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Satellite Laser Ranging (SLR) ILRS Combination Center (CC) Station Position and Earth Rotation Parameters (ERP) Product (weekly files, generated daily) from NASA CDDIS

Metadata Updated: September 18, 2025

This derived product set consists of Satellite Laser Ranging Final Station Position plus ERP Product (daily files, generated daily) from the NASA Crustal Dynamics Data Information System (CDDIS). SLR provides unambiguous range measurements to mm precision that can be aggregated over the global network to provide very accurate satellite orbits, time histories of station position and motion, and many other geophysical parameters. SLR operates in the optical region and is the only space geodetic technique that measures unambiguous range directly. Analysis of SLR data contributes to the terrestrial reference frame, modeling of the spatial and temporal variations of the Earth's gravitational field, and monitoring of millimeter-level variations in the location of the center of mass of the total Earth system (solid Earth-atmosphere-oceans). In addition, SLR provides precise orbit determination for spaceborne radar altimeter missions. It provides a means for sub-nanosecond global time transfer, and a basis for special tests of the Theory of General Relativity. Analysis Centers (ACs) of the International Laser Ranging Service (ILRS) retrieve SLR data on regular schedules to produce precise station positions and velocities for stations in the ILRS network. The ACs also generate Earth Orientation Parameters from the SLR data. The ILRS Analysis Center Coordinators (ACC) uses these individual AC solutions to generate the official ILRS final combined station position plus ERP products, as well as backup combination. The final products are considered the most consistent and highest quality ILRS solutions; they consist of daily station position/ERP files, generated on a daily basis with a typical delay of 2 days. All station position/ERP solution files utilize the Software Independent Exchange (SINEX) format and span 1 day from 00:00 to 23:45 UTC.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date April 11, 2025
Metadata Updated Date September 18, 2025

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date April 11, 2025
Metadata Updated Date September 18, 2025
Publisher CDDIS
Maintainer
Identifier 10.5067/SLR/SLR_ILRSSNX_001
Data Last Modified 2025-09-11
Category Earth Science
Public Access Level public
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 6d36c363-7d5d-4f9b-9e96-3bec32219daf
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://cddis.nasa.gov/archive/slr/products
Old Spatial {"EastBoundingCoordinate":180,"NorthBoundingCoordinate":90,"SouthBoundingCoordinate":-90,"WestBoundingCoordinate":-180},"CARTESIAN"
Program Code 026:000
Source Datajson Identifier True
Source Hash 25d510163ee9d57f4a77b5dd99866131e299fd3ebeb21b95d3e0450a7d7da675
Source Schema Version 1.1
Spatial
Temporal 1976-05-16/1976-05-16

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