The Laser Geodynamic Satellite-2 (LAGEOS-2) was built by the Italian Space Agency and launched on October 22, 1992. It is designed for high-precision laser ranging.
LAGEOS is a passive platform with no power, communications, or moving parts. LAGEOS platform "operations" consist of simply the generation of the orbit predictions necessary for ground stations to acquire and track the platform.
The LAGEOS platform is covered with 426 cube corner reflectors with all but four of these reflectors made with fused silica glass. The other four reflectors are made of germanium to obtain measurements in the infrared for experimental studies of reflectivity and satellite orientation.
LAGEOS-2 and its sister platform LAGEOS-1 are very dense (high mass-to-area ratio). LAGEOS-1 and -2 provide a permanent reference point in a very stable orbit for precision Earth-dynamics measurements including crustal motions, regional strains, fault motions, polar motion and Earth-rotation variations, solid Earth tides, and other kinematic and dynamic parameters associated with earthquake assessment and alleviation.
LAGEOS did not carry any instrument to collect data. Rather, it was covered in reflectors designed for high-precision laser ranging.
Platform characteristics:
| Launch Date: | October 22, 1992 |
| Diameter: | 60 cm |
| Shape: | Sphere |
| Reflectors: | 426 corner cubes |
| Orbit: | Circular |
| Inclination: | 52.64° |
| Eccentricity: | 0.0135 |
| Perigee: | 5,620 km |
| Period: | 223 minutes |
| Weight: | 405.38 kg |
LAGEOS-2 did not acquire any data as it is a passive platform. Metrics acquired from LAGEOS are laser range values. NASA's Crustal Dynamics Data Information System (CDDIS) has a naming convention for precise orbit products from LAGEOS and similar satellite laser ranging (SLR) products:
The starting directory for these files is:
https://cddis.nasa.gov/archive/slr/products/orbits/
Append the following directory and file names to the starting directory:
SATNAME/YYMMDD/ACNAME.orb.SATNAME.YYMMDD.vNN.sp3.gz doi:10.5067/SLR/SLR_ILRSORB_001.
| Code | Meaning |
| SATNAME | etalon1, etalon2, lageos1, lageos2, ajisai, lares, larets, starlette, stella |
| YY | 2-digit year |
| MM | 2-digit month |
| DD | 2-digit day |
| ACNAME | bkg Bundesamt für Kartographie und Geodäesie (BKG) Germany dgfi Deutsches Geodätisches Forschungsinstitut (DGFI) Germany esa ESA/ESOC, Germany gfz Helmholtz Centre Potsdam German Research Centre for Geosciences (GFZ), Germany ilrsa ILRS primary combination solution - Italian Space Agency, Centro di Geodesia Spaziale "G. Colombo" (ASI/CGS), Italy ilrsb ILRS backup combination solution - Joint Center for Earth System Technology/Goddard Space Flight Center (JCET/GSFC) Greenbelt, Maryland, USA asi Italian Space Agency, Centro di Geodesia Spaziale "G. Colombo" (ASI/CGS), Italy jcet Joint Center for Earth System Technology/Goddard Space Flight Center (JCET/GSFC) Greenbelt, Maryland, USA ngsf NERC Space Geodesy Facility (NSGF) formely RGO Satellite Laser Ranging Group, United Kingdom |
| NN | numeric version number |
| gz | gzip compressed file |
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