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GNSS data are available in daily subdirectories of the form https://cddis.nasa.gov/archive/gnss/data/daily/ yyyy / ddd , where yyyy is the four-digit year and ddd is the three-digit day of year. All data are stored in RINEX format . More information on daily data is available at https://cddis.nasa.g...

The CDDIS provides an archive of GNSS data in support of the International GNSS Service (IGS, www.igs.org). We have data in daily files (30 second sampling) going back to 1991, hourly files (30 second sampling), and high-rate files (1 second sampling). The daily data are typically delivered to the C...

An index.html file is required in order for web browsers to be able to display the contents of a directory in a proper format. This file is used when accessing the CDDIS archive through https. There is no harm in downloading this file; however, if you prefer to not retrieve the index.html file, you ...

The CDDIS acronym list is available at URL https://cddis.nasa.gov/About/Acronyms.html.

The list of satellite identifiers for SP3 orbit files is available at URL http://cddis.gsfc.nasa.gov/Techniques/sp3c_satlist.html.

The timestamp of all files in the archive refers to local time at the CDDIS (EST or EDT).

The .Z indicates the file was compressed using UNIX compression, e.g., the UNIX compress command. Users on UNIX systems can use the command uncompress to expand the file. Users on non-UNIX systems can consult the gzip web site. Note that ftp transfers of compressed files must be performed using bina...

All documents describing the data formats available through the CDDIS can be found at URL https://cddis.gsfc.nasa.gov/archive/formats.

There are several ways to access the CDDIS archive: anonymous ftp at URL ftp://cddis.gsfc.nasa.gov. NOTE this method will be discontinued in October 2020 via https at URL https://cddis.nasa.gov/archive/ via ftp-ssl using the command line and gdc.cddis.eosdis.nasa.gov Detalied information and example...

The file https://cddis.nasa.gov/archive/glonass/data/daily/ yyyy / ddd / yy n/igex ddd 0. yy n.Z ( yyyy is the four-digit year, yy is the two-digit year, ddd is the three-digit day of year) is the daily broadcast ephemeris file for the GLONASS satellites. This file is a merge of the individual site ...