Gy. Tóth | 2024-02-29

February 2024

General Announcements

  • New Director and Deputy of GGOS Bureau of Networks and Observations

Meeting Announcement

  • GNSS IR Short course

Meetings Calendar

IAG Sponsored Meetings

  • IVS 13th General Meeting and 25th Anniversary
  • Short Course on GNSS-IR for Water Level Measurements
  • 20th Geodynamics and Earth Tides Symposium (G-ETS 2024)
  • Gravity, Geoid and Height Systems 2024
  • GGOS Days and GGOS Focus Areas Topical Meeting
  • 6th Joint International Symposium on Deformation Monitoring (JISDM)
  • IAG Scientific Assembly 2025

Geodesy Related Meetings

  • EGU General Assembly 2024
  • ION Pacific PNT Conference
  • FIG Working Week 2024
  • Japan Geoscience Union Meeting 2024
  • 34th Conference on Mathematical Geophysics
  • 18th Symposium of SEDI
  • 45th COSPAR Scientific Assembly
  • 32th IAU General Assembly
  • 2024 European Polar Science Week conference


  • AQG operator meeting 2024: workshop and joint measurements

General Announcements

New Director and Deputy of GGOS Bureau of Networks and Observations

We are pleased to announce that our colleagues

  • José Rodriguez – from the Red de Infraestructuras Geodésicas RIG, Instituto Geográfico Nacional IGN, Spain
  • and Martin Lidberg from Lantmäteriet, the Swedish Mapping, Cadastral and Land Registration Authority,

have taken over the coordination of the GGOS BNO (Bureau of Networks and Observations) as Director and Deputy Director respectively. Their professional expertise guarantees a successful contribution to the further development of GGOS. We warmly welcome José and Martin and greatly appreciate their support.

We do not want to end this message without paying tribute to Mike Pearlman for all his efforts and successes over the past years at the helm of the BNO. We also thank him for his willingness to continue as a member of the BNO and to assist José and Martín in the transition.

Kind regards
Laura Sánchez, GGOS President
Martin Sehnal, Director of the GGOS Coordinating Office

Meeting Announcement

GNSS IR Short Course

The GNSS Interferometric Reflectometry (GNSS-IR) Community is happy to announce that we will be holding a virtual short course on March 6/7. The first two-hour session will be dedicated to the basic principles of GNSS-IR, while the second two hour session will cover theory and applications of GNSS-IR for measuring water levels in rivers, lakes, and the ocean. Examples using both geodetic-quality and low-cost sensors will be shown.

A main goal of the course is to teach people how to use the gnssrefl software, an open source software package in python for GNSS-IR applications:

Further details about the short class - including how to register - will be posted at the following link in mid-February:

This short course is being sponsored by the Collaborative Research Center 1502 DETECT, Bonn University.

Makan A. Karegar

Meetings Calendar

IAG Sponsored Meetings

Geodesy Related Meetings

Further details are available in the IAG Event Calendar at:


AQG operator meeting 2024: workshop and joint measurements

Organized by the GFZ Section 4.4 “Hydrology” and under the umbrella of the Collaborative Research Centre “TerraQ” (SFB 1464), the world's first workshop on the “Absolute Quantum Gravimeter” (AQG, Exail) took place from 22 to 26 of January 2024 at Leibniz University Hanover (Germany), together with a joint measurement session from several AQG instruments. It was the first meeting of the community of quantum gravimeter operators after this instrument became available as the first commercially new type of absolute gravimeter. The AQG is a gravimeter which uses quantum technology of free falling, cooled atom clouds for measuring the acceleration due to the attraction of the Earth and related masses.

International workshop with lively exchange

Credit: Przemysław Dykowski
The two-day workshop (24 to 25 of January) was attended by more than 30 participants from 14 organizations and 7 different countries, including the instrument manufacturer (Exail). First experiences with the instrument were exchanged and theoretical questions related to the measurement principles, instrument development, open questions and future standards were discussed. The main aim of the workshop was to initiate a continuous exchange within the AQG community and to establish a user platform from which all current and future AQG operators could benefit.

Besides the traditional field for gravimetry, geodesy, the AQG community and its end-users were spread within applied geoscience in e.g. hydrology and vulcanology. Engaging and extensive discussions in an open and welcoming atmosphere contributed to the success of the event.

First comparative measurements at the same location

Along the workshop, measurements with AQGs were carried out for a week in a gravimetric laboratory at Leibniz University Hanover. A gravimetric laboratory is characterized by very stable foundation structures on which the devices are placed and also offers constant conditions in terms of room temperature and humidity. The aim is to minimize possible interference factors on the measurements.

Credit: Przemysław Dykowski
Five AQG units of the same type (version B) came together in one room for the first time anywhere in the world. The following teams participated in the measurements: instrumental park of Action Spécifique Gravimétrie of Epos-France (AQG-B01), the German Research Center for Geosciences in Potsdam (AQG-B02), the Institute of Geodesy and Cartography, Poland (AQG-B07), the Leibniz Institute of Applied Geophysics in Hanover (AQG-B09), and the German Federal Agency for Geodesy and Cartography in Leipzig (AQG-B10). The measurement activities were spread within 5 days (day and night) and included a series of test measurements aimed at deepening the knowledge of the functioning of AQG gravimeters produced by Exail. This non-official comparison did not have the focus on obtaining the most precise absolute gravity station values but the joint measurements were carried out with the intention of testing certain device characteristics and behaviors, with the focus on comparing the performance of the devices. Among other things, this involved the noise behavior of the devices and their stability during longer measurements. Repeatability, i.e. how accurately a result can be measured again at the same point, was also a central point of the comparison.

Pushing forward IAG activities

The entire meeting (workshop and measurements) is well aligned with the goals of two groups within the IAG: The WG Q.1: “Quantum gravimetry in space and on ground” of the IAG Project – Novel Sensors and Quantum Technology for Geodesy (QuGe) as well as Sub-Commision 2.1. “Terrestrial gravimetry for the needs of geosciences and metrology”. Both groups emphasize the importance of stimulating communication, cooperation and knowledge dissemination through international meetings and workshops.

Marvin Reich – Vice-Chair WG Q.1: “Quantum gravimetry in space and on ground”(term 2023-2027)
Przemysław Dykowski – Chair Sub-Commision 2.1. “Terrestrial gravimetry for the needs of geosciences and metrology” (term 2023-2027)

The IAG Newsletter is under the editorial responsibility of the Communication and Outreach Branch (COB) of the IAG. It is an open forum and contributors are welcome to send material (preferably in electronic form) to the IAG COB ( These contributions should complement information sent by IAG officials or by IAG symposia organizers (reports and announcements). The IAG Newsletter is published monthly. It is available in different formats from the IAG new internet site:

Each IAG Newsletter includes several of the following topics:

  1. news from the Bureau Members   
  2. general information
  3. reports of IAG symposia
  4. reports by commissions, special commissions or study groups
  5. symposia announcements
  6. book reviews
  7. fast bibliography

IAG Events