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 meetings page to view a list of upcoming meetings and events of interest to the space geodesy community.
ILRS survey of user tracking needs
(21 March 2017)
Many stations in the ILRS network are nearly saturated in their tracking schedule. The ILRS is presently assessing its tracking needs to try to maximize its utility. We recently sent out an email to various ILRS users and groups to ask for user needs. If you want your needs to be considered, and did not receive an email invitation, please send an email to Erricos Pavlis (epavlis @ umbc.edu). Once we compile the results, the ILRS plans to make revisions to its tracking list based on users needs. Therefore, user input is critical. The survey should not take you more than 5-10 minutes to complete, depending on your level of involvement with SLR data. Thank you for supporting the ILRS!
RINEX V3 BRDC file now availablee
(28 February 2017)
Using software supplied by the IGS Infrastructure Committee, the CDDIS is now generating a combined, concatenated broadcast ephemeris file containing unique multi-GNSS navigation messages in RINEX V3 format. The files, starting operationally in late February 2017, are named BRDC00IGS_R_yyyyddd0000_01D_MM.rnx.gz and are available on the CDDIS in the yearly BRDC directory (ftp://cddis.nasa.gov/gnss/data/daily/YYYY/brdc) and in the daily "p" subdirectories (ftp://cddis.nasa.gov/gnss/data/daily/YYYY/DDD/YYp). The file is created using the individual station "01D_MN.rnx" RINEX 3 broadcast ephemeris files using navigation messages from each satellite constellation and removes duplicate entries. The CDDIS will create older RINEX V3 BRDC files going back to 01/2016 in the near future.
CDDIS successfully moves all primary operations to an upgraded computer system
(01 December 2016)
CDDIS successfully moved all primary operations to an upgraded computer system on December 01, 2016; in total, the CDDIS archive was inaccessible to the user community for approximately 30 hours during the transition. The new IT infrastructure provides a more robust, reliable, and expandable system with increased storage capacity to handle future growth. All suppliers of data, derived products, and ancillary files for the CDDIS archive were required to modify their software to use the HTTP protocol for file upload. In addition to new hardware, the CDDIS archive processing software was redesigned and improved to provide for more efficient operations and additional QC on incoming files.
CDDIS unavailable November 30-December 01 for transition to new systems
(17 Nov 2016)
On November 30, 2016 at 13:00 UTC, CDDIS will terminate all services (ftp, CDDIS/ILRS/SGP websites, data deliveries) as we transition to all new hardware and facilities. We are projecting about 24 hours to fully move to our new facilities and ensure all operations are back to normal. As such, all users need to plan on a 24+ hour disruption of service to the CDDIS archive with resumption of normal operations no earlier than December 01, 2016 at 17:00 UTC.
In summary the following will take place:
- 30 November 2016 at 13:00 UTC – All current production services (ftp, http, etc) will be shutdown.
- 01 December 2016 at 17:00 UTC – all web and anonymous ftp access is restored for access to the archive. NOTE: restoration could occur sooner but no guarantees are made.
- Currently used addresses, e.g., cddis.nasa.gov or cddis.gsfc.nasa.gov, will continue to work as before the transition. However, if you are using a numeric IP address to access any CDDIS resources your scripts will fail as all current IP addresses will change during the transition.
- 02 December 2016 – All CDDIS operations should be returned to normal service.
While CDDIS is unavailable, users can access one of the other data centers supporting the services:
- IGS: http://www.igs.org/about/data-centers
- ILRS: http://ilrs.gsfc.nasa.gov/data_and_products/data_centers/index.html (check before November 30!)
- IVS: http://ivscc.gsfc.nasa.gov/about/org/components/dc-list.html>
- IDS: http://ids-doris.org/data-products/info.html
2016 User feedback survey (07 Sep 2016)
Beginning this week, NASA will be conducting a survey for users of NASA Earth science data and services, which includes the Crustal Dynamics Data Information System (CDDIS). The CDDIS is one of twelve NASA Earth Observing System Data and Information System (EOSDIS) science data centers evaluated by this survey. The purpose of this survey is to help NASA and the DAACs assess customer satisfaction and improve future services. Suggestions from past surveys have been implemented to improve the tools and services offered by the CDDIS.
The American Customer Satisfaction Index (ACSI) is the only national cross-industry measure of customer satisfaction in the United States. NASA commissioned the CFI Group, an independent research and consulting organization to conduct the survey. Presentations of these results given to NASA Earth science are available at: http://earthdata.nasa.gov/about-eosdis/performance/american-customer-satisfaction-index-reports.
Please participate! Your feedback affects our future performance and helps to identify science needs. You will be able to take the survey for each DAAC you use. If you use NASA Earth science data and services and would like to take the survey but did not receive an e-mail with the survey link, please contact email@example.com. This is your opportunity to influence the priorities of the DAACs. Thank you in advance to all of you who are willing to spend a few minutes to complete the survey.
Brief network outages at GSFC on September 03, 2016 (30 August 2016)
Work will be performed on the NASA GSFC network infrastructure from 09:00 a.m. EDT (13:00 UTC) through 05:00 p.m. EDT (21:00 UTC) on Saturday, September 03, 2016. Users may experience short intermittent interruptions in connectivity to CDDIS web and ftp sites during that time period.
Should the CDDIS be unaccessible, users can access one of the other data centers supporting the services:
- IGS: http://www.igs.org/about/data-centers
http://ilrs.gsfc.nasa.gov/data_and_products/data_centers/index.html (check before September 03!)
- IVS: http://ivscc.gsfc.nasa.gov/about/org/components/dc-list.html
- IDS: http://ids-doris.org/data-products/info.html
LARES + LAGEOS 1&2 Lense-Thirring results selected as EPJ-C cover (19 July 2016)
The article, "A test of general relativity using the LARES and LAGEOS satellites and a GRACE Earth gravity model," (Ciufolini et. al.) has been published in the March 2016 issue of the European Physical Journal-C. Furthermore, a figure from this paper has been selected for the cover of that issue.
The passing of Dr. Bob Coates (12 July 2016)
We are saddened to report the passing of Dr. Bob Coates, a long time colleague in the field of space geodesy. Bob was the Project Manager for NASA’s very successful Crustal Dynamics Project (CDP). Bob helped advance the SLR and VLBI technologies at NASA GSFC, incorporating them as the key measurement components of the CDP, which succeeded in describing the relative motions of the Earth’s plates with unprecedented accuracies. He will be remembered for his many contributions in both science and engineering, and for his guidance and encouragement to those who worked in the program.
NASA Space Geodesy Data for Precise Orbit Determination of Altimeter Satellites Webinar (NASA Earthdata webinar series) (29 June 2016)
Over the last 25 years, ocean radar altimeter satellites have revolutionized our understanding of the world’s oceans. Today six altimeter satellites from different national and international space agencies synoptically measure the ocean surface topography in order to determine how the ocean surface changes with time. The heart of the altimeter measurement is the precise determination of the orbit reference which is used as the basis from which the changes in the ocean surface are determined. We now routinely determine the orbits of the joint NASA/CNES/NOAA/EUMETSAT missions Jason-2 and Jason-3 with a radial RMS precision of 1 cm.
This webinar describes how we can compute these orbits with such accuracy, and will further outline how these computations rely directly and indirectly on a suite of international Space Geodesy data as well as data from different NASA satellites.
CDDIS upgrading to a new system (01 June 2016)
In the near future CDDIS will be upgrading its operations to better integrate with its parent organization, the Earth Observing System Data Information System (EOSDIS, earthdata.nasa.gov). As such there will be some significant changes taking place. The most pressing of these changes is that CDDIS will NO LONGER SUPPORT the current ftp upload procedures in our new production environment. An http/https based solution with both a command line option and web interface will be used. A test environment is now available for CDDIS data suppliers to begin their testing with our new system. Full details of how to access and use the system are provided at the URL (http://cddis.gsfc.nasa.gov/Data_and_Derived_Products/CDDIS_File_Upload_Documentation.html).
We understand that this can/will be a disruption to your operations. However, please understand that this change is necessary and we have tried to make it as painless as possible for our suppliers.
While the above URL describes the how and why, several things to keep in mind when testing are:
- This is a closed system. As you did in the past, you must provide us with an IP(s) that you will use to test as per the documentation listed above.
- The IP(s) you choose should be able to do both web-based testing and command-line testing as you will be REQUIRED to do a web-based process the very FIRST time you use the system. After that you may only use a command line if you wish.
- CDDIS will NOT process ANY data from this test bed. It is meant to be used strictly for your testing purposes in developing whatever you need to successfully upload files to CDDIS.
- All uploaded files will be removed after a short period of time.
- You must access our user registration system as defined in the documentation listed above to get a new username and password as CDDIS will be using a single sign on authentication system as well as a new automated registration system.
- We encourage feedback on your findings/suggestions. However, please use the address listed in the documentation so that it is passed on to the right departments within CDDIS. Please do NOT email Carey or Pat with technical questions; they must go to the firstname.lastname@example.org email address.
- In the next 2-3 weeks, CDDIS will provide information on testing access to the CDDIS archive in our new production environment.
- Please continue to operationally supply your files to host cddisin.gsfc.nasa.gov during this testing period.
Norway's contribution to the Global Geodetic Reference Frame (20 May 2016)
From the Norwegian Mapping Authority: Norway's contribution to the Global Geodetic Reference Frame: The Geodetic Earth Observatory in Ny-Ålesund, Svalbard. The UN General Assembly has adopted its first resolution recognising the importance of geodesy. Norway co-chaired work on the first UN resolution. Its most important contribution is the Norwegian Mapping Authority's geodetic Earth observatory in Ny-Ålesund on Svalbard. This is the northernmost facility of its kind, and plays a key role in a global network for observation and research. Data acquired here are important for climate research and monitoring.
Now 40, NASA's LAGEOS Set the Bar for Studies of Earth (04-May-2016)
On May 4, 1976, NASA launched a cannonball-shaped satellite that transformed studies of Earth’s shape, rotation and gravity field.
LAGEOS – short for Laser Geodynamic Satellite – was the first NASA orbiter dedicated to the precision measurement technique called laser ranging. With it, scientists have measured the movement of Earth’s tectonic plates, detected irregularities in the rotation of the planet, weighed it, and tracked small shifts in its center of mass.
Small deviations in the satellite’s orbit were used to develop early models of Earth’s gravitational field. Further perturbations in the orbit helped explain how sunlight heating small objects can affect their orbits, including near-Earth asteroids.
NASA Station Leads Way for Improved Measurements of Earth Orientation, Shape (10-Mar-2016)
NASA has demonstrated the success of advanced technology for making precise measurements of Earth’s orientation and rotation – information that helps provide a foundation for navigation of all space missions and for geophysical studies of our planet.
The technology includes a new class of radio antenna and electronics that provide broadband capabilities for Very Long Baseline Interferometry, or VLBI. This technique is used to make precise measurements of Earth in space and time.
VLBI measurements have been conducted for decades using a worldwide network of stations that carry out coordinated observations of very distant astronomical objects called quasars. To meet the demand for more precise measurements, a new global network of stations, called the VLBI Global Observing System, or VGOS, is being rolled out to replace the legacy network.
NASA Contributes to Global Standard for Navigation, Studies of Earth (25-Feb-2016)
The surface of Earth is constantly being reshaped by earthquakes, volcanic eruptions, landslides, floods, changes in sea levels and ice sheets, and other processes. Since some of these changes amount to only millimeters per year, scientists must make very precise measurements of the landscape and ocean in space and time in order to study their evolution and help mitigate their impacts.
Read full article.
RINEX V3 GNSS Data at CDDIS (06-Jan-2016)
Starting with data from 2016, all RINEX V3 data using the RINEX V3 filenaming convention will now be made available in the operational GNSS data archives at the CDDIS:
This change has been implemented at the IGS data centers in accordance with the IGS RINEX 3 transition plan (http://bit.ly/1Md7VhU). This update to the CDDIS archive is the next logical step to continue to integrate those stations supporting the IGS MGEX and all their data files into the regular IGS structures and make accessing all RINEX data easier and more transparent for the user community. The RINEX V3.03 format documentation is available at http://bit.ly/1YaodnI.
The CDDIS will continue to archive RINEX V3 files supplied with short names (8.3 format) in the MGEX campaign directories (ftp://cddis.gsfc.nasa.gov/gnss/data/campaign/mgex). Please contact the CDDIS staff if you have any questions or problems.