• Laser ranging to the moon
    Laser Ranging to the Moon
    NGSLR, located at NASA GSFC's Goddard Geophysical and Astronomical
    Observatory (GGAO),is shown ranging to the Lunar Reconnaissance Orbiter (LRO)
    orbiting the Moon. The LRO Laser Ranging (LR) system enables the spacecraft
    to achieve its precision orbit determination requirement.
  • antenna
    GGAO VGOS
    VGOS, located at NASA GSFC's Goddard
    Geophysical and Astronomical Observatory
    (GGAO), is the next generation of
    geodetic VLBI systems currently
    under development.
  • Monument brace
    Drilled Brace Monument for GNSS Antenna
    The newly installed drilled brace monument for the
    Global Navigation Satellite System (GNSS) antenna at
    NASA GSFC's Goddard Geophysical and Astronomical
    Observatory (GGAO). The multi-GNSS-capable
    receiver will track signals from several GNSS including
    GPS, GLONASS, and Galileo.
  • DORIS
    DORIS Antenna
    The Doppler Orbitography and Radio-positioning Integrated
    by Satellite (DORIS) antenna located at NASA GSFC's Goddard
    Geophysical and Astronomical Observatory (GGAO) tracks
    satellites equipped with DORIS beacons; NGSLR can be seen
    in the background.

Latest Project news

First year of Apache Point Lunar Laser Ranging data released under NASA stewardship
02/11/2022
Apache Point Laser ranging stationIn 2021, the Apache Point Lunar Laser Ranging station became part of the NASA Space Geodesy Network with New Mexico State University responsible for the on-site day-to-day operations and maintenance of the system. Over the past year, the NASA team worked with the former APOLLO team to establish best practices regarding observation and reduction of raw data into normal points, including the development of a new quality control process to identify centimeter-level biases in lunar laser ranging data. The new process helps to eliminate erroneous normal points and systematic biases prior to data publication. NASA Postdoctoral Fellow Nicholas Colmenares (one of the primary members of the former APOLLO group) led the development of the data procedures and archival of the data in the new version 2 of the Consolidated Range Data (CRD) format. The full set of 2021 data is now available from the Crustal Dynamics Data Information System (CDDIS) at https://cddis.nasa.gov/Data_and_Derived_Products/SLR/Lunar_laser_ranging_data.html.

The passing of Professor George Veis
01/31/2022
George VeisIt is with great sadness that we convey the passing of George Veis, scientist, teacher, and a good friend to all of us; truly one of the fathers of Space Geodesy. George continued to be endlessly creative, engaging, seducing, elegant, modern and forever young scientist, who shared his ideas with enthusiasm, and helped everyone with whom he had contact. He was a part of space geodesy from its birth, through its evolution from many meters to mm's, and he continued to think about its future until his death. He had celebrated his 92nd birthday last September 8, 2021.

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The passing of Thomas Clark
10/05/2021
Tom ClarkSpace Geodesy lost a longtime colleague and friend with the passing of Thomas Arvid Clark on September 28, 2021. Tom was a pioneer in Space Geodesy and Very Long Baseline Interferometry (VLBI), and a founding member of the NASA Crustal Dynamics Project.

Tom received his B.S. in Engineering Physics and his Ph.D. in Astro-Geophysics from the University of Colorado in 1961 and 1967 respectively. From 1966 to 1968, he served as Chief of the Astronomy Branch at NASA Marshall Space Flight Center and as Project Scientist on the Spacelab Coronagraph. At GSFC, where he moved in 1968, Tom received numerous NASA awards for his pioneering work on Radio Astronomy Explorer 1 and 2 and several generations of Very Long Baseline Interferometry systems. Tom developed the Totally Accurate Clock (TAC), an inexpensive GPS timing receiver that found widespread use in a number of global networks. Tom was named a Fellow of the American Geophysical Union (AGU) in 1991 and a Fellow of the International Association of Geodesy (IAG) in 1999. Tom was also a pioneer in amateur and digital radio; he designed and flew several low cost satellites for relaying amateur radio messages around the globe and is a past president of AMSAT. He was one of only 50 initial inductees into the CQ Amateur Radio Hall of Fame, a list which included such engineering luminaries and inventors as Guglielmo Marconi (radio), Samuel Morse (telegraph), Nikola Tesla (HF generators and radio), and John Bardeen and William Schockley (transistor). Tom retired from GSFC in 2001 but remained active in Amateur Radio activities.

Those of us who worked with Tom during the Crustal Dynamics period remember him as a brilliant mind, a very interesting and sometimes caustic character, but someone who was kind, supportive, and very helpful to those of us around him. We will miss him.

ILRS Virtual World Tour 2021 third circular released
09/30/2021
ILRS logoDear Colleagues:

We look forward to seeing you at "ILRS Virtual World Tour 2021". Progress has been made at the five tour hosts and by the session chairs. Now we have just opened the registration form. Please visit the event website below and find the link.
https://ilrs.gsfc.nasa.gov/ILRS_Virtual_World_Tour_2021/index.html
Registration period: October 1 to 15, 2021

Participants are encouraged to register as a group if possible, due to the limit of Microsoft Teams individual participants allowed. The URL links will be sent only to the registered people.

See you in a month!

ILRS Virtual World Tour 2021 Organizers:
Claudia Carabajal/SSAI, Inc, NASA Goddard Space Flight Center, USA
Evan Hoffman/NASA Goddard Space Flight Center, USA
Igor Ignatenko/VNIIFTRI, Russia
Jason Laing/Peraton NSGN Operations Lead, USA
Toshimichi Otsubo/Hitotsubashi University, Japan (Chair)
Michael Pearlman/ Harvard-Smithsonian Center for Astrophysics, USA
Ulrich Schreiber/Geodetic Observatory Wettzell, Germany
Zhang Zhongping/Shanghai Astronomical Observatory, China



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