NASA CDDIS: Daily GNSS Broadcast Ephemeris and Observation Data

NASA's Crustal Dynamics Data Information System (CDDIS) provides daily ground-based Global Navigation Satellite System observation and broadcast ephemeris data. The dataset includes 30-second sampled observation data from GPS, GLONASS, Galileo, Beidou, QZSS, IRNSS, and SBAS since 2011, stored in RINEX format. These files originate from a global permanent network of receivers, supporting precise geospatial positioning and Earth science research.

Use Cases

• Precise geodetic positioning analysis based on multi-GNSS observation data.
• Satellite orbit and clock error modeling using broadcast ephemeris data.
• Crustal motion and plate tectonics studies leveraging long-term time-series data.
• Atmospheric science research utilizing GNSS signal delay measurements.
• Validation and calibration of space-based augmentation systems (SBAS).

Strengths

• Data originates from the authoritative NASA CDDIS archive.
• Includes a multi-GNSS constellation (GPS, GLONASS, Galileo, Beidou, QZSS, IRNSS, SBAS) since 2011.
• Provides high-temporal-resolution (30-second sampling) observation data.

Limitations

• Specific column names and dataset size/row counts are not provided in the metadata.
• One platform lists a license ('other-license-specified') while another lists 'None', creating ambiguity.
• The metadata is sparse on technical details like file structure beyond the RINEX format.

Provenance

Source

NASA Crustal Dynamics Data Information System (CDDIS)

Collection Method

Collected from a global permanent network of ground-based GNSS receivers.

Time Range

Data available at least since 2011, with daily files continuing to the present.

Freshness

Last updated on 2026-04-10 according to datagov.

Geography

Global coverage from a network of permanent ground stations.