Global and Regional Network Maps
LARES + LAGEOS 1&2 Lense-Thirring results selected as EPJ-C cover
19 July 2016The article, "A test of general relativity using the LARES and LAGEOS satellites and a GRACE Earth gravity model," (Ciufolini et. al.) has been published in the March 2016 issue of the European Physical Journal-C. Furthermore, a figure from this paper has been selected for the cover of that issue.
NASA Space Geodesy Data for Precise Orbit Determination of Altimeter Satellites Webinar (NASA Earthdata webinar series)
29 June 2016Over the last 25 years, ocean radar altimeter satellites have revolutionized our understanding of the world’s oceans. Today six altimeter satellites from different national and international space agencies synoptically measure the ocean surface topography in order to determine how the ocean surface changes with time. The heart of the altimeter measurement is the precise determination of the orbit reference which is used as the basis from which the changes in the ocean surface are determined. We now routinely determine the orbits of the joint NASA/CNES/NOAA/EUMETSAT missions Jason-2 and Jason-3 with a radial RMS precision of 1 cm.
CDDIS upgrading to a new system
01 June 2016In 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.
Now 40, NASA's LAGEOS Set the Bar for Studies of Earth
04 May 2016On 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.
NASA Station Leads Way for Improved Measurements of Earth Orientation, Shape
10 Mar 2016NASA 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.
NASA Contributes to Global Standard for Navigation, Studies of Earth
25 Feb 2016The 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.