Satellite laser ranging at GGAO

Satellite laser ranging at GGAO

Satellite laser ranging (SLR) systems at GGAO have provided a continuous set of SLR data since 1964. GGAO is the birthplace of the world's first satellite laser ranging system, Goddard Laser (GODLAS), which became operational May 5, 1964. The knowledge gained from GODLAS spawned a new breed of laser system, the Mobile Laser System (MOBLAS). During the next fifteen years, the second and third generation MOBLAS systems were developed at GGAO and deployed to locations around the world. By 1985, the NASA Satellite Laser Ranging network of eight MOBLAS systems and four transportable laser ranging systems (TLRS) were operational as part of NASA's Crustal Dynamics Project (CDP) making scientific measurements including the determination of the movement of the Earth's tectonic plates.


  • MOBLAS-7 SLR system, one of the most accurate SLR system in the world. This SLR system is part of the International Laser Ranging Service (ILRS) network, whose primary mission is to support, through satellite and lunar laser tracking data and related products, geodetic and geophysical research activities. The MOBLAS-7 system has operated at GGAO since 1981.
  • NASA’s prototype Next Generation Satellite Laser Ranging System (NGSLR), formerly known as SLR2000, was built to demonstrate that a system using existing Commercial off-the-shelf (COTS) technology can satisfy the performance requirements as an autonomous and eye-safe photon-counting SLR station with normal point precision at the mm level.
  • 1.2 meter (48") telescope: The GGAO multi-user 1.2-meter (48”) telescope facility is used for system testing and development of next generation satellite laser ranging systems.