@prefix skos: . @prefix ns0: . skos:prefLabel "LAGEOS (Laser Geodetic Satellite)"@en ; a skos:Concept ; skos:narrower . ns0:resource [ ] ; ns0:altLabel [ ] ; skos:definition """Spacecraft Brief Description LAGEOS (Laser Geodetic Satellite) was a very dense (high mass-to-area ratio) laser retroreflector satellite which provided a permanent reference point in a very stable orbit for such precision earth-dynamics measurements as 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. In conjunction with appropriate laser-tracking systems, LAGEOS permitted extreme precision-ranging measurements for both geometric mode (multilateration) and orbital dynamic mode determinations of positions of points on the earth. It was the first spacecraft dedicated exclusively to high-precision laser ranging and provided the first opportunity to acquire laser-ranging data that were not degraded by errors originating in the target satellite. The high-accuracy range measurements from this permanent-orbiting reference point were used to accomplish many extreme precision earth-dynamics measurements required by the earthquake hazard assessment and alleviation objectives of the Earth and Ocean Physics Applications Program (EOPAP). The performance in orbit of LAGEOS was limited only by degradation of the retroreflectors, so many decades of useful life can be expected. The high mass-to-area ratio and the precise, stable (attitude-independent) geometry of the spacecraft, together with the orbit, made this satellite the most precise position reference available. Because it is visible in all parts of the world and has an extended operation life in orbit, LAGEOS can serve as a fundamental standard for decades. Auxiliary Information Launch Date and Time : 1976-05-04 08:00:00 Epoch Date and Time : 1976-05-05 Orbit Type : Geocentric Apogee(km) : 5946. Perigee(km) : 5837. Inclination : 109.8 Date of last update : 1992-03-09 Group: Platform_Details Entry_ID: LAGEOS-1 Group: Platform_Identification Platform_Category: Earth Observation Satellites Platform_Series_or_Entity: LAGEOS (Laser Geodetic Satellite) Short_Name: LAGEOS-1 Long_Name: Laser Geodetic Satellite-1 End_Group Group: Synonymous_Platform_Names Short_Name: LAGEOS-1 End_Group Group: Platform_Associated_Instruments Short_Name: LASER TRACKING REFLECTOR End_Group Group: Orbit Orbit_Inclination: 109.90 deg Period: 225.50 min Perigee: 5,837 km Apogee: 5,947 km End_Group Creation_Date: 2007-10-10 Online_Resource: http://msl.jpl.nasa.gov/QuickLooks/lageosQL.html Online_Resource: http://nasascience.nasa.gov/missions/lageos-1-2 Online_Resource: http://ilrs.gsfc.nasa.gov/satellite_missions/list_of_satellites/lag1_general.html Sample_Image: http://msl.jpl.nasa.gov/QuickLooks/pictures/lageos.gif Group: Platform_Logistics Launch_Date: 1976-05-04 Launch_Site: Vandenberg Air Force Base, USA Design_Life: 50 years Primary_Sponsor: USA/NASA End_Group End_Group"""@en ; skos:prefLabel "LAGEOS-1"@en ; skos:inScheme ; skos:broader ; a skos:Concept .