43 LAG1 532 3 3 -18 4 7090 2026-06-04 00:10 LAG1 532 -1 1 30 3 7090 2026-06-04 06:15 LAG2 532 2 2 -1 5 7090 2026-06-04 10:32 LAG2 532 10 2 -7 3 7090 2026-06-04 12:47 LAG1 532 2 1 31 4 7090 2026-06-04 14:42 LAG2 532 -3 1 -15 3 7090 2026-06-04 18:55 LAG2 532 4 2 45 4 7090 2026-06-04 19:16 LAG1 532 21 1 -84 1 7090 2026-06-04 23:07 LAG1 532 -1 2 47 3 7090 2026-06-05 04:24 LAG2 532 9 1 2 2 7090 2026-06-05 11:45 LAG1 532 28 2 35 2 7090 2026-06-05 12:47 LAG2 532 2 1 0 2 7090 2026-06-05 14:57 LAG1 532 5 2 -2 2 7090 2026-06-05 16:53 LAG2 532 9 1 11 1 7090 2026-06-05 21:30 LAG1 532 12 2 7 2 7090 2026-06-06 06:48 LAG2 532 0 2 -9 3 7090 2026-06-06 09:55 LAG1 532 15 1 5 4 7090 2026-06-06 10:49 LAG2 532 5 2 0 3 7090 2026-06-06 13:28 LAG1 532 9 2 24 4 7090 2026-06-06 15:01 LAG2 532 6 1 3 2 7090 2026-06-06 23:56 LAG1 532 8 2 -9 2 7090 2026-06-07 04:31 LAG2 532 12 2 16 3 7090 2026-06-07 08:52 LAG2 532 7 1 -14 3 7090 2026-06-07 12:14 LAG1 532 12 2 13 4 7090 2026-06-07 13:00 LAG2 532 4 1 -6 2 7090 2026-06-07 22:14 LAG1 532 9 2 -3 5 7090 2026-06-08 06:47 LAG2 532 7 3 --------------------------------------------------------------------------------- 7090 Average 532 5 1 5 2 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7105 GODL Greenbelt DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7105 2026-06-01 09:56 LAG2 532 5 1 -13 2 7105 2026-06-02 01:25 LAG1 532 -6 3 -21 3 7105 2026-06-02 08:08 LAG2 532 9 3 4 3 7105 2026-06-02 16:21 LAG2 532 4 7 -14 3 7105 2026-06-03 06:18 LAG2 532 1 2 7 3 7105 2026-06-03 10:16 LAG2 532 24 3 1 7 7105 2026-06-03 12:20 LAG1 532 16 5 -8 5 7105 2026-06-03 15:47 LAG1 532 12 2 24 2 7105 2026-06-03 22:22 LAG1 532 -2 3 -24 3 7105 2026-06-04 08:17 LAG2 532 12 1 -4 3 7105 2026-06-04 14:39 LAG1 532 5 2 41 0 7105 2026-06-05 06:27 LAG2 532 7 1 -1 4 7105 2026-06-05 23:23 LAG1 532 -6 1 -23 2 7105 2026-06-08 08:48 LAG2 532 -1 2 --------------------------------------------------------------------------------- 7105 Average 532 5 2 -2 3 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7110 MONL Monument Peak DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7110 2026-06-03 00:03 LAG1 532 -1 2 * * 7110 2026-06-03 03:31 LAG1 532 -5 2 -11 3 7110 2026-06-03 22:40 LAG1 532 * * * * 7110 2026-06-04 02:11 LAG1 532 1 2 -11 3 7110 2026-06-05 00:46 LAG1 532 3 2 -9 2 7110 2026-06-05 16:54 LAG1 532 -4 2 -17 4 7110 2026-06-05 18:31 LAG2 532 6 2 -1 3 --------------------------------------------------------------------------------- 7110 Average 532 0 2 -9 3 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7119 HA4T Haleakala DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7119 2026-06-03 19:59 LAG1 532 14 1 36 4 7119 2026-06-07 18:06 LAG1 532 -4 2 -11 3 7119 2026-06-07 18:28 LAG2 532 3 1 6 2 7119 2026-06-08 20:07 LAG1 532 -3 3 7119 2026-06-08 20:38 LAG2 532 14 3 --------------------------------------------------------------------------------- 7119 Average 532 4 2 10 3 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7249 BEIL Beijing DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7249 2026-06-06 15:46 LAG2 532 -41 4 -54 2 7249 2026-06-06 19:23 LAG2 532 -14 5 7249 2026-06-07 13:06 LAG1 532 -30 6 -30 5 7249 2026-06-07 17:36 LAG2 532 -23 4 -8 4 --------------------------------------------------------------------------------- 7249 Average 532 -31 4 -26 4 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7306 DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7306 2026-06-01 10:26 LAG1 532 -30 1 -21 4 7306 2026-06-06 10:24 LAG1 532 -45 1 -25 1 --------------------------------------------------------------------------------- 7306 Average 532 -37 1 -23 2 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7396 DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7396 2026-05-30 13:07 LAG1 532 22 1 --------------------------------------------------------------------------------- 7396 Average 532 22 1 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7501 HARL Hartebeesthoek DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7501 2026-05-31 18:33 LAG1 532 4 5 24 7 7501 2026-06-01 17:15 LAG1 532 9 3 -1 5 7501 2026-06-01 19:59 LAG2 532 -2 2 20 3 7501 2026-06-02 22:29 LAG2 532 28 1 -5 5 7501 2026-06-03 02:09 LAG1 532 * * * * 7501 2026-06-04 18:24 LAG2 532 -2 1 -57 5 7501 2026-06-05 18:44 LAG1 532 0 1 -6 3 7501 2026-06-05 20:34 LAG2 532 -9 2 -15 3 --------------------------------------------------------------------------------- 7501 Average 532 4 2 -5 4 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7810 ZIML Zimmerwald DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7810 2026-05-30 02:17 LAG2 532 2 2 -1 2 7810 2026-05-30 20:53 LAG1 532 16 1 -19 6 7810 2026-05-31 00:31 LAG2 532 7 0 -9 1 7810 2026-06-01 11:15 LAG1 532 125 13 10 3 7810 2026-06-01 14:28 LAG1 532 4 1 13 2 7810 2026-06-07 17:05 LAG1 532 9 0 17 1 7810 2026-06-07 20:29 LAG1 532 11 1 1 2 7810 2026-06-08 01:24 LAG2 532 10 1 7810 2026-06-08 08:32 LAG1 532 16 2 7810 2026-06-08 09:39 LAG2 532 -1 6 --------------------------------------------------------------------------------- 7810 Average 532 19 2 1 2 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7817 DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7817 2026-06-01 02:39 LAG2 1064 13 2 -6 2 7817 2026-06-02 16:33 LAG1 1064 13 5 -12 4 7817 2026-06-02 19:50 LAG1 1064 -5 1 28 2 7817 2026-06-03 15:04 LAG1 1064 10 1 7817 2026-06-03 18:25 LAG1 1064 18 1 7817 2026-06-04 00:54 LAG2 532 -22 0 23 2 7817 2026-06-04 04:35 LAG2 532 37 1 -8 1 7817 2026-06-05 19:36 LAG1 1064 5 1 7817 2026-06-06 13:17 LAG2 1064 9 1 7817 2026-06-06 17:56 LAG1 1064 4 4 7817 2026-06-07 16:43 LAG1 1064 8 1 5 3 --------------------------------------------------------------------------------- 7817 Average 1064 8 1 3 2 7817 Average 532 7 0 7 1 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7819 DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7819 2026-05-31 18:43 LAG2 532 28 3 2 3 7819 2026-06-01 14:07 LAG1 532 35 4 4 2 7819 2026-06-01 21:08 LAG2 532 23 3 37 2 7819 2026-06-02 12:33 LAG1 532 34 4 41 4 7819 2026-06-02 19:03 LAG2 532 22 4 35 5 7819 2026-06-03 14:37 LAG1 532 24 3 49 4 7819 2026-06-04 13:11 LAG1 532 17 1 96 8 7819 2026-06-06 14:08 LAG1 532 21 6 30 6 7819 2026-06-06 19:19 LAG2 532 39 2 53 2 7819 2026-06-07 12:59 LAG1 532 15 4 21 5 7819 2026-06-07 17:43 LAG2 532 30 2 27 3 --------------------------------------------------------------------------------- 7819 Average 532 26 3 35 4 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7821 SHA2 Shanghai2 DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7821 2026-05-30 16:48 LAG2 532 -14 1 -23 2 7821 2026-06-01 03:12 LAG2 532 4 1 -5 1 7821 2026-06-01 10:30 LAG1 532 -18 1 -2 4 7821 2026-06-01 17:12 LAG2 532 29 1 1 1 --------------------------------------------------------------------------------- 7821 Average 532 0 1 -7 2 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7824 SFEL San Fernando DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7824 2026-06-02 20:11 LAG1 532 -39 1 -4 3 7824 2026-06-04 00:35 LAG2 532 -50 2 7 5 7824 2026-06-04 20:47 LAG1 532 -39 0 113 2 7824 2026-06-06 00:57 LAG2 532 -42 1 -15 2 7824 2026-06-08 00:57 LAG2 532 -22 1 --------------------------------------------------------------------------------- 7824 Average 532 -38 1 25 3 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7839 GRZL Graz DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7839 2026-06-02 06:00 LAG1 532 0 1 7 1 7839 2026-06-02 08:41 LAG2 532 -1 0 -4 1 7839 2026-06-02 12:54 LAG1 532 -6 1 -4 1 --------------------------------------------------------------------------------- 7839 Average 532 -2 0 0 1 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7840 HERL Herstmonceux DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7840 2026-06-02 12:39 LAG2 532 0 1 -12 2 7840 2026-06-02 13:11 LAG1 532 -5 1 -9 1 7840 2026-06-02 20:16 LAG1 532 6 2 11 2 7840 2026-06-05 05:38 LAG1 532 0 2 2 2 7840 2026-06-05 06:51 LAG2 532 4 1 -6 1 7840 2026-06-05 16:07 LAG1 532 -5 1 -8 2 7840 2026-06-08 18:54 LAG1 532 -6 1 --------------------------------------------------------------------------------- 7840 Average 532 0 1 -3 1 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7841 POT3 Potsdam DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7841 2026-05-31 04:17 LAG2 532 -4 1 -5 1 7841 2026-05-31 05:13 LAG1 532 5 1 -11 3 7841 2026-05-31 08:19 LAG2 532 3 2 -3 3 7841 2026-06-02 06:03 LAG1 532 6 2 7841 2026-06-03 18:47 LAG1 532 23 18 15 2 7841 2026-06-04 06:44 LAG1 532 0 1 -3 3 7841 2026-06-05 16:00 LAG1 532 30 42 0 3 --------------------------------------------------------------------------------- 7841 Average 532 9 9 -1 2 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7845 GRSM Grasse DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7845 2026-05-30 02:23 LAG2 532 -15 2 -15 2 7845 2026-05-30 06:20 LAG2 532 -2 2 -10 3 7845 2026-06-04 08:58 LAG2 532 -2 2 -14 3 7845 2026-06-05 02:44 LAG2 532 -13 2 -12 2 7845 2026-06-05 09:01 LAG1 532 -8 4 -24 4 7845 2026-06-08 08:48 LAG1 532 -8 2 7845 2026-06-08 09:22 LAG2 532 -5 4 7845 2026-06-08 12:02 LAG1 532 8 4 7845 2026-06-08 13:26 LAG2 532 5 4 7845 2026-06-08 15:30 LAG1 532 3 3 --------------------------------------------------------------------------------- 7845 Average 532 -3 2 -15 2 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 7941 MATM Matera DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 7941 2026-05-30 02:16 LAG2 532 -10 1 -9 2 7941 2026-05-30 06:13 LAG2 532 3 1 -1 1 7941 2026-05-30 06:47 LAG1 532 6 2 -5 2 7941 2026-05-30 13:40 LAG1 532 -16 2 -21 3 7941 2026-05-30 16:51 LAG1 532 -20 2 26 3 7941 2026-05-31 00:27 LAG2 532 -9 1 -19 1 7941 2026-05-31 04:27 LAG2 532 -5 1 -5 2 7941 2026-05-31 05:33 LAG1 532 2 1 -14 6 7941 2026-05-31 08:29 LAG2 532 0 1 -4 1 7941 2026-05-31 08:53 LAG1 532 -4 1 -39 6 7941 2026-05-31 15:42 LAG1 532 -18 4 -35 5 7941 2026-06-01 02:48 LAG2 532 -4 1 -4 2 7941 2026-06-01 06:23 LAG2 532 -2 1 -10 3 7941 2026-06-01 07:23 LAG1 532 -24 2 -19 2 7941 2026-06-01 17:47 LAG1 532 2 3 -16 3 7941 2026-06-02 06:14 LAG1 532 -1 2 2 2 7941 2026-06-02 16:33 LAG1 532 -2 0 5 1 7941 2026-06-03 02:52 LAG2 532 -7 3 0 1 7941 2026-06-03 04:53 LAG1 532 -5 1 -6 1 7941 2026-06-03 08:20 LAG1 532 0 2 2 3 7941 2026-06-03 18:40 LAG1 532 3 2 14 3 7941 2026-06-04 07:08 LAG1 532 -2 2 -3 4 7941 2026-06-04 10:28 LAG1 532 5 3 -3 6 7941 2026-06-04 17:20 LAG1 532 -6 1 16 2 7941 2026-06-05 05:48 LAG1 532 -2 2 -1 3 7941 2026-06-05 06:59 LAG2 532 2 1 -3 1 7941 2026-06-05 09:02 LAG1 532 -3 1 -17 2 7941 2026-06-05 15:56 LAG1 532 -7 2 -7 2 7941 2026-06-06 05:19 LAG2 532 -1 2 6 3 7941 2026-06-06 07:51 LAG1 532 -5 2 -3 3 7941 2026-06-06 09:08 LAG2 532 9 2 12 3 7941 2026-06-06 14:35 LAG1 532 -7 1 18 3 7941 2026-06-06 18:09 LAG1 532 * * * * 7941 2026-06-06 23:11 LAG2 532 1 4 -11 3 7941 2026-06-07 06:22 LAG1 532 -7 1 -3 2 7941 2026-06-08 05:26 LAG2 532 -5 1 7941 2026-06-08 08:33 LAG1 532 -3 2 7941 2026-06-08 15:26 LAG1 532 1 0 7941 2026-06-08 23:28 LAG2 532 -5 1 --------------------------------------------------------------------------------- 7941 Average 532 -3 1 -4 2 --------------------------------------------------------------------------------- --------------------------------------------------------------------------------- 8834 WETL Wettzell DGFI MCC HIT-U SAO JCET sat wl rb pr rb pr rb pr rb pr rb pr --------------------------------------------------------------------------------- 8834 2026-05-31 04:21 LAG2 532 -1 1 -11 2 8834 2026-05-31 04:22 LAG2 1064 -9 0 -17 1 8834 2026-06-01 14:38 LAG1 1064 -17 1 -2 1 8834 2026-06-02 00:39 LAG2 1064 -5 1 16 1 8834 2026-06-02 00:41 LAG2 532 7 2 23 5 8834 2026-06-02 06:22 LAG1 1064 2 1 1 2 8834 2026-06-02 16:49 LAG1 1064 -1 1 6 3 8834 2026-06-03 15:25 LAG1 1064 -16 2 -10 3 8834 2026-06-03 18:57 LAG1 532 * * * * 8834 2026-06-03 18:59 LAG1 1064 8 0 6 2 8834 2026-06-04 00:48 LAG2 1064 -18 1 7 3 8834 2026-06-04 00:48 LAG2 532 -14 1 8 3 8834 2026-06-04 04:38 LAG2 1064 -1 1 -23 1 8834 2026-06-04 04:38 LAG2 532 3 1 -22 2 8834 2026-06-04 07:09 LAG1 532 -6 1 -16 2 8834 2026-06-04 07:09 LAG1 1064 -6 1 -13 3 8834 2026-06-05 11:06 LAG2 1064 * * * * 8834 2026-06-05 15:51 LAG1 532 -6 2 -5 1 8834 2026-06-05 16:02 LAG1 1064 -3 1 -4 1 8834 2026-06-06 01:00 LAG2 1064 -11 1 1 2 8834 2026-06-06 01:00 LAG2 532 -4 3 -2 4 8834 2026-06-06 04:04 LAG1 1064 -12 1 -25 1 8834 2026-06-06 04:05 LAG1 532 -13 1 -29 1 8834 2026-06-06 05:00 LAG2 532 3 1 8 2 8834 2026-06-06 05:00 LAG2 1064 -2 1 8 1 8834 2026-06-06 07:58 LAG1 1064 -4 3 -9 2 8834 2026-06-06 07:58 LAG1 532 -1 2 -8 2 8834 2026-06-07 06:14 LAG1 1064 * * * * 8834 2026-06-07 07:13 LAG2 532 4 1 8 2 8834 2026-06-07 07:14 LAG2 1064 -6 0 1 2 8834 2026-06-07 16:48 LAG1 1064 -1 1 5 3 8834 2026-06-07 16:53 LAG1 532 -8 2 1 2 8834 2026-06-08 01:07 LAG2 532 9 3 8834 2026-06-08 01:07 LAG2 1064 15 2 8834 2026-06-08 04:49 LAG1 1064 2 1 8834 2026-06-08 05:06 LAG2 1064 1 3 8834 2026-06-08 05:07 LAG2 532 -10 1 8834 2026-06-08 08:20 LAG1 1064 2 2 8834 2026-06-08 09:24 LAG2 1064 -5 2 8834 2026-06-08 11:58 LAG1 532 6 1 8834 2026-06-08 12:03 LAG1 1064 8 1 --------------------------------------------------------------------------------- 8834 Average 532 -2 1 -3 2 8834 Average 1064 -3 1 -3 1 --------------------------------------------------------------------------------- sc : Satellite wl : Wavelength (nm) rb : Range bias (mm) pr : Precision estimate (mm) * : Processed but no value given ***** : Format overflow Average: Averages of range biases and precision estimates (outliers rejected) DGFI : Deutsches Geodaetisches Forschungsinstitut (Munich) MCC : Mission Control Center (Moscow) HIT-U : Hitotsubashi University (Kunitachi, Tokyo) SAO : Shanghai Astronomical Observatory JCET : Joint Center for Earth System Technology, UMBC/GSFC LAG1 : Lageos1 LAG2 : Lageos2