The purpose of this page of the CDDIS web site is to post new items, activities, data sets, etc. of interest to the CDDIS user community. Users should also consult the list of upcoming meetings of interest to the space geodesy community.
Modification to CDDIS Directory Structure for GNSS Data in RINEX V3 Format (23-Nov-2009):
IThe CDDIS archive structure for GNSS data in RINEX V3 format was modified today. All data can now be found in subdirectories by type, year, and day of year as follows:
The change was made to make the directory structure more in line with those of other types of test data (e.g., l2ctest, swrxtest, etc.). At this time, only hourly data in RINEX V3 format are available. Please contact me if you have any questions or problems.
DAAC Annual Article Featuring CDDIS Data Published (01-Nov-2009):
A feature article ("A Snag in Space-TIme") has recently been published discussing the use of laser ranging data (available through the CDDIS) in studying Einstein's general theory of relativy, particularly research conducted by Ignazio Ciufolini and Erricos Pavlis. The article is part of the 2009 issue of Sensing Our Planet: NASA Earth Science Research Feature, an annual publication of the Earth Observing System Data and Information System (EOSDIS).
NASA Earth Science Data and Services Survey for 2009 (02-Sep-2009):
In the next few days, many users of the CDDIS will receive an email from CFI Group on behalf of NASA. This message will ask recipients to complete a survey of users of NASA Earth science data and services, which includes the CDDIS. The purpose of this survey is to help NASA and the data centers assess customer satisfaction and improve future services.
The American Customer Satisfaction Index (ACSI) is the #1 national economic indicator of customer satisfaction. Over 70 U.S. Federal Government agencies have used the ACSI to measure more than 120 programs/services. The survey is being conducted by CFI Group under contract with the Department of Treasury's Federal Consulting Group, Executive Agent in government for the ACSI. We ask recipients to please consider responding to this survey; the resulting input will help us to better serve our user community.
Thank you in advance to all of who are willing to spend a few minutes to complete the survey.
LRO-LR First Successful Returns (02-Jul-2009):
The first two successful SLR passes between a terrestrial ground station and a spacecraft orbiting the Moon were obtained on July 1, and July 2, 2009 between the NGSLR station at Greenbelt, Maryland, USA, and the Lunar Reconnaissance Orbiter (LRO). The first pass was obtained between 22:11 and approximately 23:10 UTC on July 1, 2009. LRO is in a low-altitude, near-polar commissioning orbit around the Moon. All spacecraft systems are being carefully and systematically checked. The Lunar Ranging data to LRO are being analyzed and validated and the data flow and system operations for operational ranging to LRO are being tested. The LR system on LRO will supplement the S Band (radio) tracking system for purposes of precision orbit determination and gravity field improvement. The CDDIS is hosting the LRO-LR general information and real-time monitoring websites.
IAG Service Networks Layers for Google Earth (22-Apr-2009):
Several layers for the IGS, ILRS, IVS, and IDS have been developed for display in the Google Earth application. These layers are contained in text files available for download from the CDDIS:
- IGS: http://cddis.gsfc.nasa.gov/kml/igs_layer.kml
- ILRS: http://cddis.gsfc.nasa.gov/kml/ilrs_layer.kml
- IVS: http://cddis.gsfc.nasa.gov/kml/ivs_layer.kml
- IDS: http://cddis.gsfc.nasa.gov/kml/ids_layer.kml
To display layers in your local version of the Google Earth application:
- Enter above links in browser to download the files from CDDIS
- After download, launch Google Earth application
- In Google Earth: File-> Open-> <<KML file>>
- Layer appears in left under Places
The sites are listed within each layer as well as the service logo and legend. Any of these items can be individually displayed or removed.
Recent CDDIS Poster Publications (01-Feb-2009):
Several posters were have been presented in recent months and may be of interest to a larger community:
- C. Noll, "The Global GNSS, SLR, VLBI, and DORIS Networks and their Support of GGOS: IGS+ ILRS+IVS+IDS", Eos Trans. AGU, 89(53), Fall Meet. Suppl., Abstract G33A-066, December 2008. (PDF poster | 9.4 Mbytes)
- C. Noll, "SLR, GNSS, VLBI and DORIS Networks: ILRS+IGS+IVS+IDS", 16th International Workshop on Laser Ranging, Poznan, Poland, October 2008. (PDF poster | 5 Mbytes)
- C. Noll, "Satellite Laser Ranging Tracking through the Years", 16th International Workshop on Laser Ranging, Poznan, Poland, October 2008. (PDF poster | 3.7 Mbytes)
- C. Noll, M. Torrence, "ILRS Web Site Update", 16th International Workshop on Laser Ranging, Poznan, Poland, October 2008. (PDF poster | 4 Mbytes)