Global and Regional Network Maps
zoom in on imagezoom out on image


  • GNSS
  • SLR
  • VLBI
Learn about Techniques
CDDIS upgrading to a new system
01 June 2016
In the near future CDDIS will be upgrading to a new system. One important change involves how files are uploaded to our system. CDDIS will NO LONGER SUPPORT the current ftp upload procedures in our new environment. Anyone who submits files for archive in the CDDIS must update their procedures.
Read more

Now 40, NASA's LAGEOS Set the Bar for Studies of Earth
04 May 2016
On May 4, 1976, NASA launched a cannonball-shaped satellite that transformed studies of Earth’s shape, rotation and gravity field.

LAGEOS – short for Laser Geodynamic Satellite – was the first NASA orbiter dedicated to the precision measurement technique called laser ranging. With it, scientists have measured the movement of Earth’s tectonic plates, detected irregularities in the rotation of the planet, weighed it, and tracked small shifts in its center of mass.

Small deviations in the satellite’s orbit were used to develop early models of Earth’s gravitational field. Further perturbations in the orbit helped explain how sunlight heating small objects can affect their orbits, including near-Earth asteroids.
Read more

NASA Station Leads Way for Improved Measurements of Earth Orientation, Shape
10 Mar 2016
NASA has demonstrated the success of advanced technology for making precise measurements of Earth’s orientation and rotation – information that helps provide a foundation for navigation of all space missions and for geophysical studies of our planet. The technology includes a new class of radio antenna and electronics that provide broadband capabilities for Very Long Baseline Interferometry, or VLBI. This technique is used to make precise measurements of Earth in space and time.
Read more

NASA Contributes to Global Standard for Navigation, Studies of Earth
25 Feb 2016
The surface of Earth is constantly being reshaped by earthquakes, volcanic eruptions, landslides, floods, changes in sea levels and ice sheets, and other processes. Since some of these changes amount to only millimeters per year, scientists must make very precise measurements of the landscape and ocean in space and time in order to study their evolution and help mitigate their impacts.
Read more

06 Jan 2016
Starting with data from 2016, all RINEX V3 data using the RINEX V3 filenaming convention will now be made available in the operational GNSS data archives at the CDDIS. This change has been implemented at the IGS data centers in accordance with the IGS RINEX 3 transition plan (http://bit.ly/1Md7VhU).
Read more

Brief network outages at GSFC on December 19, 2015
11 Dec 2015
Work will be performed on the NASA GSFC network infrastructure from 03:00 p.m. (20:00 UTC), Saturday, December 19, 2015 through 03:00 a.m. (08:00 UTC) on Sunday, December 20. Users can expect 10-15 minute interruptions during that time period.
Read more
Weekly GNSS data holdings (daily, hourly, high-rate)

Weekly SLR normal point pass segment totals (by satellite, LAGEOS and ETALON only)

Archive Explorer Tool Search the CDDIS data archive for SLR, DORIS, or GNSS data.

Site Log Viewer Tool Browse SLR, DORIS, or GNSS site logs by site or across the network.

Site Selection Tool Search and discover CDDIS data holdings using the GSAC-WS.