LAGEOS 1	Duration	LAGEOS 2	Duration
L1-990702-31	99,07,02-07,31	L2-990702-31	99,07,02-07,31
L1-990801-15	99,08,01-08,15	L2-990801-15	99,08,01-08,15
L1-990816-30	99,08,16-08,30	L2-990816-30	99,08,16-08,30
L1-990831-14	99,08,31-09,14	L2-990831-14	99,08,31-09,14
L1-990915-02	99,09,15-10,02	L2-990915-02	99,09,15-10,02
L1-990930-14	99,09,30-10,14	L2-990930-14	99,09,30-10,14
L1-991012-26	99,10,12-10,26	L2-991012-26	99,10,12-10,26
L1-991027-12	99,10,27-11,12	L2-991027-12	99,10,27-11,12
L1-991113-30	99,11,13-11,30	L2-991113-30	99,11,13-11,30
L1-991201-15	99,12,01-12,15	L2-991201-15	99,12,01-12,15
L1-991213-21	99,12,13-12,21	L2-991213-21	99,12,13-12,21
L1-991220-31	99,12,20-12,31	L2-991220-28	99,12,20-12,28
L1-000101-12	00,01,01-01,12	L2-000101-12	00,01,01-01,12
L1-000113-27	00,01,13-01,27	L2-000113-27	00,01,13-01,27
L1-000125-14	00,01,25-02,14	L2-000125-14	00,01,25-02,14
L1-000212-26	00,02,12-02,26	L2-000212-26	00,02,12-02,26
L1-000224-15	00,02,24-03,15	L2-000224-15	00,02,24-03,25
L1-000310-30	00,03,10-03,30	L2-000310-30	00,03,10-03,30
L1-000331-14	00,03,31-04,14	L2-000331-14	00,03,31-04,14
L1-000412-26	00,04,12-04,26	L2-000412-26	00,04,12-04,26
L1-000424-02	00,04,24-05,02	L2-000424-02	00,04,24-05,02
L1-000430-08	00,04,30-05,08	L2-000430-08	00,04,30-05,08
L1-000512-20	00,05,12-05,20	L2-000512-20	00,0512-05,20
L1-000518-29	00,05,18-05,29	L2-000518-29	00,05,18-05,29
L1-000527-04	00,05,27-06,04	L2-000527-04	00,05,27-06,04
L1-000602-13	00,06,02-06,13	L2-000602-06	00,06,02-06,13
L1-000608-19	00,06,08-06,19	L2-000608-19	00,06,08-06,19
L1-000617-25	00,06,17-06,25	L2-000617-25	00,06,17-06,25
L1-000623-01	00,06,23-07,01	L2-000623-01	00,06,23-07,01
L1-000629-10	00,06,29-07,10	L2-000629-10	00,06,29-07,10
L1-000705-16	00,07,05-07,16	L2-000705-16	00,07,05-07,16
L1-000714-28	00,07,14-07,28	L2-000714-28	00,07,14-07,28
L1-000726-06	00,07,26-08,06	L2-000726-06	00,07,26-08,06
L1-000804-21	00,08,04-08,21	L2-000804-21	00,08,04-08,21
L1-000816-27	00,08,16-08,27	L2-000816-27	00,08,16-08,27
L1-000822-02	00,08,22-09,02	L2-000822-02	00,08,22-09,02
L1-000828-11	00,08,28-09,11	L2-000828-11	00,08,28-09,11
L1-000912-23	00,09,12-09,23	L2-000912-23	00,09,12-09,23
L1-000921-02	00,09,21-10,02	L2-000921-02	00.09.21-10.02
L1-000930-14	00,09,30-10,14	L2-000930-14	00,09,30-10,14
L1-001009-23	00,10,09,10,23	L2-001009-23	00,10,09,10,23
L1-001018-27	00,10,18-10,27	L2-001018-27	00,10,18-10,27
L1-001024-02	00,10,24-11,02	L2-001024-02	00,10,24-11,02
L1-001030-11	00,10,30-11,11	L2-001030-11	00,10,30-11,11
L1-001102-19	00,11,02-11,19	L2-001102-19	00,11,02-11,19
L1-001114-28	00,11,14-11,28	L2-001114-28	00,11,14-11,28
L1-001123-04	00,11,23-12,04	L2-001123-04	00,11,14-11,26
L1-001129-10	00,11,29-12,10	L2-001129-10	00,11,29-12,10

Notes:

(1)  The routine reports on Lageos-1 & Lageos-2 Quick-Look Normal Point (QLNP) data residual analysis for Western Pacific Laser Tracking Network (WPLTN) stations have been published by the Center for Astro-geodynamics research (CAR), Shanghai Astronomical Observatory (SHAO), Chinese Academy of Sciences (CAS) at the web site of SHAO about every two weeks since October 1, 1999. The filename of the report is "Ln-yymmdd-dd" where n is the number of Lageos, yy is the two digit year, mm is the two digit month , first dd is the start day and last dd is the end day. Any suggestions and comments will be welcome. Please contact Feng Chugan. We would like to thank Dr. Richard Eanes and Dr. John Ries , Texas University/CSR, Dr. C.K. Shum, Ohio State University, and Dr. Vladimir D. Glotov and Dr. Vladimir V. Mitrikas, MCC for their helpful discussions.

Yang Fumin  <shslr@online.sh.cn>

Feng Chugang  <fcg@center.shao.ac.cn>

CAR/SHAO, CAS

　

(2) The explaination of the analysis report of Lageos QLNP data　

　

  A. In the process of determining LAGEOS orbits , the following models have been adopted :

        1. Force models :

          - JGM-3 earth gravity field;

          - Lunar-solar and planetary gravity perturbation according to DE403/LE403;

          - Ocean tides according to CSR/Topex3.0 models including atmosphere tides;

          - Anelastic deformation due to the earth rotation (IERS);

          - Solid tides up to degree and order 4 (IERS);

          - Indirect C20 acceleration (via the Moon);

          - Solar radiation pressure (Cr adjusted) and Shadow of conic model;

          - Earth reflection radiation pressure and earth infrared radiation pressure;

          - Drag-like perturbation (Cd adjusted);

          - Empirical accelerations (including radial and transverse components);

          - General relativistic perturbation (1-body problem).

        2. Reference Frame :

          - mean equinox and equator of J2000.0 via DE403/LE403 planetary ephemerides;

          - IAU1980 nutation from DE403/LE403 added celestial pole corrections;

          - IAU1976 precession;

          - ITRF96.0 and plate motion according to NUVEL1A-NNR model for those stations whose  velocities there are not in ITRF96.0;

- Earth Orientation Parameters (EOP) (IERS) , their diurnal and semi-diurnal periodic elements (adjusted).

        3. Measurement Model :

          - Marini-Murray tropospheric correction;

          - Solid earth tide displacement according to anelastic earth model;

          - Ocean loading tide displacement (IERS);

          - Rotation deformation due to polar motion (IERS);

          - Relativistic correction .

       B. The parameters are estimated as follows:

      The satellite states, solar radiation pressure constant Cr and Cr-dot, drag-like perturbation constant Cd and Cd-dot, EOPs and their diurnal and semi-diurnal periodic elements, radial and transverse components of empirical accelerations, etc. are estimated in 3 day's arc. If the data are not insufficient in the 3 day's arc, this arc will be extended to 6 day's arc.

       C. About every station's weight:

According to the posteriori variance of long term determination LAGEOS orbits and the information of every station's observations, a station's weight has been given. A datum's weight is the same as its station.

　

Feng Chugang and Zhu Yuanlan

October 1, 1999