PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT PUBLICATION_DATE = 2011-11-10 INTERCHANGE_FORMAT = ASCII NOTE = "Explanation of time-related issues in MER archives." END_OBJECT = TEXT END MER Time Tag Issues Boris Semenov, NAIF July 29, 2004 Revised January 21, 2005; July 27, 2005; and November 10, 2011. MER Time Tag Issues =========================================================================== This document summarizes a number of issues related to various types of time tags used in the archived MER science data products. Error in On-board Clock Correlation -------------------------------------------------------- The official rover on-board clock correlation to UTC used in operations and for science archive preparation is incorrect in an absolute sense by as much as 20 seconds during some periods. The error stems from a combinations of reasons: the rover generated too few time correlation packets, the specifics of the process used to derive the correlation function, and the requirement for backward compatibility between correlation versions imposed by the ground system tools. Until an improved version of the on-board clock correlation becomes available and science product labels are regenerated using it, these tables providing on-board clock time, the corresponding UTC computed using the official correlation, and the correction, in seconds, to be added to the UTC computed using the official correlation, can be used to compensate for the error in the UTC time tags attached to the science data products. Linear interpolation can be used to estimate a correction value between the table points. MER-1 On-board Clock Correlation Correction table: SCLK UTC Correction ------------- ------------------- ------------ 122714000.000 2003-11-21T19:12:10 0.00000000 128538000.000 2004-01-28T04:58:47 0.35045579 128539000.000 2004-01-28T05:15:27 0.00000000 129171000.000 2004-02-04T12:48:47 6.03954345 129172000.000 2004-02-04T13:05:33 0.00000000 129521000.000 2004-02-08T14:02:17 -0.07783715 129522000.000 2004-02-08T14:18:56 0.00000000 129881000.000 2004-02-12T18:02:20 -0.74451666 129882000.000 2004-02-12T18:18:59 0.00000000 131747000.000 2004-03-05T08:22:30 -2.78524545 131748000.000 2004-03-05T08:39:07 0.00000000 137232000.000 2004-05-07T19:59:27 -21.78271598 137233000.000 2004-05-07T20:15:45 0.00000000 143539000.000 2004-07-19T19:55:34 -23.00951022 143540000.000 2004-07-19T20:11:51 0.00000000 147623000.000 2004-09-05T02:21:28 3.86354187 147624000.000 2004-09-05T02:38:12 0.00000000 154017000.000 2004-11-18T02:27:44 20.39812636 154018000.000 2004-11-18T02:44:45 0.00000000 154195000.000 2004-11-20T03:54:45 2.34983149 154196000.000 2004-11-20T04:11:27 0.00000000 161118000.000 2005-02-08T06:58:25 -18.98187968 161119000.000 2005-02-08T07:14:46 0.00000000 166353000.000 2005-04-09T21:08:06 8.60842806 166354000.000 2005-04-09T21:24:54 -0.00000018 166709000.000 2005-04-14T00:01:35 0.57460395 166710000.000 2005-04-14T00:18:16 0.00000000 173012000.000 2005-06-25T22:51:48 -6.22226176 173018000.000 2005-06-26T00:31:42 0.00000000 181002000.000 2005-09-26T10:18:13 4.53608921 181007000.000 2005-09-26T11:41:37 0.00000000 188370000.000 2005-12-20T16:58:15 1.38713756 188371000.000 2005-12-20T17:14:56 0.00000000 189345705.000 2006-01-01T00:00:00 0.00000000 189345706.000 2006-01-01T00:00:01 0.00000000 193963000.000 2006-02-23T10:34:54 -8.43994325 193964000.000 2006-02-23T10:51:25 0.00000000 196626000.000 2006-03-26T06:17:58 -4.96033761 196627000.000 2006-03-26T06:34:33 0.00000000 199468000.000 2006-04-28T03:44:19 -5.28525761 199469000.000 2006-04-28T04:00:54 0.00000000 203374000.000 2006-06-12T08:43:47 -4.97687453 203375000.000 2006-06-12T09:00:22 0.00000000 217756000.000 2006-11-25T19:41:40 20.27407622 217757000.000 2006-11-25T19:58:40 0.00000000 222110000.000 2007-01-15T05:08:13 19.62975746 222111000.000 2007-01-15T05:25:13 0.00000000 226899000.000 2007-03-11T15:25:05 11.96720260 226900000.000 2007-03-11T15:41:57 0.00000000 244032000.000 2007-09-25T22:35:30 -59.67531273 244033000.000 2007-09-25T22:51:11 0.00000000 247851000.000 2007-11-09T03:23:59 42.28924274 247852000.000 2007-11-09T03:41:21 0.00000000 252912000.000 2008-01-06T17:14:48 -31.12214941 252913000.000 2008-01-06T17:30:56 0.00000000 265428000.000 2008-05-30T13:53:34 -60.67674863 265429000.000 2008-05-30T14:09:13 0.00000000 279107000.000 2008-11-04T21:33:55 23.74390805 279108000.000 2008-11-04T21:50:59 0.00000000 287532000.000 2009-02-10T09:50:19 27.84562874 287533000.000 2009-02-10T10:07:27 0.00000000 298018000.000 2009-06-11T18:37:22 -32.36750197 298019000.000 2009-06-11T18:53:30 0.00000000 319049000.000 2010-02-10T04:32:05 -40.28406036 319050000.000 2010-02-10T04:48:05 0.00000000 328462000.000 2010-05-30T03:13:42 -38.98414707 328463000.000 2010-05-30T03:29:43 0.00000000 336804000.000 2010-09-03T16:25:03 13.90489197 336805000.000 2010-09-03T16:41:57 0.00000000 342100000.000 2010-11-03T23:31:34 5.20044577 342101000.000 2010-11-03T23:48:19 0.00000000 347018000.000 2010-12-30T21:38:04 11.88257134 347019000.000 2010-12-30T21:54:56 0.00000000 356600000.000 2011-04-20T19:18:22 -31.46133119 356601000.000 2011-04-20T19:34:31 0.00000000 MER-2 On-board Clock Correlation Correction table: SCLK UTC Correction ------------- ------------------- ------------ 126091000.000 2003-12-30T21:15:07 0.00000000 127259000.000 2004-01-13T09:41:45 5.31779034 127260000.000 2004-01-13T09:58:31 0.00000000 129032000.000 2004-02-02T22:12:09 -3.41549060 129033000.000 2004-02-02T22:28:46 0.00000000 130349000.000 2004-02-18T04:02:16 -0.90037587 130350000.000 2004-02-18T04:18:56 0.00000000 130793000.000 2004-02-23T07:22:19 -1.16488062 130794000.000 2004-02-23T07:38:58 0.00000000 133470000.000 2004-03-25T06:59:09 -4.57467157 133471000.000 2004-03-25T07:15:45 0.00000000 134539000.000 2004-04-06T15:55:47 -2.56826568 134540000.000 2004-04-06T16:12:24 0.00000000 137118000.000 2004-05-06T12:19:03 -7.99848235 137119000.000 2004-05-06T12:35:35 0.00000000 138620000.000 2004-05-23T21:32:10 -7.62354127 138621000.000 2004-05-23T21:48:42 0.00000000 144743000.000 2004-08-02T18:21:11 -18.77159578 144744000.000 2004-08-02T18:37:32 0.00000000 161963000.000 2005-02-18T01:37:36 12.00370592 161964000.000 2005-02-18T01:54:28 0.00000000 163650000.000 2005-03-09T14:14:11 6.30416778 163651000.000 2005-03-09T14:30:58 0.00000000 166225000.000 2005-04-08T09:30:42 26.56784931 166226000.000 2005-04-08T09:47:48 0.00000000 167734000.000 2005-04-25T20:41:15 2.39826447 167735000.000 2005-04-25T20:57:57 0.00000000 181313000.000 2005-09-30T00:39:07 8.44620439 181318000.000 2005-09-30T02:02:35 0.00000000 188325000.000 2005-12-20T04:26:36 -10.97230372 188326000.000 2005-12-20T04:43:05 0.00000000 189345813.000 2006-01-01T00:00:00 0.00000000 189345814.000 2006-01-01T00:00:01 0.00000000 193297000.000 2006-02-15T17:33:16 -26.84156373 193298000.000 2006-02-15T17:49:29 0.00000000 201200000.000 2006-05-18T04:48:54 -53.50781852 201201000.000 2006-05-18T05:04:41 0.00000000 206882000.000 2006-07-22T23:06:58 -12.18677679 206883000.000 2006-07-22T23:23:26 0.00000000 219219000.000 2006-12-12T18:00:43 6.83766875 219220000.000 2006-12-12T18:17:30 0.00000000 221084000.000 2007-01-03T08:03:46 1.80669975 221085000.000 2007-01-03T08:20:28 0.00000000 228189000.000 2007-03-26T13:39:05 34.90978691 228190000.000 2007-03-26T13:56:19 0.00000000 233073000.000 2007-05-22T02:19:06 19.45480382 233074000.000 2007-05-22T02:36:06 0.00000000 243458000.000 2007-09-19T07:02:17 -18.62140173 243459000.000 2007-09-19T07:18:38 0.00000000 252603000.000 2008-01-03T03:18:01 6.69929239 252604000.000 2008-01-03T03:34:48 0.00000000 258905000.000 2008-03-16T01:51:07 -106.78366995 258906000.000 2008-03-16T02:06:00 0.00000000 278258000.000 2008-10-26T01:34:12 50.01633453 278259000.000 2008-10-26T01:51:42 0.00000000 289178000.000 2009-03-01T10:52:34 24.63962740 289179000.000 2009-03-01T11:09:39 0.00000000 300721000.000 2009-07-13T01:14:50 85.36628681 300722000.000 2009-07-13T01:32:55 0.00000000 310573000.000 2009-11-04T01:57:09 -61.83415705 310574000.000 2009-11-04T02:12:47 0.00000000 319185000.000 2010-02-11T18:08:32 -45.57725817 319186000.000 2010-02-11T18:24:26 0.00000000 True Local Solar Time vs. Hybrid Solar Local Time -------------------------------------------------------- For surface operations the MER project adopted a Hybrid Local Solar Time (HLST) time system as the Mars local time system to be used in sequencing and planning. HLST was introduced as a replacement of the True Local Solar Time (TLST) because a time system with a constant duration of a second was needed. The HLST is essentially a linear approximation of the true local time with the rate set equal to the mean Mars local second duration and the initial reference point set to make sure that HLST deviates from TLST by no more that 15 local minutes during the primary mission. This approximation continued to deviate from the TLST as the surface operations went on, reaching over 50 local minutes difference by the end of the extended mission. The tables below illustrate the difference between TLST and HLST. MER-1 TLST vs. HLST table True LST Hybrid LST ----------------- ----------------- SOL-0001-12:00:00 SOL-0001-12:11:04 SOL-0010-12:00:00 SOL-0010-12:09:46 SOL-0020-12:00:00 SOL-0020-12:07:48 SOL-0030-12:00:00 SOL-0030-12:05:23 SOL-0040-12:00:00 SOL-0040-12:02:35 SOL-0050-12:00:00 SOL-0050-11:59:29 SOL-0060-12:00:00 SOL-0060-11:56:09 SOL-0070-12:00:00 SOL-0070-11:52:38 SOL-0080-12:00:00 SOL-0080-11:49:01 SOL-0090-12:00:00 SOL-0090-11:45:20 SOL-0100-12:00:00 SOL-0100-11:41:39 SOL-0110-12:00:00 SOL-0110-11:38:00 SOL-0120-12:00:00 SOL-0120-11:34:26 SOL-0130-12:00:00 SOL-0130-11:31:00 SOL-0140-12:00:00 SOL-0140-11:27:42 SOL-0150-12:00:00 SOL-0150-11:24:34 SOL-0160-12:00:00 SOL-0160-11:21:38 SOL-0170-12:00:00 SOL-0170-11:18:54 SOL-0180-12:00:00 SOL-0180-11:16:23 SOL-0190-12:00:00 SOL-0190-11:14:05 SOL-0200-12:00:00 SOL-0200-11:11:58 SOL-0210-12:00:00 SOL-0210-11:10:03 SOL-0220-12:00:00 SOL-0220-11:08:19 SOL-0230-12:00:00 SOL-0230-11:06:42 SOL-0240-12:00:00 SOL-0240-11:05:13 SOL-0250-12:00:00 SOL-0250-11:03:49 SOL-0260-12:00:00 SOL-0260-11:02:29 SOL-0270-12:00:00 SOL-0270-11:01:10 SOL-0280-12:00:00 SOL-0280-10:59:50 SOL-0290-12:00:00 SOL-0290-10:58:30 SOL-0300-12:00:00 SOL-0300-10:57:06 SOL-0310-12:00:00 SOL-0310-10:55:40 SOL-0320-12:00:00 SOL-0320-10:54:10 SOL-0330-12:00:00 SOL-0330-10:52:37 SOL-0340-12:00:00 SOL-0340-10:51:01 SOL-0350-12:00:00 SOL-0350-10:49:24 SOL-0360-12:00:00 SOL-0360-10:47:48 SOL-0370-12:00:00 SOL-0370-10:46:15 SOL-0380-12:00:00 SOL-0380-10:44:48 SOL-0390-12:00:00 SOL-0390-10:43:29 SOL-0400-12:00:00 SOL-0400-10:42:23 SOL-0410-12:00:00 SOL-0410-10:41:34 SOL-0420-12:00:00 SOL-0420-10:41:05 SOL-0430-12:00:00 SOL-0430-10:41:02 SOL-0440-12:00:00 SOL-0440-10:41:28 SOL-0450-12:00:00 SOL-0450-10:42:29 SOL-0460-12:00:00 SOL-0460-10:44:10 SOL-0470-12:00:00 SOL-0470-10:46:32 SOL-0480-12:00:00 SOL-0480-10:49:39 SOL-0490-12:00:00 SOL-0490-10:53:34 SOL-0500-12:00:00 SOL-0500-10:58:15 SOL-0510-12:00:00 SOL-0510-11:03:40 SOL-0520-12:00:00 SOL-0520-11:09:44 SOL-0530-12:00:00 SOL-0530-11:16:19 SOL-0540-12:00:00 SOL-0540-11:23:16 SOL-0550-12:00:00 SOL-0550-11:30:22 SOL-0560-12:00:00 SOL-0560-11:37:24 SOL-0570-12:00:00 SOL-0570-11:44:08 SOL-0580-12:00:00 SOL-0580-11:50:24 SOL-0590-12:00:00 SOL-0590-11:56:01 SOL-0600-12:00:00 SOL-0600-12:00:52 SOL-0610-12:00:00 SOL-0610-12:04:52 SOL-0620-12:00:00 SOL-0620-12:07:58 SOL-0630-12:00:00 SOL-0630-12:10:11 SOL-0640-12:00:00 SOL-0640-12:11:32 SOL-0650-12:00:00 SOL-0650-12:12:04 SOL-0660-12:00:00 SOL-0660-12:11:51 SOL-0670-12:00:00 SOL-0670-12:10:57 SOL-0680-12:00:00 SOL-0680-12:09:27 SOL-0690-12:00:00 SOL-0690-12:07:26 SOL-0700-12:00:00 SOL-0700-12:04:58 SOL-0710-12:00:00 SOL-0710-12:02:08 SOL-0720-12:00:00 SOL-0720-11:59:00 SOL-0730-12:00:00 SOL-0730-11:55:38 SOL-0740-12:00:00 SOL-0740-11:52:07 SOL-0750-12:00:00 SOL-0750-11:48:29 SOL-0760-12:00:00 SOL-0760-11:44:48 SOL-0770-12:00:00 SOL-0770-11:41:07 SOL-0780-12:00:00 SOL-0780-11:37:29 SOL-0790-12:00:00 SOL-0790-11:33:57 SOL-0800-12:00:00 SOL-0800-11:30:32 SOL-0810-12:00:00 SOL-0810-11:27:15 SOL-0820-12:00:00 SOL-0820-11:24:09 SOL-0830-12:00:00 SOL-0830-11:21:15 SOL-0840-12:00:00 SOL-0840-11:18:33 SOL-0850-12:00:00 SOL-0850-11:16:04 SOL-0860-12:00:00 SOL-0860-11:13:47 SOL-0870-12:00:00 SOL-0870-11:11:43 SOL-0880-12:00:00 SOL-0880-11:09:50 SOL-0890-12:00:00 SOL-0890-11:08:06 SOL-0900-12:00:00 SOL-0900-11:06:31 SOL-0910-12:00:00 SOL-0910-11:05:03 SOL-0920-12:00:00 SOL-0920-11:03:40 SOL-0930-12:00:00 SOL-0930-11:02:19 SOL-0940-12:00:00 SOL-0940-11:01:00 SOL-0950-12:00:00 SOL-0950-10:59:41 SOL-0960-12:00:00 SOL-0960-10:58:20 SOL-0970-12:00:00 SOL-0970-10:56:57 SOL-0980-12:00:00 SOL-0980-10:55:30 SOL-0990-12:00:00 SOL-0990-10:53:59 SOL-1000-12:00:00 SOL-1000-10:52:26 SOL-1010-12:00:00 SOL-1010-10:50:50 SOL-1020-12:00:00 SOL-1020-10:49:14 SOL-1030-12:00:00 SOL-1030-10:47:38 SOL-1040-12:00:00 SOL-1040-10:46:06 SOL-1050-12:00:00 SOL-1050-10:44:40 SOL-1060-12:00:00 SOL-1060-10:43:23 SOL-1070-12:00:00 SOL-1070-10:42:19 SOL-1080-12:00:00 SOL-1080-10:41:33 SOL-1090-12:00:00 SOL-1090-10:41:07 SOL-1100-12:00:00 SOL-1100-10:41:08 SOL-1110-12:00:00 SOL-1110-10:41:39 SOL-1120-12:00:00 SOL-1120-10:42:46 SOL-1130-12:00:00 SOL-1130-10:44:31 SOL-1140-12:00:00 SOL-1140-10:47:00 SOL-1150-12:00:00 SOL-1150-10:50:14 SOL-1160-12:00:00 SOL-1160-10:54:15 SOL-1170-12:00:00 SOL-1170-10:59:02 SOL-1180-12:00:00 SOL-1180-11:04:33 SOL-1190-12:00:00 SOL-1190-11:10:41 SOL-1200-12:00:00 SOL-1200-11:17:20 SOL-1210-12:00:00 SOL-1210-11:24:18 SOL-1220-12:00:00 SOL-1220-11:31:24 SOL-1230-12:00:00 SOL-1230-11:38:23 SOL-1240-12:00:00 SOL-1240-11:45:04 SOL-1250-12:00:00 SOL-1250-11:51:15 SOL-1260-12:00:00 SOL-1260-11:56:45 SOL-1270-12:00:00 SOL-1270-12:01:29 SOL-1280-12:00:00 SOL-1280-12:05:21 SOL-1290-12:00:00 SOL-1290-12:08:19 SOL-1300-12:00:00 SOL-1300-12:10:24 SOL-1310-12:00:00 SOL-1310-12:11:38 SOL-1320-12:00:00 SOL-1320-12:12:03 SOL-1330-12:00:00 SOL-1330-12:11:44 SOL-1340-12:00:00 SOL-1340-12:10:44 SOL-1350-12:00:00 SOL-1350-12:09:10 SOL-1360-12:00:00 SOL-1360-12:07:04 SOL-1370-12:00:00 SOL-1370-12:04:33 SOL-1380-12:00:00 SOL-1380-12:01:40 SOL-1390-12:00:00 SOL-1390-11:58:30 SOL-1400-12:00:00 SOL-1400-11:55:07 SOL-1410-12:00:00 SOL-1410-11:51:34 SOL-1420-12:00:00 SOL-1420-11:47:56 SOL-1430-12:00:00 SOL-1430-11:44:15 SOL-1440-12:00:00 SOL-1440-11:40:34 SOL-1450-12:00:00 SOL-1450-11:36:58 SOL-1460-12:00:00 SOL-1460-11:33:26 SOL-1470-12:00:00 SOL-1470-11:30:02 SOL-1480-12:00:00 SOL-1480-11:26:47 SOL-1490-12:00:00 SOL-1490-11:23:43 SOL-1500-12:00:00 SOL-1500-11:20:51 SOL-1510-12:00:00 SOL-1510-11:18:11 SOL-1520-12:00:00 SOL-1520-11:15:44 SOL-1530-12:00:00 SOL-1530-11:13:29 SOL-1540-12:00:00 SOL-1540-11:11:26 SOL-1550-12:00:00 SOL-1550-11:09:34 SOL-1560-12:00:00 SOL-1560-11:07:52 SOL-1570-12:00:00 SOL-1570-11:06:18 SOL-1580-12:00:00 SOL-1580-11:04:51 SOL-1590-12:00:00 SOL-1590-11:03:28 SOL-1600-12:00:00 SOL-1600-11:02:09 SOL-1610-12:00:00 SOL-1610-11:00:50 SOL-1620-12:00:00 SOL-1620-10:59:30 SOL-1630-12:00:00 SOL-1630-10:58:09 SOL-1640-12:00:00 SOL-1640-10:56:45 SOL-1650-12:00:00 SOL-1650-10:55:17 SOL-1660-12:00:00 SOL-1660-10:53:46 SOL-1670-12:00:00 SOL-1670-10:52:12 SOL-1680-12:00:00 SOL-1680-10:50:36 SOL-1690-12:00:00 SOL-1690-10:49:00 SOL-1700-12:00:00 SOL-1700-10:47:24 SOL-1710-12:00:00 SOL-1710-10:45:53 SOL-1720-12:00:00 SOL-1720-10:44:28 SOL-1730-12:00:00 SOL-1730-10:43:13 SOL-1740-12:00:00 SOL-1740-10:42:11 SOL-1750-12:00:00 SOL-1750-10:41:27 SOL-1760-12:00:00 SOL-1760-10:41:05 SOL-1770-12:00:00 SOL-1770-10:41:10 SOL-1780-12:00:00 SOL-1780-10:41:46 SOL-1790-12:00:00 SOL-1790-10:42:59 SOL-1800-12:00:00 SOL-1800-10:44:50 SOL-1810-12:00:00 SOL-1810-10:47:25 SOL-1820-12:00:00 SOL-1820-10:50:46 SOL-1830-12:00:00 SOL-1830-10:54:54 SOL-1840-12:00:00 SOL-1840-10:59:48 SOL-1850-12:00:00 SOL-1850-11:05:25 SOL-1860-12:00:00 SOL-1860-11:11:39 SOL-1870-12:00:00 SOL-1870-11:18:22 SOL-1880-12:00:00 SOL-1880-11:25:22 SOL-1890-12:00:00 SOL-1890-11:32:28 SOL-1900-12:00:00 SOL-1900-11:39:26 SOL-1910-12:00:00 SOL-1910-11:46:03 SOL-1920-12:00:00 SOL-1920-11:52:08 SOL-1930-12:00:00 SOL-1930-11:57:33 SOL-1940-12:00:00 SOL-1940-12:02:09 SOL-1950-12:00:00 SOL-1950-12:05:53 SOL-1960-12:00:00 SOL-1960-12:08:44 SOL-1970-12:00:00 SOL-1970-12:10:41 SOL-1980-12:00:00 SOL-1980-12:11:48 SOL-1990-12:00:00 SOL-1990-12:12:06 SOL-2000-12:00:00 SOL-2000-12:11:41 SOL-2010-12:00:00 SOL-2010-12:10:36 SOL-2020-12:00:00 SOL-2020-12:08:56 SOL-2030-12:00:00 SOL-2030-12:06:47 SOL-2040-12:00:00 SOL-2040-12:04:12 SOL-2050-12:00:00 SOL-2050-12:01:16 SOL-2060-12:00:00 SOL-2060-11:58:04 SOL-2070-12:00:00 SOL-2070-11:54:39 SOL-2080-12:00:00 SOL-2080-11:51:05 SOL-2090-12:00:00 SOL-2090-11:47:26 SOL-2100-12:00:00 SOL-2100-11:43:45 SOL-2110-12:00:00 SOL-2110-11:40:04 SOL-2120-12:00:00 SOL-2120-11:36:28 SOL-2130-12:00:00 SOL-2130-11:32:57 SOL-2140-12:00:00 SOL-2140-11:29:34 SOL-2150-12:00:00 SOL-2150-11:26:21 SOL-2160-12:00:00 SOL-2160-11:23:18 SOL-2170-12:00:00 SOL-2170-11:20:28 SOL-2180-12:00:00 SOL-2180-11:17:50 SOL-2190-12:00:00 SOL-2190-11:15:24 SOL-2200-12:00:00 SOL-2200-11:13:11 SOL-2210-12:00:00 SOL-2210-11:11:10 SOL-2220-12:00:00 SOL-2220-11:09:20 SOL-2230-12:00:00 SOL-2230-11:07:39 SOL-2240-12:00:00 SOL-2240-11:06:07 SOL-2250-12:00:00 SOL-2250-11:04:40 SOL-2260-12:00:00 SOL-2260-11:03:18 SOL-2270-12:00:00 SOL-2270-11:01:58 SOL-2280-12:00:00 SOL-2280-11:00:40 SOL-2290-12:00:00 SOL-2290-10:59:20 SOL-2300-12:00:00 SOL-2300-10:57:59 SOL-2310-12:00:00 SOL-2310-10:56:34 SOL-2320-12:00:00 SOL-2320-10:55:06 SOL-2330-12:00:00 SOL-2330-10:53:35 SOL-2340-12:00:00 SOL-2340-10:52:00 SOL-2350-12:00:00 SOL-2350-10:50:24 SOL-2360-12:00:00 SOL-2360-10:48:48 SOL-2370-12:00:00 SOL-2370-10:47:13 SOL-2380-12:00:00 SOL-2380-10:45:42 SOL-2390-12:00:00 SOL-2390-10:44:17 SOL-2400-12:00:00 SOL-2400-10:43:04 SOL-2410-12:00:00 SOL-2410-10:42:04 SOL-2420-12:00:00 SOL-2420-10:41:23 SOL-2430-12:00:00 SOL-2430-10:41:04 SOL-2440-12:00:00 SOL-2440-10:41:13 SOL-2450-12:00:00 SOL-2450-10:41:54 SOL-2460-12:00:00 SOL-2460-10:43:11 SOL-2470-12:00:00 SOL-2470-10:45:08 SOL-2480-12:00:00 SOL-2480-10:47:49 SOL-2490-12:00:00 SOL-2490-10:51:16 SOL-2500-12:00:00 SOL-2500-10:55:30 SOL-2510-12:00:00 SOL-2510-11:00:30 SOL-2520-12:00:00 SOL-2520-11:06:12 SOL-2530-12:00:00 SOL-2530-11:12:30 SOL-2540-12:00:00 SOL-2540-11:19:16 SOL-2550-12:00:00 SOL-2550-11:26:18 SOL-2560-12:00:00 SOL-2560-11:33:23 SOL-2570-12:00:00 SOL-2570-11:40:19 SOL-2580-12:00:00 SOL-2580-11:46:53 SOL-2590-12:00:00 SOL-2590-11:52:54 SOL-2600-12:00:00 SOL-2600-11:58:12 SOL-2610-12:00:00 SOL-2610-12:02:41 SOL-2620-12:00:00 SOL-2620-12:06:19 SOL-2630-12:00:00 SOL-2630-12:09:02 SOL-2640-12:00:00 SOL-2640-12:10:53 SOL-2650-12:00:00 SOL-2650-12:11:52 SOL-2660-12:00:00 SOL-2660-12:12:05 SOL-2670-12:00:00 SOL-2670-12:11:34 SOL-2680-12:00:00 SOL-2680-12:10:24 SOL-2690-12:00:00 SOL-2690-12:08:40 SOL-2700-12:00:00 SOL-2700-12:06:27 SOL-2710-12:00:00 SOL-2710-12:03:49 SOL-2720-12:00:00 SOL-2720-12:00:51 SOL-2730-12:00:00 SOL-2730-11:57:36 SOL-2740-12:00:00 SOL-2740-11:54:10 SOL-2750-12:00:00 SOL-2750-11:50:35 SOL-2760-12:00:00 SOL-2760-11:46:56 SOL-2770-12:00:00 SOL-2770-11:43:14 SOL-2780-12:00:00 SOL-2780-11:39:35 SOL-2790-12:00:00 SOL-2790-11:35:59 SOL-2800-12:00:00 SOL-2800-11:32:29 SOL-2810-12:00:00 SOL-2810-11:29:07 SOL-2820-12:00:00 SOL-2820-11:25:55 SOL-2830-12:00:00 SOL-2830-11:22:54 SOL-2840-12:00:00 SOL-2840-11:20:05 SOL-2850-12:00:00 SOL-2850-11:17:28 SOL-2860-12:00:00 SOL-2860-11:15:04 SOL-2870-12:00:00 SOL-2870-11:12:53 SOL-2880-12:00:00 SOL-2880-11:10:54 SOL-2890-12:00:00 SOL-2890-11:09:05 SOL-2900-12:00:00 SOL-2900-11:07:25 SOL-2910-12:00:00 SOL-2910-11:05:53 SOL-2920-12:00:00 SOL-2920-11:04:28 SOL-2930-12:00:00 SOL-2930-11:03:06 SOL-2940-12:00:00 SOL-2940-11:01:47 SOL-2950-12:00:00 SOL-2950-11:00:28 SOL-2960-12:00:00 SOL-2960-10:59:08 SOL-2970-12:00:00 SOL-2970-10:57:46 SOL-2980-12:00:00 SOL-2980-10:56:22 SOL-2990-12:00:00 SOL-2990-10:54:53 SOL-3000-12:00:00 SOL-3000-10:53:22 MER-2 TLST vs. HLST table: True LST Hybrid LST ----------------- ----------------- SOL-0001-12:00:00 SOL-0001-12:09:17 SOL-0010-12:00:00 SOL-0010-12:09:10 SOL-0020-12:00:00 SOL-0020-12:08:23 SOL-0030-12:00:00 SOL-0030-12:06:59 SOL-0040-12:00:00 SOL-0040-12:05:03 SOL-0050-12:00:00 SOL-0050-12:02:40 SOL-0060-12:00:00 SOL-0060-11:59:54 SOL-0070-12:00:00 SOL-0070-11:56:48 SOL-0080-12:00:00 SOL-0080-11:53:29 SOL-0090-12:00:00 SOL-0090-11:49:58 SOL-0100-12:00:00 SOL-0100-11:46:21 SOL-0110-12:00:00 SOL-0110-11:42:40 SOL-0120-12:00:00 SOL-0120-11:38:59 SOL-0130-12:00:00 SOL-0130-11:35:20 SOL-0140-12:00:00 SOL-0140-11:31:46 SOL-0150-12:00:00 SOL-0150-11:28:18 SOL-0160-12:00:00 SOL-0160-11:25:00 SOL-0170-12:00:00 SOL-0170-11:21:52 SOL-0180-12:00:00 SOL-0180-11:18:55 SOL-0190-12:00:00 SOL-0190-11:16:11 SOL-0200-12:00:00 SOL-0200-11:13:39 SOL-0210-12:00:00 SOL-0210-11:11:20 SOL-0220-12:00:00 SOL-0220-11:09:13 SOL-0230-12:00:00 SOL-0230-11:07:17 SOL-0240-12:00:00 SOL-0240-11:05:32 SOL-0250-12:00:00 SOL-0250-11:03:56 SOL-0260-12:00:00 SOL-0260-11:02:26 SOL-0270-12:00:00 SOL-0270-11:01:02 SOL-0280-12:00:00 SOL-0280-10:59:41 SOL-0290-12:00:00 SOL-0290-10:58:22 SOL-0300-12:00:00 SOL-0300-10:57:03 SOL-0310-12:00:00 SOL-0310-10:55:42 SOL-0320-12:00:00 SOL-0320-10:54:19 SOL-0330-12:00:00 SOL-0330-10:52:53 SOL-0340-12:00:00 SOL-0340-10:51:23 SOL-0350-12:00:00 SOL-0350-10:49:50 SOL-0360-12:00:00 SOL-0360-10:48:15 SOL-0370-12:00:00 SOL-0370-10:46:38 SOL-0380-12:00:00 SOL-0380-10:45:02 SOL-0390-12:00:00 SOL-0390-10:43:29 SOL-0400-12:00:00 SOL-0400-10:42:01 SOL-0410-12:00:00 SOL-0410-10:40:42 SOL-0420-12:00:00 SOL-0420-10:39:35 SOL-0430-12:00:00 SOL-0430-10:38:45 SOL-0440-12:00:00 SOL-0440-10:38:15 SOL-0450-12:00:00 SOL-0450-10:38:10 SOL-0460-12:00:00 SOL-0460-10:38:35 SOL-0470-12:00:00 SOL-0470-10:39:34 SOL-0480-12:00:00 SOL-0480-10:41:11 SOL-0490-12:00:00 SOL-0490-10:43:31 SOL-0500-12:00:00 SOL-0500-10:46:37 SOL-0510-12:00:00 SOL-0510-10:50:29 SOL-0520-12:00:00 SOL-0520-10:55:07 SOL-0530-12:00:00 SOL-0530-11:00:30 SOL-0540-12:00:00 SOL-0540-11:06:33 SOL-0550-12:00:00 SOL-0550-11:13:07 SOL-0560-12:00:00 SOL-0560-11:20:03 SOL-0570-12:00:00 SOL-0570-11:27:08 SOL-0580-12:00:00 SOL-0580-11:34:11 SOL-0590-12:00:00 SOL-0590-11:40:57 SOL-0600-12:00:00 SOL-0600-11:47:14 SOL-0610-12:00:00 SOL-0610-11:52:54 SOL-0620-12:00:00 SOL-0620-11:57:47 SOL-0630-12:00:00 SOL-0630-12:01:49 SOL-0640-12:00:00 SOL-0640-12:04:58 SOL-0650-12:00:00 SOL-0650-12:07:14 SOL-0660-12:00:00 SOL-0660-12:08:38 SOL-0670-12:00:00 SOL-0670-12:09:13 SOL-0680-12:00:00 SOL-0680-12:09:02 SOL-0690-12:00:00 SOL-0690-12:08:10 SOL-0700-12:00:00 SOL-0700-12:06:42 SOL-0710-12:00:00 SOL-0710-12:04:42 SOL-0720-12:00:00 SOL-0720-12:02:15 SOL-0730-12:00:00 SOL-0730-11:59:26 SOL-0740-12:00:00 SOL-0740-11:56:19 SOL-0750-12:00:00 SOL-0750-11:52:58 SOL-0760-12:00:00 SOL-0760-11:49:27 SOL-0770-12:00:00 SOL-0770-11:45:49 SOL-0780-12:00:00 SOL-0780-11:42:08 SOL-0790-12:00:00 SOL-0790-11:38:27 SOL-0800-12:00:00 SOL-0800-11:34:49 SOL-0810-12:00:00 SOL-0810-11:31:16 SOL-0820-12:00:00 SOL-0820-11:27:50 SOL-0830-12:00:00 SOL-0830-11:24:33 SOL-0840-12:00:00 SOL-0840-11:21:27 SOL-0850-12:00:00 SOL-0850-11:18:32 SOL-0860-12:00:00 SOL-0860-11:15:49 SOL-0870-12:00:00 SOL-0870-11:13:20 SOL-0880-12:00:00 SOL-0880-11:11:02 SOL-0890-12:00:00 SOL-0890-11:08:57 SOL-0900-12:00:00 SOL-0900-11:07:03 SOL-0910-12:00:00 SOL-0910-11:05:20 SOL-0920-12:00:00 SOL-0920-11:03:44 SOL-0930-12:00:00 SOL-0930-11:02:16 SOL-0940-12:00:00 SOL-0940-11:00:52 SOL-0950-12:00:00 SOL-0950-10:59:32 SOL-0960-12:00:00 SOL-0960-10:58:13 SOL-0970-12:00:00 SOL-0970-10:56:54 SOL-0980-12:00:00 SOL-0980-10:55:33 SOL-0990-12:00:00 SOL-0990-10:54:09 SOL-1000-12:00:00 SOL-1000-10:52:43 SOL-1010-12:00:00 SOL-1010-10:51:12 SOL-1020-12:00:00 SOL-1020-10:49:39 SOL-1030-12:00:00 SOL-1030-10:48:04 SOL-1040-12:00:00 SOL-1040-10:46:27 SOL-1050-12:00:00 SOL-1050-10:44:51 SOL-1060-12:00:00 SOL-1060-10:43:19 SOL-1070-12:00:00 SOL-1070-10:41:52 SOL-1080-12:00:00 SOL-1080-10:40:35 SOL-1090-12:00:00 SOL-1090-10:39:31 SOL-1100-12:00:00 SOL-1100-10:38:43 SOL-1110-12:00:00 SOL-1110-10:38:17 SOL-1120-12:00:00 SOL-1120-10:38:16 SOL-1130-12:00:00 SOL-1130-10:38:45 SOL-1140-12:00:00 SOL-1140-10:39:50 SOL-1150-12:00:00 SOL-1150-10:41:33 SOL-1160-12:00:00 SOL-1160-10:43:59 SOL-1170-12:00:00 SOL-1170-10:47:11 SOL-1180-12:00:00 SOL-1180-10:51:09 SOL-1190-12:00:00 SOL-1190-10:55:54 SOL-1200-12:00:00 SOL-1200-11:01:23 SOL-1210-12:00:00 SOL-1210-11:07:30 SOL-1220-12:00:00 SOL-1220-11:14:07 SOL-1230-12:00:00 SOL-1230-11:21:05 SOL-1240-12:00:00 SOL-1240-11:28:10 SOL-1250-12:00:00 SOL-1250-11:35:11 SOL-1260-12:00:00 SOL-1260-11:41:53 SOL-1270-12:00:00 SOL-1270-11:48:05 SOL-1280-12:00:00 SOL-1280-11:53:39 SOL-1290-12:00:00 SOL-1290-11:58:25 SOL-1300-12:00:00 SOL-1300-12:02:19 SOL-1310-12:00:00 SOL-1310-12:05:20 SOL-1320-12:00:00 SOL-1320-12:07:28 SOL-1330-12:00:00 SOL-1330-12:08:44 SOL-1340-12:00:00 SOL-1340-12:09:12 SOL-1350-12:00:00 SOL-1350-12:08:55 SOL-1360-12:00:00 SOL-1360-12:07:57 SOL-1370-12:00:00 SOL-1370-12:06:24 SOL-1380-12:00:00 SOL-1380-12:04:20 SOL-1390-12:00:00 SOL-1390-12:01:50 SOL-1400-12:00:00 SOL-1400-11:58:58 SOL-1410-12:00:00 SOL-1410-11:55:49 SOL-1420-12:00:00 SOL-1420-11:52:26 SOL-1430-12:00:00 SOL-1430-11:48:54 SOL-1440-12:00:00 SOL-1440-11:45:16 SOL-1450-12:00:00 SOL-1450-11:41:35 SOL-1460-12:00:00 SOL-1460-11:37:55 SOL-1470-12:00:00 SOL-1470-11:34:17 SOL-1480-12:00:00 SOL-1480-11:30:45 SOL-1490-12:00:00 SOL-1490-11:27:20 SOL-1500-12:00:00 SOL-1500-11:24:05 SOL-1510-12:00:00 SOL-1510-11:21:00 SOL-1520-12:00:00 SOL-1520-11:18:07 SOL-1530-12:00:00 SOL-1530-11:15:27 SOL-1540-12:00:00 SOL-1540-11:12:59 SOL-1550-12:00:00 SOL-1550-11:10:44 SOL-1560-12:00:00 SOL-1560-11:08:40 SOL-1570-12:00:00 SOL-1570-11:06:48 SOL-1580-12:00:00 SOL-1580-11:05:06 SOL-1590-12:00:00 SOL-1590-11:03:31 SOL-1600-12:00:00 SOL-1600-11:02:04 SOL-1610-12:00:00 SOL-1610-11:00:41 SOL-1620-12:00:00 SOL-1620-10:59:21 SOL-1630-12:00:00 SOL-1630-10:58:02 SOL-1640-12:00:00 SOL-1640-10:56:43 SOL-1650-12:00:00 SOL-1650-10:55:21 SOL-1660-12:00:00 SOL-1660-10:53:57 SOL-1670-12:00:00 SOL-1670-10:52:30 SOL-1680-12:00:00 SOL-1680-10:50:59 SOL-1690-12:00:00 SOL-1690-10:49:26 SOL-1700-12:00:00 SOL-1700-10:47:50 SOL-1710-12:00:00 SOL-1710-10:46:13 SOL-1720-12:00:00 SOL-1720-10:44:38 SOL-1730-12:00:00 SOL-1730-10:43:06 SOL-1740-12:00:00 SOL-1740-10:41:40 SOL-1750-12:00:00 SOL-1750-10:40:25 SOL-1760-12:00:00 SOL-1760-10:39:22 SOL-1770-12:00:00 SOL-1770-10:38:38 SOL-1780-12:00:00 SOL-1780-10:38:14 SOL-1790-12:00:00 SOL-1790-10:38:18 SOL-1800-12:00:00 SOL-1800-10:38:52 SOL-1810-12:00:00 SOL-1810-10:40:02 SOL-1820-12:00:00 SOL-1820-10:41:51 SOL-1830-12:00:00 SOL-1830-10:44:24 SOL-1840-12:00:00 SOL-1840-10:47:43 SOL-1850-12:00:00 SOL-1850-10:51:48 SOL-1860-12:00:00 SOL-1860-10:56:40 SOL-1870-12:00:00 SOL-1870-11:02:15 SOL-1880-12:00:00 SOL-1880-11:08:27 SOL-1890-12:00:00 SOL-1890-11:15:09 SOL-1900-12:00:00 SOL-1900-11:22:09 SOL-1910-12:00:00 SOL-1910-11:29:15 SOL-1920-12:00:00 SOL-1920-11:36:14 SOL-1930-12:00:00 SOL-1930-11:42:53 SOL-1940-12:00:00 SOL-1940-11:49:00 SOL-1950-12:00:00 SOL-1950-11:54:26 SOL-1960-12:00:00 SOL-1960-11:59:05 SOL-1970-12:00:00 SOL-1970-12:02:52 SOL-1980-12:00:00 SOL-1980-12:05:45 SOL-1990-12:00:00 SOL-1990-12:07:46 SOL-2000-12:00:00 SOL-2000-12:08:54 SOL-2010-12:00:00 SOL-2010-12:09:15 SOL-2020-12:00:00 SOL-2020-12:08:52 SOL-2030-12:00:00 SOL-2030-12:07:49 SOL-2040-12:00:00 SOL-2040-12:06:11 SOL-2050-12:00:00 SOL-2050-12:04:03 SOL-2060-12:00:00 SOL-2060-12:01:29 SOL-2070-12:00:00 SOL-2070-11:58:34 SOL-2080-12:00:00 SOL-2080-11:55:23 SOL-2090-12:00:00 SOL-2090-11:51:58 SOL-2100-12:00:00 SOL-2100-11:48:25 SOL-2110-12:00:00 SOL-2110-11:44:46 SOL-2120-12:00:00 SOL-2120-11:41:05 SOL-2130-12:00:00 SOL-2130-11:37:24 SOL-2140-12:00:00 SOL-2140-11:33:47 SOL-2150-12:00:00 SOL-2150-11:30:16 SOL-2160-12:00:00 SOL-2160-11:26:53 SOL-2170-12:00:00 SOL-2170-11:23:39 SOL-2180-12:00:00 SOL-2180-11:20:35 SOL-2190-12:00:00 SOL-2190-11:17:44 SOL-2200-12:00:00 SOL-2200-11:15:05 SOL-2210-12:00:00 SOL-2210-11:12:39 SOL-2220-12:00:00 SOL-2220-11:10:26 SOL-2230-12:00:00 SOL-2230-11:08:24 SOL-2240-12:00:00 SOL-2240-11:06:33 SOL-2250-12:00:00 SOL-2250-11:04:52 SOL-2260-12:00:00 SOL-2260-11:03:19 SOL-2270-12:00:00 SOL-2270-11:01:53 SOL-2280-12:00:00 SOL-2280-11:00:30 SOL-2290-12:00:00 SOL-2290-10:59:11 SOL-2300-12:00:00 SOL-2300-10:57:52 SOL-2310-12:00:00 SOL-2310-10:56:33 SOL-2320-12:00:00 SOL-2320-10:55:11 SOL-2330-12:00:00 SOL-2330-10:53:47 SOL-2340-12:00:00 SOL-2340-10:52:19 SOL-2350-12:00:00 SOL-2350-10:50:48 SOL-2360-12:00:00 SOL-2360-10:49:14 SOL-2370-12:00:00 SOL-2370-10:47:38 SOL-2380-12:00:00 SOL-2380-10:46:01 SOL-2390-12:00:00 SOL-2390-10:44:26 SOL-2400-12:00:00 SOL-2400-10:42:54 SOL-2410-12:00:00 SOL-2410-10:41:30 SOL-2420-12:00:00 SOL-2420-10:40:16 SOL-2430-12:00:00 SOL-2430-10:39:15 SOL-2440-12:00:00 SOL-2440-10:38:33 SOL-2450-12:00:00 SOL-2450-10:38:13 SOL-2460-12:00:00 SOL-2460-10:38:20 SOL-2470-12:00:00 SOL-2470-10:38:59 SOL-2480-12:00:00 SOL-2480-10:40:14 SOL-2490-12:00:00 SOL-2490-10:42:08 SOL-2500-12:00:00 SOL-2500-10:44:47 SOL-2510-12:00:00 SOL-2510-10:48:13 SOL-2520-12:00:00 SOL-2520-10:52:25 SOL-2530-12:00:00 SOL-2530-10:57:22 SOL-2540-12:00:00 SOL-2540-11:03:03 SOL-2550-12:00:00 SOL-2550-11:09:19 SOL-2560-12:00:00 SOL-2560-11:16:04 SOL-2570-12:00:00 SOL-2570-11:23:05 SOL-2580-12:00:00 SOL-2580-11:30:11 SOL-2590-12:00:00 SOL-2590-11:37:08 SOL-2600-12:00:00 SOL-2600-11:43:43 SOL-2610-12:00:00 SOL-2610-11:49:45 SOL-2620-12:00:00 SOL-2620-11:55:06 SOL-2630-12:00:00 SOL-2630-11:59:38 SOL-2640-12:00:00 SOL-2640-12:03:18 SOL-2650-12:00:00 SOL-2650-12:06:04 SOL-2660-12:00:00 SOL-2660-12:07:57 SOL-2670-12:00:00 SOL-2670-12:08:59 SOL-2680-12:00:00 SOL-2680-12:09:14 SOL-2690-12:00:00 SOL-2690-12:08:45 SOL-2700-12:00:00 SOL-2700-12:07:37 SOL-2710-12:00:00 SOL-2710-12:05:55 SOL-2720-12:00:00 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SOL-3000-12:00:00 SOL-3000-10:53:34 Fractional Part of the On-board Clock Strings -------------------------------------------------------- In MER science product labels and accompanying documentation, and in supporting data products, the on-board clock (SCLK) times are represented by a string in the "SSSSSSSSS.FFF" format. In this string "SSSSSSSSS" represents integer SCLK seconds while "FFF" represents fractional SCLK seconds. Unfortunately the meaning of "FFF" varies across different data sets. In some cases it means a true decimal fraction (i.e. milliseconds) while in other cases it stands for a count of 1/256th of a second (which stems from the fact that the fractional part was represented by a single byte in the original telemetry stream.) When comparing SCLK times or converting them to other time systems, it is important to know which of the two representations the SCLK string follows. Normally the documentation accompanying a particular data set -- such as the product SIS, or other label content specification document -- defines which type of SCLK fractional part was used in that data set. The SPICE system SCLK conversion routines expect the fractional part to be the count of 1/256th of a second. To convert an SCLK tag with milliseconds to that format one could use the following simple approach: starting with an SCLK with milliseconds (for example "129882123.725"), multiply the fractional part by 256 (0.725 * 256 = 185.6), round to the nearest integer (186), and replace the milliseconds portion of the string with it ("129882123.725" becomes "129882123.186".)