A passive satellite , it is a sphere of aluminium covered with retroreflectors to reflect laser ranging beams emitted from ground stations on Earth .
In October 1992 NASA launched LAGEOS - 2 ( following LAGEOS - 1 launched in 1976 ) in cooperation with ASI .
A passive satellite , ASI is a sphere of aluminium covered with retroreflectors to reflect laser ranging beams emitted from ground stations on Earth .
In October 1992 NASA launched LAGEOS - 2 ( following LAGEOS - 1 launched in 1976 ) in cooperation with ASI .