NASA will be performing network maintenance on Wednesday, November 20, 2024, between 11:00 AM EST and 1:00 PM EST (16:00 to 18:00 UTC). There will be two periods of about five minutes of disruption. During these peroids, the ILRS website will be unavailable during the outages. If you experience problems outside this window, contact support-cddis@nasa.gov.

close window
general navigation structure general satellite info ilrs support retroreflector info center of mass site performance info

TOPEX/Poseidon

Jump to: Mission Objectives, Mission Instrumentation, Mission Parameters, Additional Information

Mission Photos:

TOPEX
Courtesy of JPL

Mission Objectives:

Ocean TOPography Experiment (TOPEX)/Poseidon, also known as Poseidon and it's follow on mission, Jason, were designed to explore ocean circulation and its interaction with the atmosphere. It complements a number of international oceanographic and meteorological programs, including the World Circulation Experiment (WOCE) and the Tropical Ocean and Global Atmosphere (TOGA) Program, both of which are sponsored by the World Climate Research Program (WCRP). TOPEX/Poseidon's three-year prime mission ended in fall 1995 and the mission successfully moved into its extended observational phase. Jason, launched in 2001, continues this program of long-term observations of ocean circulation from space.

TOPEX/Poseidon was a joint project between the National Aeronautics and Space Administration (NASA) and the French Space Agency, Centre National d'Etudes Spatiales (CNES). NASA provided the satellite bus and five instruments with their associated ground elements. NASA's Jet Propulsion Laboratory (JPL) was responsible for project management, and operated the satellite through NASA's Tracking and Data Relay Satellite System. CNES furnished two instruments with their associated ground elements and a dedicated launch on a Ariane 42P rocket. Both CNES and NASA provided precision orbit determination and continue to process and distribute data to the science investigators.

TOPEX/Poseidon measured sea level along the same path every 10 days using the dual frequency altimeter developed by NASA and the CNES single frequency solid-state altimeter. This information is used to relate changes in ocean currents with atmospheric and climate patterns. Measurements from NASA's Microwave Radiometer provide estimates of the total water-vapor content in the atmosphere, which is used to correct errors in the altimeter measurements. Three independent techniques (SLR, DORIS, and GPS) determine the satellite altitude, used to calibrate the altimeters. These combined measurements allow scientists to chart the height of the seas across ocean basins with an accuracy of 3 centimeters (1.1 inches).

Mission Instrumentation:

TOPEX Instruments

TOPEX had the following instrumentation onboard:

  • Tracking and data relay satellite transmitter
  • Microwave radiometer
  • DORIS dual frequency system receiver
  • Single and dual-frequency altimeters
  • GPS receiver
  • Retro-reflector array
Mission Parameters:
Sponsor: NASA and CNES
Expected Life: Several years
Primary Applications: ocean circulation
Primary SLR Applications: calibration of satellite altimeter
COSPAR ID: 9205201
SIC Code: 4377
Satellite Catalog (NORAD) Number: 22076
Launch Date: 10-Aug-92
RRA Diameter: 150 cm array
RRA Shape: annulus array
Reflectors: 192 corner cubes
Orbit: Circular
Inclination: 66 degrees
Eccentricity: 0.000
Perigee: 1340 km
Period: 112 minutes
Weight: 2,400 kg

Additional Information:

Web sites:

Publications:

  • Antreasian, P.G., and Rosborough, G.W., "Prediction of radiant energy forces on the TOPEX/Poseidon spacecraft," J. Spacecraft and Rockets, 29(1), pp. 81-90, 1992.
  • Behn, M.D. and Zuber, M.T., "A comparison of ocean topography derived from the shuttle laser altimeter-01 and TOPEX/Poseidon", IEEE T GEOSCI REMOTE Vol. 38, Issue 3, May, pp. 1425-1438, 2000.
  • Bertiger, W.I., Bar-Sever, Y.E., Christensen, E.J., Davis, E.S., Guinn, J.R., Haines, B.J., Ibanez-Meier, R.W., Jee, J.R., Lichten, S.M., Melbourne, W.G., Muellerschoen, R.J,. Munson, T.N,. Vigue, Y., Wu, S.C., Yunck, T.P., Schutz, B.E., Abusali, P.A.M., Rim, H.J., Watkins, M.M. and Willis, P., "GPS precise tracking of TOPEX/Poseidon: Results and implications", J. Geophys. Res., TOPEX/Poseidon Special Issue, in press, 1994.
  • Born, G.H., Stewart, R.H. and Yamarone, C.A., "TOPEX-A Spaceborne Ocean Observing System", Reprint from Monitoring Earth's Ocean, Land, and Atmosphere from Space-Sensors, Systems, and Applications, Ed. by A. Schnapf, Vol. 97 of Progress in Astronautics and Aeronautics Series, AIAA, 1985.
  • Born, G.H., Wunsch, C. and Yamarone, C.A., "TOPEX: Observing the Oceans from Space", EOS, Vol. 65, pp. 433-434, 1984.
  • Casotto, S., "Ocean tide models for TOPEX precision orbit determination", CSR-89-4, Center for Space Research, The University of Texas at Austin, December 1989.
  • Christensen, E.J., Haines, B.J., McColl, K.C. and Nerem, R.S., "Observations of geographically correlated orbit errors for TOPEX/Poseidon using the Global Positioning System", Geophys. Res. Lett., in press, 1994.
  • Davis, G.W., Ries, J.C. and Tapley, B.D., "Preliminary accuracy assessment of the DORIS tracking system on TOPEX/Poseidon", Proc. AAS/AIAA Astrodynamics Specialist Conference, Victoria, B.C., Canada, August, 1993.
  • Eanes, R.J., "Diurnal and semidiurnal tides from TOPEX/Poseidon altimetry", EOS, paper G32B-6 given at the Spring Meeting of the AGU, Baltimore, MD, 1994.
  • Eanes, R.J., and Ries, J.C., "Monthly and Constant Velocity Station Positions from LAGEOS and TOPEX/Poseidon", presented at ITRF2000 Workshop, Paris, France, November 2-3, 2000.
  • Frauenholz, R.B., Hamilton, T.W., Shapiro, B.E., and Bhat, R.S., "The role of anomalous satellite-fixed accelerations in TOPEX/Poseidon orbit maintenance", Proc. of AAS/AIAA Astrodynamics Specialist Conference, Victoria, B.C., Canada, August , 1993.
  • Fu, L.L., Christensen, E.J., Lefebvre, M., and Menard, Y., "TOPEX/Poseidon mission overview", J. Geophys. Res. 99 , C12 , p. 24,369-24,382, 1994.
  • Kar, S., and Ries, J.C., "The effect of solar array warping on TOPEX orbit determination", CSR-TM-93-02, Center for Space Research, The University of Texas at Austin, April , 1993.
  • Lemoine, F., Zelensky, N., Luthcke, S., Rowlands, D., Chinn, D, Beckley, B., Klosko, S., "13 Years of TOPEX/Poseidon Precision Orbit Determination and the 10-fold improvement in expected orbit accuracy", AIAA/AAS Astrodynamics Conference, Keystone, Colorado, August 21-24, 2006.
  • Lerch, F.J., Doll, C.E., Marshall, J.A., Luthcke, S.B., Williamson, R.G., Klosko, S.M., McCarthy, J.J., and Eddy, W.F., "Precision Orbit Determination for TOPEX/Poseidon Using TDRSS Doppler Tracking Data", -reprinted from Adv. Space. Res., V.16, No. 12, pp. 89-92, 1995.
  • Luthcke, S.B., and Marshall, J.A., "Nonconservative force model parameter estimation strategy for TOPEX/Poseidon precision orbit determination", NASA Tech. Memo. 104575, pp. 42, November, 1992.
  • Marshall, J.A., Chinn, D.S., Rachlin, K.E., and Zelensky, N.P., "The spatial and temporal characteristics of TOPEX/Poseidon radial orbit error", EOS, paper G31A-8, presented at the Spring Meeting of the AGU, Baltimore, MD, c., 1994.
  • Marshall, J.A., and Luthcke, S.B., "Nonconservative force model performance for TOPEX/Poseidon precision orbit determination", AAS-93-268, Proc. AAS/GSFC International Symposium on Space Flight Dynamics, 1, April 1993. Marshall, J.A., and S. B. Luthcke, Modeling radiation forces acting on TOPEX/Poseidon for precision orbit determination, J. Spacecraft and Rockets, 31(1), 89-105, a, 1994.
  • Marshall, J.A., and Luthcke, S.B., "Radiative force model performance for TOPEX/Poseidon orbit determination", J. Astro. Sci., 41, 1, in press, b, 1994.
  • Murdoch, A., and Decker, W., "Crustal Dynamics Satellite Laser Ranging Network Preliminary TOPEX/Poseidon Laser Network Support Plan", Bendix Field Engineering, NASA rpt. CDSLR-03-0002, approx. 160 pp. , 1989.
  • Nerem, R.S., Lerch, F.J., Marshall, J.A., Pavlis, E.C., Putney, B.H., Chan, J.C., Klosko, S.M., Luthcke, S.B., Patel, G.B., Pavlis, N.K., Williamson, R.G., Tapley, B.D., Eanes, R.J., Ries, J.C., Schutz, B.E., Shum, C.K., Watkins, M.M., Rapp, R.H., Biancale, R., and Nouel, F., "Gravity model development for TOPEX/Poseidon: Joint Gravity Model-1 and 2", J. Geophys. Res., TOPEX/Poseidon Special Issue, in press, a, 1994.
  • Nerem, R.S., Putney, B.H., Marshall, J.A., Lerch, F.J., Pavlis, E.C., Klosko, S.M., Luthcke, S.B., Patel, G.B., Williamson, R.G., and Zelensky, N.P., "Expected Orbit Determination Performance for the TOPEX/Poseidon Mission", IEEE Trans. Geosci. Remote Sensing, V.31, pp. 333-354, 1993.
  • Nerem, R.S., et al., "Joint Gravity Model (JGM-2)", paper given at the TOPEX/Poseidon Verification Workshop Meeting, JPL, Pasadena, CA, February, 1993.
  • Neubert, R., "Satellite Signature Model: Application to LAGEOS and TOPEX", In: Proc. Annual EUROLAS Meeting, Munich, 1995.
  • Nouel, F., Berthias, J.P., Deleuze, M., Guitart, A., Laudet, P., Piuzzi, A., Pradines, D., Valorge, C., Dejoie, C., Susini, M.F., and Taburiau, D., "Precise CNES orbits for TOPEX/Poseidon: Is reaching 2 cm still a challenge?", J. Geophys. Res., TOPEX/Poseidon Special Issue, in press, 1994.
  • Pavlis, N.K., Beckley, B., and Sanchez, B., "Estimation of ocean tides from TOPEX altimetry", EOS, paper G31A-7, presented at the Spring Meeting of the AGU, Baltimore, MD, 1994.
  • Pearlman, M., "A report on the Topex/Poseidon mission NASA Solid Earth Sciences (SES) program", Proc. of the 7th International Workshop on Laser Ranging Instrumentation, Matera, Italy October 2-8, published by OCA/CERGA, Grasse, France, p. 47, 1989.
  • Peltzer, A., Gilbreath, G., Roberts, D., and Barnds, W., "Study to Determine the Accuracy in Orbital Analysis of TOPEX Using a Single SLR Site", Proc. of the 9th International Workshop on Laser Ranging Instrumentation, Australian Government Publishing Service, Canberra, p . 346, 1994.
  • Putney, B.H., Marshall, J.A., Nerem, R.S., Lerch, F.J., Chinn, D.S., Johnson, C.C., Klosko, S.M., Luthcke, S.B., Rachlin, K.E., Williams, T.A., Williamson, R.G., and Zelensky, N.P., "Precise orbit determination for the TOPEX/Poseidon mission", Proc. of AAS/AIAA Astrodynamics Specialist Conference, Victoria, B.C., Canada, August , 1993.
  • Rapp, R.H., Nerem, R.S., Shum, C.K., Klosko, S.M., and Williamson, R.G., "Consideration of Permanent Tidal Deformation in the Orbit Determination and Data Analysis for the TOPEX/Poseidon Mission", NASA Tech. Memo. 100775, January, 1991.
  • Ray, R.D., "Global Ocean Tide Models on the Eve of TOPEX/Poseidon", IEEE Trans. Geosci. Remote Sensing, V.31, pp. 355-364, 1993.
  • Ray, R.D., Sanchez, B.V., and Cartwright, D.E., "Some extensions to the response method of tidal analysis applied to TOPEX/Poseidon altimetry", EOS, paper G31A-5, presented at the Spring Meeting of the AGU, Baltimore, MD, 1994.
  • Ries, J.C, and Tapley, B.D., "Centimeter Level Orbit Determination for the TOPEX/Poseidon Altimeter Satellite", Proc. AAS/AIAA Spaceflight Mechanics Meeting, Breckenridge, CO, February 7-10, 1999.
  • Sagnières L.B.M., Sharf I., Deleflie F., "Simulation of long-term rotational dynamics of large space debris: A TOPEX/Poseidon case study", Adv. Space Res., 65(4), 1182-1195, DOI: 10.1016/j.asr.2019.11.021
  • Schrama, E.J., and Ray, R.D., "A preliminary tidal analysis of TOPEX/Poseidon altimetry", J. Geophys. Res., TOPEX/Poseidon Special Issue, in press, 1994.
  • Schutz, B.E., Tapley, B.D., Abusali, P.A.M., and Rim, H.J., "Dynamic orbit determination using GPS measurements from TOPEX/Poseidon", Geophys. Res. Lett., in press, 1994.
  • Schwartz, J.A., "Laser Ranging Error Budget for the TOPEX/Poseidon Satellite", Applied Optics, V. 29, pp. 3590-3596, 1990.
  • Shum, C.K., (ed.), "TOPEX Gravity Model Improvement Meeting Proc.", - Center for Space Research Rpt. No. CSR-87-3, 1987.
  • Tapley, B.D., Schutz, B.E., Ries, J.C., and Shum, C.K., "Precision orbit determination for TOPEX", Adv. Space Res., 10(3-4), 239-247, 1990.
  • Tapley, B.D., et al., "Precision orbit determination for TOPEX/Poseidon", J. Geophys. Res., TOPEX/Poseidon Special Issue, in press, a, 1994.
  • Varghese, T., "Analysis of TOPEX Laser Retroreflector Array Characteristics", Proc. 8th Intern. Workshop on Laser Ranging Instrumentation, Annapolis, MD, May 18-22, 1993, NASA Conference Publ. 3214, p. 6-47, 1992.
  • Varghese, T., Zagwodzki, T.W., Mcgarry, J.F., Degnan, J.J., and Conklin, B., "On-Orbit Measurement of TOPEX Impulse Response: Assessment of Coherent Interaction and Verification of Range Correction", Proc. of the 10th International Workshop on Laser Ranging Instrumentation, Shanghai Observatory, Chinese Academy of Sciences, Shanghai, China, November 11-15, p. 242, 1996.
  • Watkins, M.M., Davis, G.W., and Ries, J.C., "Precise station coordinate determination from DORIS tracking of the TOPEX/Poseidon satellite", Proc. AAS/AIAA Astrodynamics Specialist Conference, Victoria, B.C., Canada, August 16-19, 1993.
  • Yunck, T.P., Bertiger, W.I., Wu, S.C., Bar-Sever, Y.E., Christiansen, E.J., Haines, B.J., Lichten, S.M., Muellerschoen, R.J., and Willis, P., "First Assessment of GPS-Based Reduced Dynamic Orbit Determination on TOPEX/Poseidon", Geophys. Res. Let., V.21, pp. 541-544, 1994.
  • Zeitlhöfler J., Bloßfeld M., Rudenko S., et al. (2022), "Station-dependent satellite laser ranging measurement corrections for TOPEX/Poseidon", Adv. Space Res., DOI: 10.1016/j.asr.2022.09.002.