Skip to main content

SLR Data Holdings

The Satellite Laser Ranging (SLR) data archived in NASA’s Crustal Dynamics Data Information System (CDDIS) are in the form of on-site normal point and full-rate data. In the early days of laser ranging data analysis, scientists typically required SLR full-rate data; these data included all valid points or returns from the satellite. Since 1988, SLR normal points have been produced from the global full-rate data set.

Normal point data are compressed data using sampling over time based upon the presence of some minimum number of data points in the sampling interval. The monthly data volume is considerably reduced. Since the early 1990's, normal point are generated on-site by laser ranging systems and transmitted daily (and sometimes hourly) to a regional processing center via electronic means.

Data Summary

The data from each satellite are stored in separate files and directories, by satellite. Each file contains all data received during the last 24-hour period. Additionally, a single file containing all data received during the last 24 hours is available.

Data from the global laser ranging network are organized in subdirectories by file content (normal points, full-rate), satellite, and year.

SLR Data Holdings

Spatial coverage

Temporal coverage

Data volume

  • Normal point data: ~1.25 Mbyte/day, 40 Mbyte/month
  • Full-rate SLR data: ~10 Mbytes/day (compressed)

Data Formats

  • Normal point data: Consolidated Laser Ranging Data (CRD) format, 2012 through present; ILRS Normal Point data format (formerly known as the CSTG format) prior to 2012
  • Full-rate data: Consolidated Laser Ranging Data (CRD) format, 2012 through present; ILRS Full-Rate Data format (formerly known as the MERIT-II format, V2/V3) prior to 2012

Datasets

View All Datasets
Quick Filters
No Results

Frequently Asked Questions

Earthdata Forum

Our online forum provides a space for users to browse thousands of FAQs about research needs, data, and data applications. You can also submit new questions for our experts to answer.

Submit Questions to Earthdata Forumand View Expert Responses

Earthdata
Forum