National Aeronautics and Space Administration

The Draft RFP for the SGSLR Network Build has been released and can be found at https://www.fbo.gov/notices/6f8c20c871522bb73badfcc073374ab2.

The International DORIS Service (IDS) has just published in the journal "Advances in Space Research" a special collection of papers entitled "The Scientific Applications of DORIS in Space Geodesy". DORIS is one of the four fundamental techniques that contributes to the terrestrial reference frame. It is also a prime tracking technique for LEO satellites, including those that map the oceans with radar altimetry.

The eighteen papers in the special issue cover five themes:

• ITRF2014 -- the papers discuss the DORIS contribution to the new realization of the International Terrestrial Reference Frame (ITRF);
• DORIS Ultra-Stable Oscillator (USO), Jason-2;
• Precise Orbit Determination;
• DORIS System and Network;
• Intertechnique comparisons of DORIS products.

The 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.

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.

• 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
  
  

The Space Geodesy Project posted a request for proposal for the construction, deployment and commissioning of up to three Very Long Baseline Interferometer (VLBI) antennas that will be part of the new NASA Space Geodesy Network (NSGN) and the VLBI2010 Global Observing System (VGOS). Details on the solicitation can be found here: https://www.fbo.gov/spg/NASA/GSFC/OPDC20220/NNG16573944R/listing.html.

• IGS: http://www.igs.org/about/data-centers
  
• ILRS: 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
  
  

NASA Earthdata has published a user profile of Dr. Erricos Pavlis as part of their "Who uses NASA Earth science data?" series

GFZ Potsdam and the International Laser Ranging Service (ILRS) are pleased to announce that the 20th International Workshop on Laser Ranging will be held in Potsdam Germany during the week of October 09-14, 2016 at GFZ Potsdam, Telegrafenberg. The first circular has been released.

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.

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.

A positive leap second will be introduced at the end of December 2016. More information is available from the IERS.

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.

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.

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.

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