This page contains all recent ILRS news. For those interested in news specific to satellite missions, please visit our Mission News page.
Paper regarding estimation of systematic errors in LAGEOS observations 1993–2014 publishedRelease Date: 07/25/2016A paper by Graham Appleby, José Rodríguez, and Zuheir Altamimi, titled, "Assessment of the accuracy of global geodetic satellite laser ranging observations and estimated impact on ITRF scale: estimation of systematic errors in LAGEOS observations 1993–2014," has been published in the August, 2016 issue of the Journal of Geodesy. doi:10.1007/s00190-016-0929-2.
First Circular for the 20th International Workshop on Laser Ranging ReleasedRelease Date: 07/19/2016
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.
LARES + LAGEOS 1&2 Lense-Thirring results selected as EPJ-C coverRelease Date: 07/19/2016
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 CoatesRelease Date: 07/12/2016
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.
Positive leap second to be introducedRelease Date: 07/11/2016
A positive leap second will be introduced at the end of December 2016. More information is available from the IERS.
NASA Space Geodesy Data for Precise Orbit Determination of Altimeter Satellites Webinar (NASA Earthdata webinar series)Release Date: 06/29/2016
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.
ILRS Networks and Engineering SC ForumRelease Date: 06/15/2016
The ILRS Networks and Engineering Standing Committee (NESC) has created an online forum to allow colleagues to discuss issues, develop ideas, pose questions, and ask for or provide advice. Although the forum was created within the NESC, membership is open to the ILRS community in general. The forum is accessible at: http://sgf.rgo.ac.uk/forumNESC/.
Norway's contribution to the Global Geodetic Reference FrameRelease Date: 05/23/2016
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 EarthRelease Date: 05/04/2016
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.
The GREAT experimentRelease Date: 04/27/2016
The unplanned eccentric orbit of Galileo-201 and -202 provides a unique opportunity to study the behavior of on-board clocks and the gravitational redshift predicted by General Relativity. The Galileo-201 and -202 satellites, the first two Fully Operational Capability (FOC) satellites, were launched on August 22, 2014. Due to technical problems with the launch, these satellites remain in an elliptical orbit, which is not useful for the Galileo operations.
Colleagues with the Galileo mission have proposed a one-year, ESA funded experiment, GREAT (Galileo gravitational Redshift Experiment with eccentric sATellites) during which the SLR will provide periods of intensive tracking on Galileo-201. The GREAT experiment will begin May 1, 2016. The stations in the ILRS network are asked to support this experiment.
The 20th International Workshop on Laser RangingRelease Date: 03/22/2016
The 20th International Workshop on Laser Ranging will be held at the Helmholtz Centre Potsdam/GFZ German Research Centre for Geosciences in Potsdam Germany on October 09-14, 2016. More information, including registration and abstraction submission deadlines, is available on the workshop’s website: http://iwslr2016.gfz-potsdam.de/international-workshop-on-laser-ranging/
Happy Birthday Vladimir Vasiliev!Release Date: 03/21/2016
The ILRS sends warmest wishes to our colleague Prof. Vladimir Vasiliev who celebrated his 85th birthday on March 18, 2016. He continues to actively contribute to various space projects, including those of interest to the ILRS. Prof. Vasiliev is a Doctor of Technical Science and Chief Research Scientist at JC «RPC «PSI». He is also the author of 5 monographs and more than 250 scientific papers. Happy Birthday Vladimir!
NASA Station Leads Way for Improved Measurements of Earth Orientation, ShapeRelease Date: 03/10/2016
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.
New version of the ILRS Mission Support Request form released Release Date: 03/09/2016
Under the direction of the ILRS Missions Standing Committee (Toshi Otsubo and Scott Wetzel) and the ILRS Central Bureau, a new version of the ILRS Mission Support Request form has been formulated and posted on the ILRS website:
This new form, available in Adobe PDF forms format, provides an improved method for obtaining the information required by the ILRS to support future missions. The form is easier to fill out and read; some additional questions have been added while obsolete, previously requested information has been removed. We encourage our mission colleagues to take a look at the new form and use it the next time support for a new mission is required!
Thanks to Toshi, Scott, the MSC, and the ILRS CB for their work on and reviews of the new MSR form.
The passing of Carroll AlleyRelease Date: 03/02/2016
The ILRS is sad to report that Carroll Alley, Professor Emeritus of physics at the University of Maryland College Park passed away on February 24, 2016. Dr. Alley was the Principal Investigator for the Lunar Laser Ranging Retroreflector experiment placed on the Moon in 1969 by the crew of Apollo 11. More information can be found at:
http://www.legacy.com/obituaries/name/carroll-alley-obituary?pid=1000000177892088. Carroll was a person of great vision and strength to the scientific community.
NASA Contributes to Global Standard for Navigation, Studies of EarthRelease Date: 02/25/2016
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.
Working Groups now called "Standing Committees"Release Date: 02/24/2016
The IAG, which is the parent organization of the ILRS, has informed the ILRS that we can no longer use the term "Working Group" for our entities that have a lifetime longer than four years. Therefore, ILRS "Working Groups" (Analysis, Networks and Engineering, Data Formats and Procedures, Missions, and Transponders) will now be called "Standing Committees". Over time, high-level documentation and web material will be changed to reflect the new terminology, as must all new material being produced within the ILRS.
Satellite Laser Ranging Research Geophysicist Position at NASA/GSFCRelease Date: 01/13/2016
The Sciences & Exploration Directorate, Solar System Exploration Division, Laser Remote Sensing Laboratory (Code 694) at NASA Goddard Space Flight Center is seeking a research scientist to provide expertise in space geodesy and Satellite Laser Ranging (SLR) system development and operations. As a Research Geophysicist, the successful candidate will be responsible for conducting, managing, planning, and directing the research and development of NASA’s next generation SLR stations. Conceives and conducts instrument and systems development to increase fundamental knowledge and understanding of space geodesy via SLR. Serve as a technical leader for the implementation of new NASA SLR stations as part of the NASA Space Geodesy Network (NSGN), and ensure the operational NSGN produces the data required by NASA missions and the scientific community. Identify problems and requirements for making geodetic SLR observations to best achieve an improved understanding of Earth dynamic processes, and initiating new experiments and programs to address these problems. Responsible for the development of new and novel applications of the SLR technique. Participate in the writing and publication of significant scientific and technological findings in appropriate journals and other media. Give presentations at scientific and technical meetings, both nationally and internationally. Responsible for defining, articulating, advancing, and publicizing NASA's role in the worldwide SLR community and participating in the direction of international organizations using SLR results and supporting SLR activities. This includes leading and supporting activities of the International Satellite Laser Ranging Service (ILRS). Work closely with NASA and NASA partner mission owners to develop SLR related requirements on the mission, associated retroreflectors, and the operational SLR network to meet the mission's science requirements. Applicants should have experience in instrument design, research and development of precision laser ranging and related optical measurement systems (such as SLR, LIDAR, and laser interferometers) and their application to space geodesy, geoscience, and/or Earth observations. Further information about NASA’s Space Geodesy Project can be found at: http://space-geodesy.nasa.gov.
U.S. citizenship is required. To view the full vacancy announcement, which contains further information including qualification requirements and application instructions, go to (http://www.usajobs.gov/GetJob/ViewDetails/426383000). Applications must be received by February 29, 2016 via the USAJobs website. For additional questions, please contact Dr. Stephen M. Merkowitz at firstname.lastname@example.org.
NASA GSFC is an Equal Opportunity Employer.
Changes in NORAD and COSPAR IDs for COMPASS satellitesRelease Date: 01/06/2016 The COSPAR and NORAD numbers in the CPF files for Compass-MS1 and Compass-MS2 were incorrect (they did not correspond to the TLE data); the numbers were switched by the prediction provider starting with CPF 5041 (dated January 05, 2016) and now correspond to the TLE data. The SIC numbers did NOT change. The ILRS website has been updated as well.
- Compass-MS1: NORAD ID=40749/COSPAR ID=1503702/SIC=2007
- Compass-MS2: NORAD ID=40748/COSPAR ID=1503701/SIC=2008
Data archived before the change will be replaced at the data centers shortly.