May 4, 1976 (LAGEOS 1) and October 22, 1992 (LAGEOS 2)
Where are LAGEOS 1&2?
3,728 miles (6,000 km) above Earth
What do LAGEOS 1&2 do?
LAGEOS 1 & 2 (short for Laser Geodynamics Satellites) help scientists make measurements used for studies of Earth’s shape and continental drift. Each LAGEOS satellite is like a big ball with 426 reflectors all over its surface. If scientists shine a pulsing laser from Earth, the laser will reflect off of the satellite and return to the ground. Using this information, scientists can make very accurate distance measurements because of the laser’s round-trip travel time.