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Etalon-1 and -2

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

Mission Photos:

Etalon Satellite

Mission Objectives:

Etalon are a Russian family (Etalon-1, Etalon-2) of passive geodetic satellites dedicated to satellite laser ranging. Etalon-1 was the first geodynamic satellite launched by the former Soviet Union. The Etalon spacecraft were launched in 1989 in conjunction with a pair of GLObal'naya NAvigatisionnay Sputnikovaya Sistema (GLONASS) satellites. The mission objectives were to determine a high accuracy terrestrial reference frame and earth rotation parameters, to improve the gravity field, and to improve the gravitational constant.

Mission Instrumentation:

The Etalon satellites are passive satellites. The only instrumentation is the retro-reflector array which consists of 2 different type of cube corners.

Mission Parameters:
  Etalon-1 Etalon-2
Sponsor: Russia Russia
Expected Life: hundreds of years hundreds of years
Primary Applications: geodesy geodesy
COSPAR ID: 8900103 8903903
SIC Code: 0525 4146
Satellite Catalog (NORAD) Number: 19751 20026
Launch Date: January 10, 1989 May 31, 1989
RRA Diameter: 1.294 m 1.294 m
RRA Shape: circular circular
Reflectors: 2146 corner cubes 2146 corner cubes
Orbit: Circular Circular
Inclination: 64.9 degrees 65.5 degrees
Eccentricity: 0.00061 0.00066
Perigee: 19,120 km 19,120 km
Period: 676 minutes 675 minutes
Weight: 1415 kg 1415 kg

Additional Information:


  • Andritsch F., Grahsl A., Dach R., Schildknecht T., Jaeggi A. (2020). "Simulation of tracking scenarios to LAGEOS and Etalon satellites", J. Geodesy, 94(4), 40, DOI: 10.1007/s00190-019-01327-w
  • Appleby, G.M., "Long-Arc analyses of SLR Observations of the Etalon Geodetic Satellites", Journal of Geodesy, Vol. 72, Issue 6, pp. 333-342, 1998.
  • Appleby, G.M., "Orbit determination of the Lageos and Etalon satellites - A comparison of geodetic results and orbital evolution of the Etalons", Proc. Conf. on Dynamics and Astrometry of Natural and Artificial Celestial Bodies, Poznan, Poland, pp. 333-338, 1994.
  • Dick, G., Gendt, G., Montag, H., Nischan, Th., and Sommerfeld, W., "Results of Etalon data analysis", Geodesy and Physics of the Earth-Geodetic Contributions to Geodynamics. Montag, H., Reigber, Ch. (Eds.), IAG No. 112, Potsdam, 1992, 315-318, Springer, London, 1993.
  • Mironov, N.T., Emetz. A.I., Zaharov, A.N., and Tchebotarev, V.E., "ETALON-1, -2 Center of Mass Correction and Array Reflectivity", Proc. 8th Intern. Workshop on Laser Ranging Instrumentation, Annapolis, MD, May 18-22, 1993, NASA Conference Publ. 3214, p. 6-9, 1992.
  • Sośnica K., Zajdel R., Bury G., Bosy J., Moore M., Masoumi S. (2020). "Quality assessment of experimental IGS multi-GNSS combined orbits", GPS Solutions, 24(2), 54, DOI: 10.1007/s10291-020-0965-5
  • Torrence, M.H., Dunn, P.J., and Kolenkiewicz, R., "Characteristics of the LAGEOS and ETALON Satellites Orbits", Adv. Space Res., V.16, No. 12, pp. 21-24, 1995.
  • Wiant, J., "Tunable Etalon Usage at MLRS Mcdonald Laser Ranging Station", 5th International Workshop on Laser ranging Instrumentation, Herstmonceux, U.K., published by Geodetic Institute, Univ. Bonn, p. 185, 1984.