+ Home

One area that INDIGO can assist the user community is in the review and coordination of site information available through the IAG services.

Web sites. Each geodetic service provides web access to information about network stations:

• IGS - network map and links to individual site information pages
• ILRS - network map and links to individual site information pages
• IVS - network map and site information pages
• IDS - network map and links to individual site information pages

Site metadata tables. Tables of IGS, ILRS, IVS, and IDS sites have been created to show site metadata currently available in CDDIS data base:

• Full list of site occupation information (ordered by country html/text, ordered by site html/text) from CDDIS metadata (all historic as well as current sites)
• List of co-located sites only (ordered by country html/text, ordered by site html/text) from CDDIS metadata

Site configuration. The four geodetic services utilize some form of site log to describe the installation of network stations. These logs contain common elements across the services:

• Site identification
  • Site name
  • Code
  • DOMES number
• Location information
  • Site description (brief)
  • Approximate coordinates
  • Local ties
  • Collocation information
  • Monument description
• Instrumentation
  • Technique specific
  • Time/frequency standards
  • Meteorological
• Contact information

The logs are archived and made available through the service's central bureau/coordinating center web/ftp sites. The responsibility of the creation and maintenance of the site logs resides with the station operations staff. Any changes to the site configuration (as documented in the log) must be recorded in the site log and forwarded to the service. Typically, the station staff downloads the current log from the central bureau/coordinating center website, makes necessary changes along with the time period of the changes, and uploads the new version through the appropriate channel. Service staff reviews the submitted log, archives the old log, and makes the new log available to the public.

General site information/site cataloging efforts. Catalogs of site information have been in development for the last 20+ years. From 1985 through the early 1990's, the space geodesy group at GSFC worked on a hardcopy catalog of sites supporting the Crustal Dynamics Project. The latest version of this catalog was published in 1993: Bryant, Mark A., Carey E. Noll, NASA Space Geodesy Project: Catalogue of Site Information. NASA TM 4482, March, 1993. An online version is available at http://cddis.gsfc.nasa.gov/site_cat/. Information about each site participating in the CDP was gathered and categorized as follows:

• General site information
  • Numbering
  • Location
  • Geographic region
  • Tectonic plate
  • Primary scientific purposes
  • Site description
  • Site topo map
• Geological information
  • Province
  • Local geology
• Monument information (for each monument utilized by space geodesy)
  • Numbering
  • Type
  • Inscription
  • System
  • Coordinates
  • Differential coordinates
• Site sketch
• Occupation history

A more recent version of the catalog was started in 1998 as an online, web-based version. The sections from the previous version of the catalog were included and expanded of the following items:

• Contact information
  • Name
  • Ownership
• Photos
• Monument information
  • Detailed description
• Site Sketch
• Horizon profile
• Occupation information
  • Footprint surveys

The IERS is responsible for the International Terrestrial Reference System (ITRS) and its realization, the International Terrestrial Reference Frame (ITRF). A website of site information supporting the ITRF is available at http://itrf.ensg.ign.fr/. This new site provides the following site information:

• DOMES number database
• Local ties used in the ITRF
• ITRF products
  • ITRF solutions
  • Transformation parameters
• Site information
  • Numbering
  • Location
  • Local ties
  • ITRF station positions and velociities