From AC Mon May 6 13:22:38 1996 From: AC (AC) Date: Mon, 6 May 1996 13:22:38 PDT Subject: [IGSMAIL-1305] Wk 0843-6 IGS Final Orbits Message-ID: ****************************************************************************** IGS Electronic Mail Mon May 6 13:22:38 PDT 1996 Message Number 1305 ****************************************************************************** Author: AC Coordinator Subject: Wk 0843-6 IGS Final Orbits ******************************************************************************* IGS Final orbits/clocks completed and put onto CDDIS (Weeks 843 - 846) (Mar 03/96 Mar 30, 1996) ******************************************************************************* The IGS Rapid Orbits for this period were recomputed using up to date orbits and the final EOP values of Bulletin B, published by IERS. ( Daily values, page 2 of Bull. B ) The EOP were corrected for the difference between the IERS pole series and ITRF as published in the IERS 1993 Annual Report (p. II-19, Table II-3), so both the IGS orbits and the associated ERP files are consistent with ITRF93 (current epoch). We have downloaded all the submitted ephemeris and ERP files from CDDIS before the final orbit/clock combination to ensure that the sets are complete and up to date. In the final combination we have largely followed the actions taken during the Rapid orbit generation and since there were very few orbit resubmissions, both the IGS Rapid and Final orbits are virtually the same except for the orientation difference (IGS mean pole and Bull.B). Orbit evaluation are also nearly the same, since we used centre specific ERP in the long arc evaluations. For more information see the corresponding summary files on CDDIS. The clock solution alignment and centre clock weight assignment are based on non-SA broadcast satellite corrections only (PRN12, 15, 28). This should result in an objective clock weighting, provided that the non-SA satellites are representative of centre clock solution quality. Starting with the GPS week 756 the new IGS erp format (see IGSMAIL# 662) is used by all Analysis Centres and for the IGS erp files. ERP rates, whenever given, are also utilized in both orbit combination and the long arc evaluation. PRODUCTS GENERATED: The resulting final IGS ephemeris and clocks are in daily files in the SP3 format. The sat. orb. accuracy codes displayed in the headers are based on weighted RMS for each satellite. Note that each file contains all the submitted satellites. If a satellite or centre had to be excluded from the combination it is noted in the summary file along with the reason for doing so. The IGS FINAL ORBIT files generated and uploaded into CDDIS @ NASA/GSFC are: IGS08430-6.SP3 IGS GPS orbit/clock files for days 0-6, week 0843 IGS08440-6.SP3 IGS GPS orbit/clock files for days 0-6, week 0844 IGS08450-6.SP3 IGS GPS orbit/clock files for days 0-6, week 0845 IGS08460-6.SP3 IGS GPS orbit/clock files for days 0-6, week 0846 IGS08437.ERP EOP associated with the above orbits (Bull. B aligned to ITRF) IGS08447.ERP EOP associated with the above orbits (Bull. B aligned to ITRF) IGS08457.ERP EOP associated with the above orbits (Bull. B aligned to ITRF) IGS08467.ERP EOP associated with the above orbits (Bull. B aligned to ITRF) IGS08437.SUM Complete summary/statistics report IGS08447.SUM Complete summary/statistics report IGS08457.SUM Complete summary/statistics report IGS08467.SUM Complete summary/statistics report The old Rapid Orbit files have been renamed (on CDDIS) to: (Note this is temporary, based on discussions with ACs and GB and may be changed) IGR08430-6.SP3 Rapid service orbits/clocks for days 0-6, week 0843 IGR08440-6.SP3 Rapid service orbits/clocks for days 0-6, week 0844 IGR08450-6.SP3 Rapid service orbits/clocks for days 0-6, week 0845 IGR08460-6.SP3 Rapid service orbits/clocks for days 0-6, week 0846 IGR08437.ERP IGS Mean EOP associated with the above orbits IGR08447.ERP IGS Mean EOP associated with the above orbits IGR08457.ERP IGS Mean EOP associated with the above orbits IGR08467.ERP IGS Mean EOP associated with the above orbits IGR08437.SUM Rapid service complete summary/statistic report IGR08447.SUM Rapid service complete summary/statistic report IGR08457.SUM Rapid service complete summary/statistic report IGR08467.SUM Rapid service complete summary/statistic report ***************************************************************************** REMARKS/CORRECTIONS: ************* NOTE: *************************** Since Wk803 the IGS Rapid combinations are performed directly in the ITRF frame without any EOP alignments. The associated erp files (IGR0WWW7.erp) contain weighted averages of all submitted erp solutions given at 12h UT each day (using the orbit weights), augmented with the current IERS Bull.A UT1-UTC. Consequently, since Wk 803, the IGR erp contains 7 daily EOP values at 12h UT, unlike the Final orbit erp (and the Rapid orbit erp prior Wk 803) which contain 9 daily IERS EOP values at 0h UT to facilitate accurate interpolation at the beginning and the end of the week. *********************************************** The following table shows the average statistics of the Final orbit/clock combination for the current period (Wks 0843-0846). Start: 96 Mar 3 / wk843 End: 96 Mar 30 / wk846 STA DX DY DZ RX RY RZ SCL RMS WRMS LaRMS RMSc Days ---------------------------------------------------------------------------- cod 67 0.00 0.01 0.00 -0.41 0.08 -0.04 0.2 7 5 10 1.7 28 0.00 0.00 0.00 0.13 0.10 0.28 0.1 emr 28 0.01 0.00 0.00 0.17 -0.13 0.30 -0.2 11 11 14 0.8 28 0.01 0.01 0.01 0.13 0.19 0.23 0.1 esa 56 0.01 -0.01 -0.01 -0.17 0.12 0.01 0.2 11 10 14 5.7 28 0.01 0.02 0.01 0.27 0.19 0.19 0.1 gfz 47 -0.03 -0.05 -0.01 0.01 -0.01 -0.29 -0.2 74 80 16 0.7 28 0.01 0.01 0.01 0.11 0.13 0.19 0.2 jpl 37 0.01 0.02 0.00 -0.42 0.09 0.02 0.1 7 7 11 0.8 28 0.01 0.01 0.01 0.10 0.16 0.12 0.1 ngs 45 0.02 -0.05 0.01 0.00 0.62 -0.07 -0.2 16 17 18 8358.0 28 0.01 0.01 0.01 0.25 0.33 0.26 0.2 sio 111 -0.01 0.02 0.01 -0.15 -0.19 -0.03 0.0 72 38 15 0.0 28 0.00 0.01 0.01 0.12 0.13 0.30 0.1 Units: m - DX, DY, DZ mas - RX,RY,RZ ppb - SCL cm - RMS, WRMS, LaRMS (Long arc orbit RMS) ns - RMSc (sv clock) The following table shows the average statistics of the Final orbit/clock combination for the current year (Wks 0834-0846). Start: 95 Dec 31 / wk834 End: 96 Mar 30 / wk846 STA DX DY DZ RX RY RZ SCL RMS WRMS LaRMS RMSc Days ---------------------------------------------------------------------------- cod 65 0.00 0.02 0.00 -0.41 0.04 -0.07 0.1 7 6 10 2.0 91 0.01 0.01 0.01 0.20 0.18 0.23 0.1 emr 28 0.01 -0.02 -0.01 0.13 -0.10 0.36 -0.2 10 10 14 0.9 91 0.01 0.02 0.01 0.17 0.20 0.19 0.1 esa 52 0.00 -0.02 -0.01 -0.07 0.20 -0.11 0.1 14 12 15 3043.2 91 0.01 0.01 0.01 0.30 0.24 0.31 0.2 gfz 45 -0.03 -0.03 0.00 -0.03 -0.09 -0.26 -0.3 44 47 15 5.3 91 0.01 0.01 0.01 0.13 0.16 0.20 0.1 jpl 37 0.01 0.02 0.00 -0.40 0.06 0.05 0.1 7 7 10 0.9 91 0.01 0.01 0.01 0.12 0.18 0.12 0.1 ngs 44 0.01 -0.04 0.02 -0.07 0.51 -0.01 -0.2 293 205 17 9317.5 91 0.01 0.02 0.02 0.28 0.32 0.28 0.2 sio 110 -0.01 0.03 0.01 -0.21 -0.12 1.69 0.1 1021 950 12 0.0 91 0.01 0.06 0.01 0.30 0.29 16.17 0.2 Units: m - DX, DY, DZ mas - RX,RY,RZ ppb - SCL cm - RMS, WRMS, LaRMS (Long arc orbit RMS) ns - RMSc (sv clock) [Mailed From: Jan Kouba ]