NASA Forms Space Geodesy Working Group
05/30/2013 NASA has formed the Space Geodesy Working Group to perform fact-finding related to the scientific, technical, and organizational issues associated with the ongoing development of its Space Geodesy Program. The term of service for the Space Geodesy Working Group is three years. The Working Group is tasked to:
- Conduct semi-annual reviews of the Space Geodesy Program to include reviews of the Program's scientific requirements, strategies, and technical approaches; and
- Provide technical findings to NASA on its evaluations of and options for resolving program and project challenges following each semi-annual review.
Space Geodesy SLR Request for Information Released
05/02/2013 The National Aeronautics and Space Administration (NASA) Space Geodesy Project (SGP) is soliciting information to improve its understanding of the interest, capabilities, and Rough Order of Magnitude (ROM) estimates for planning the construction, deployment, and operation of the next generation Space Geodesy (SG) Satellite Laser Ranging (SLR) Stations that will be part of a new NASA’s Space Geodetic Network (SGN). NASA is considering the construction of up to ten new SLR stations that will contribute to the larger Global Geodetic Observing System (GGOS).
The first announcement of the next International Workshop
on Laser Ranging has been issued.Release Date: 04/23/2013
The 18th International Workshop on Laser Ranging is organized
so that worldwide scientists and engineers in this and related
fields can exchange their views, share opinions on the on-going
problems, and navigate the future.
The theme of this year's workshop is "Pursuing Ultimate Accuracy & Creating New Synergies." In addition to the important topic of maximizing accuracy,
this workshop is intended to enhance the potential of laser
ranging with the inclusion of activities in relevant fields.
The workshop will take place November 11-15, 2013 at the Highland Resort Hotel, Fujiyoshida, Japan. More information is available on the workshop website: http://geo.science.hit-u.ac.jp/lw18/.
Please consider your participation and reserve the week now.
The procedures for the registration (including hotel booking) and
the abstract submission will be announced in July.
Please contact the local organizing committee (Z-LW18@jaxa.jp) for additional information.
ITRF2013 Call for Participation
03/28/2013 Please be informed that the ITRF2013 Call for Participation is now released and could be retrieved at the ITRF web site, using the following link:
In addition to the solicited global solutions from the four
space geodesy techniques (to be provided by the Technique
Services), we also solicit and encourage the owners of
co-location sites to consider conducting new local tie surveys
using the most up to date survey methods. Indeed, the local
ties available at the ITRS Center for a certain number of
co-location sites are now old by 10 to 20 years. In this
respect, we would greatly appreciate the contribution of the
national mapping and space agencies investing and operating
co-location sites, which constitute the main foundation of the
ITRF. More details regarding the local tie survey are available
in the ITRF2013 CfP.
Earth Orientation Animations
03/01/2013 When you think of the Earth’s orientation, you’d probably imagine something like a globe, where it always rotates around an axis, called the spin axis, defined by the north and south poles. And while this generally makes sense, in reality, the Earth’s orientation is constantly changing very slightly, and this change can be described in three ways. Learn more about how the Earth's orientation changes by watching these animations.
NASA Beams Mona Lisa to Lunar Reconnaissance Orbiter at the Moon
01/28/2013 Laser communication and ranging experiments were successfully conducted from the satellite laser ranging (SLR) station at NASA Goddard Space Flight Center (GSFC) to the Lunar Reconnaissance Orbiter (LRO) in lunar orbit. The experiments used 4096-ary pulse position modulation (PPM) for the laser pulses during one-way LRO Laser Ranging (LR) operations. Reed-Solomon forward error correction codes were used to correct the PPM symbol errors due to atmosphere turbulence and pointing jitter. The signal fading was measured and the results were compared to the model.
The Mona Lisa Lasercom to the Moon from NGSLR demonstrates the potential of the SG Network beyond geodesy. The NASA news release was picked up by nearly all the major news outlets. Several members of the NGSLR team were co-authors of the paper which was published online in Optics Express.
Read the paper in Optics Express
Read the NASA news release
Dr. Henry Plotkin, visits NASA's Next Generation Satellite Laser Ranging (NGSLR) system12/2012
Retired NASA physicist, Dr. Henry Plotkin, visits NASA's Next Generation Satellite Laser Ranging (NGSLR) system in December 2012. As the former Head of the old Optical Systems Branch (Code 524) at NASA Goddard Space Flight Center, Dr. Plotkin led the development of the earliest NASA SLR systems. His team recorded the first laser returns from a retroreflector-equipped artificial satellite (Explorer 22B) almost 50 years ago on October 31, 1964. He is shown here with Jan McGarry in front of the NGSLR system.
View larger image
11/21/2012 The IGS and UNAVCO are sponsoring an evening reception on December 02, 2012 on behalf of the Global Geodetic Observing System (GGOS). A fun, educational, and humorous evening of short, fast-paced presentations will be given by people who are passionate about what they do. There will be plenty of appetizers and a cash bar.
Ignite GGOS 2012!
Sunday, December 2nd, at 7:00 pm
The Westin San Francisco Market Street
50 Third Street
San Francisco, California
Ignite is an O'Reilly Media concept meant to be fast-paced, creative, and outside-the-box of conventional conference presentations. Ignite GGOS promises to be a fun and light-hearted hour to stimulate your thinking with diverse visions for GGOS and beyond.
For more information, please contact:
IGS Central Bureau, Ignite Coordinator: craddock_AT_jpl.nasa.gov
International Technical Laser Workshop 2012 (ITLW-12)
The ILRS held an International Technical Laser Workshop 2012 (ITLW-12) on "Satellite, Lunar and Planetary Laser Ranging: characterizing the space segment" at the Frascati National Laboratories of the INFN-LNF, Frascati (Rome), Italy on November 5-9, 2012, in conjunction with a one-day Workshop on "ASI-INFN ETRUSCO-2 Project of Technological Development and Test of SLR Payloads for GNSS Satellites". The meeting focused on the laser ranging space segment including retroreflector arrays for Earth orbiting satellites and the moon, with special attention to the expanding role of ranging to GNSS and geosynchronous satellites. Topics also included receivers in space for time transfer experiments (T2L2), one-way ranging to lunar orbiters (LRO) and interplanetary spacecraft (MLA, MOLA), and data relay systems.
New ILRS web site released
The ILRS Central Bureau is pleased to announce the implementation of a new design for the ILRS website, http://ilrs.gsfc.nasa.gov. The redesign process has allowed for a review of the organization of the site and its contents, ensuring information is current and useful. Comments and suggestions are welcome and should be directed to the ILRS web team at email@example.com. We would like to acknowledge the efforts of the website development team (Lisa Lee, Mark Torrence, Lori Tyahla, and Carey Noll) as well as members of the Central Bureau and the ILRS community for their contributions to the site content.
Space Geodesy Request for Information
08/30/2012 The National Aeronautics and Space Administration (NASA) is soliciting information to improve its understanding of the interest, capabilities, and Rough Order of Magnitude (ROM) estimates for planning the construction, deployment, and operation of the next generation Space Geodesy (SG) stations that will be part of the upcoming NASA’s Space Geodetic Network (SGN). NASA is considering the construction of up to ten new or upgraded stations that will contribute to the larger Global Geodetic System (GGOS).
Staff Profile: Jan McGarry, Mathematician
08/16/2012 Mathematician Jan McGarry discusses the science and history of Satellite Laser Ranging (SLR), her role in developing the Next Generation Satellite Laser Ranging system, and her career at NASA's Goddard Space Flight Center.
NGSLR Optical Bench Laboratory Build Status
08/15/2012 The design and laboratory build of the new Optical Bench has been completed. Assembled at a GSFC Building 33 clean room laboratory, the new bench offers an improved optical layout, incorporates alignment lasers, and uses monitoring cameras for more efficient alignments. A beam profiler has been incorporated allowing verification of the transmit beam divergence and doubles as a means of monitoring the pointing of the laser. The new design now supports motorized optical mounts to enable automated operations. The Optical Bench was upgraded with a higher power, shorter pulse width laser for more robust daylight GPS ranging along with the use of high power coatings on the transmit optics to handle the extra energy. The original Optical Bench was designed for laser energies up to 350 microjoules while the new Optical Bench is designed to handle energies up to 3,000 microjoules. The laboratory build of the new Optical Bench allowed engineers to test the new layout and develop alignment procedures for the enhanced design. While the build was taking place in the laboratory, system development efforts were allowed to continue at the NGSLR. Completed in July, the new bench is in the process of being moved to the NGSLR. Pictures of the new bench undergoing the laboratory build are shown.
Time-lapse video of VLBI2010 Installation at GGAO
08/14/2012 Time lapse video showing the construction of the VLBI2010 antenna at NASA Goddard Geophysical and Astronomical Observatory GGAO, September 15 through October 12, 2010.
NGSLR 2012 Summer Interns
08/05/2012 SGP staff mentored eight interns during the summer of 2012.
Visit 2012 Interns page
Staff Profile: Carey Noll, Computer Scientist
08/02/2012 Computer scientist Carey Noll talks about her job as manager of the Crustal Dynamics Data Information System (CDDIS), the applications of her work for various space geodesy techniques such as GPS, and her career at NASA's Goddard Space Flight Center.
Staff Profile: Chopo Ma, Space Geodesist
07/12/2012 Space geodesist Chopo Ma explains the science of Very Long Baseline Interferometry (VLBI): using radio emissions from distant galaxies to create a precise reference frame for the Earth.
"Sizing Up Earth" for iPad
07/10/2012 Read an introduction to Space Geodesy using the NASA Visualization iPad app.
Download NASA Visualization iPad app
Staff Profile: Stephen Merkowitz, Project Manager
07/05/2012 Project manager Stephen Merkowitz talks about his work with NASA's Space Geodesy Project, including a brief overview of the four fundamental techniques of space geodesy: GPS, VLBI, SLR, and DORIS.
NASA Explains Why Clocks Will Get an Extra Second on June 30
06/29/2012 If the day seems a little longer than usual on Saturday, June 30, 2012, that's because it will be. An extra second, or "leap" second, will be added at midnight to account for the fact that it is taking Earth longer and longer to complete one full turn—a day—or, technically, a solar day.
Using Quasars to Measure the Earth: A History of VLBI
06/21/2012 VLBI, or Very Long Baseline Interferometry, is a technique that uses multiple radio telescopes to very precisely measure the Earth's orientation. It was originally invented back in the 1960s to take better pictures of quasars, but scientists soon found out that if you threw the process in reverse, you could measure how the ground beneath the telescopes moves around, how long days really are, and how the Earth wobbles on its axis as it revolves around the sun!
NGSLR Makes its First Successful Daylight Ranging to a GNSS Satellite
04/30/2012 NGSLR made its first successful daylight ranging to a GNSS satellite (GLONASS-109) on April 2, 2012 at approximately 7pm EDT, about 30 minutes before sunset. The system obtained satellite returns immediately after laser turn-on. The satellite was tracked for an hour, down below 35 degrees elevation. The pass was strong enough for real-time signal processing to find much of the signal. A second daylight GNSS pass on GLONASS-115 was obtained on April 3, 2012 at appoximately 2pm EDT.
NASA Response on Legacy Stations Submitted and Accepted
03/26/2012 The The NASA response on legacy stations submitted to the GGOS Bureau for Networks and Communication Call for Participation was recently accepted.
NASA Pinning Down "Here" Better Than Ever
02/23/2012 NASA is helping to lead an international effort to upgrade the four systems that supply crucial location information in pinpointing where "here" is.
VLBI2010 Demonstration with Full Configuration at GGAO
01/20/2012 VLBI2010 successfully conducted 4-band fringe test and emonstrated antenna aperture efficiency, feed horn sensitivity, and backend data system components meet baseline VLBI2010 requirements.
Installation of GNSS deep drilled brace monuments
The installation of GNSS deep drilled brace monuments at GGAO was completed. Multi-Constellation GNSS receivers, antennae/radomes, and supporting data collection computer have been installed at GGAO and are operating and actively collecting data. Both GNSS receivers are Delta-series units from Javad.