DS 
EEE SN EU a SE TN Se PAR I C EI 
' — March 15, 1978 
LAGEOS (Laser Geodynamic Satellite) ‘ 
LAUNCH DATE: May 4, 1976 
ORBIT: Circular, highly stable (Drag effects of solar radiation, | 
traces of Earth's atmosphere, or variation in ( 
gravity field minimized by density and small size.) | 
Altitude: 5790. km 
Inclination: 110° 
SENSORS: 426 retroreflectors made of high quality fused silica 
passively reflect laser light aimed from Earth. 
DESCRIPTION: Spherical, retroreflective, passive satellite 
Diameter: 60 cm 
Weight: 411 kg 
PURPOSE: Earth dynamics; precise measurements over large distances 
(to within 0.1 m now, and to within 20 mm when measurement 
techniques are perfected) 
Plate tectonics; measurements of rate and direction of 
movement of continental plates 
REMARKS: Useful life expectance, a few hundred years. 
CONTACT: (For data or information) t (4 
Chris C. Stephanides 
NASA/GSFC Code 943 
Greenbelt, Md. 20771 
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