News & Events

Change of Director at Zimmerwald

February 1, 2025
As of February the 1st, Prof. Dr. Lucia Kleint will become the new Director of the Swiss Optical Ground Station and Geodynamics Observatory in Zimmerwald. We wish her all the best for this important role and would like to thank her predecessor - Prof. Dr. Thomas Schildknecht - for his 15 years of service at Zimmerwald.

Prof. Dr. Adrian Jäggi new Chair of IERS Directing Board

January 6, 2025
The primary objectives of the International Earth Rotation and Reference Systems Service (IERS) are to serve the astronomical, geodetic and geophysical communities by providing the International Celestial Reference System (ICRS) and its realization, the International Celestial Reference Frame (ICRF); the International Terrestrial Reference System (ITRS) and its realization, the International Terrestrial Reference Frame (ITRF); the Earth orientation parameters required to study earth orientation variations and to transform between the ICRF and the ITRF; geophysical data to interpret time/space variations in the ICRF, ITRF or earth orientation parameters, and model such variations; Standards, constants and models (i.e., conventions) encouraging international adherence. As of January 2025 the IERS Directing Board is chaired by A. Jäggi from the AIUB.

AIUB @ AGU24

December 13, 2024
Hosting more than 25,000 participants, the annual meeting of the American Geophysical Union (AGU) is the largest conference in the field of earth and space sciences. The AIUB contributed to AGU24 with 4 posters and 1 talk and a session entitled “Precise Orbit Determination and the International GNSS Service: Essential Disciplines and Institutions for Earth Science and Applications”. As a special highlight, the session organized by AIUB under the conference motto “What's Next for Science” presented poster contributions from almost all of the available software packages used for the evaluation of space geodetic data - such as the Bernese GNSS software developed here at AIUB - this session reviewed the status of the various combined analysis tools as they will be required for the planned ESA mission "Genesis" in the years to come.

Thomas Schildknecht receives the TS Kelso Award

November 27, 2024
Prof. Dr. Thomas Schildknecht has been announced as the recipient of the 2024 T.S. Kelso award by the Space Data Association. Having served the community for over 30 years, Thomas is a leading expert in space debris, space safety and space sustainability.

Scientific and Fundamental Aspects of GNSS

September 30, 2024
The “International Colloquium on Scientific and Fundamental Aspects of GNSS” organized by the European Space Agency (ESA) took place from 25 to 27 September in Warsaw, Poland. The AIUB contributed to the colloquium with two lectures, a poster and participation on the organizing committee. With his presentation “Genesis orbit and geodetic parameter estimation based on GNSS: Impact of transmit antenna phase pattern errors” Daniel Arnold received the Best Presentation Award. Alexandra Miller was awarded the Best Presentation Award for her poster “Impact of non-gravitational force model deficiencies for Genesis orbit and geodetic parameter estimation based on GNSS”.

Congratulations Dr. Calero

September 16, 2024
We congratulate Dr. des. Emilio Claero on the successful defence of his PhD Thesis "Determination of geodynamical properties of the Earth using undifferenced GNSS network solutions" which was supervised by Rolf Dach (AIUB), Arturo Villiger (swisstopo) und Adrian Jäggi (AIUB). We wish him all the best for the future.

Prof. Dr. Adrian Jäggi new Chair of COSPAR PSD

September 11, 2024
The aim of the Technical Panel on Satellite Dynamics (PSD) of the Committee on Space Research (COSPAR) is to support and coordinate all activities aimed at the detailed description of the motion of artificial celestial bodies. The COSPAR Bureau confirmed A. Jäggi on 11 September as the new Chair of the COSPAR PSD.

IGS Symposium & Workshop

July 8, 2024
The Astronomical Institute of the University of Bern hosted the Symposium and Workshop of the International GNSS Service (IGS) with 230 attendees from 37 countries.

Strongest Space Weather event in many years

May 18, 2024
The Sun has been particularly active in May 2024, producing some extremely large eruptions and thus enhanced space weather. The eruptions expelled charged particles in the direction of Earth where they arrived on May 10, causing one of the largest displays of aurora in decades, or possibly even centuries. This event is highly interesting for our research. (Image credit: NASA/SDO, helioviewer.org)

AIUB at EGU

May 1, 2024
As in previous years, the AIUB sent a strong delegation to Vienna for the EGU24. The General Assembly of the European Geosciences Union brought together more than 18,000 earth scientists from all over the world. AIUB contributed 4 lectures, 4 posters and the organization of the session "Precise Orbit Determination for Geodesy and Earth Science" and the co-organization of the session "Satellite Gravimetry: Data Analysis, Results and Future Mission Concepts". The EGU offers our scientists an excellent opportunity to meet with other researchers and develop new opportunities for work at AIUB.

Congratulations Dr. Desprats

April 1, 2024
We would like to congratulate Dr. des. William Desprats on the successful defence of his PhD thesis here at the Exakte Wissenschaft building on the 8th March 2024. His thesis “Simulation Study for Geodetic Parameter Recovery at Europa and Callisto” was supervised by Daniel Arnold (AIUB) and Stefano Bertone (INAF, Astrophysical Observatory of Torino, Italy &
University of Maryland, College Park, USA), Michel Blanc (IRAP, CNRS-Université Paul Sabatier, Toulouse, France) and Adrian Jäggi (AIUB).

SERI-funded ERC Consolidator Grant for Prof. Dr. Lucia Kleint

December 22, 2023
Prof. Dr. Lucia Kleint has received one of the highly coveted and competitive ERC Consolidator Grants 2022, which starts on January 1, 2024 and is now funded by the State Secretariat for Education, Research and Innovation (SERI) (Staatssekretariat für Bildung, Forschung und Innovation SBFI). This grant will also be used to build a new instrument for the observatory in Zimmerwald, which will be used to study eruptions on the sun and stars.
In an article in uniAKTUELL and a video Prof. Kleint explains, among other things, why the conditions for her research at the University of Bern are so ideal, what she advises young female scientists and what she does with the funding.

ESA Technology image of the week

November 23, 2023
An ESA project with the Astronomical Institute of the University of Bern (AIUB) investigated the tumbling behaviour of derelict satellites. The study was supported through ESA’s General Support Technology Programme, developing promising technologies for space. The project combined optical, laser ranging and radar observations to refine an existing ‘In-Orbit Tumbling Analysis’ computer model, aiming to identify, understand and predict the attitude motion of a fully defunct satellite within a few passes. More than 20 objects were observed during a two-year campaign. Among the study results, it was found that rocket bodies and satellites in lower orbits are mostly influenced by gravity gradients and magnetic-induced eddy currents, while up at geostationary altitudes, satellites with large solar panels are sensitive to solar radiation pressure.

21st Swiss Geoscience Meeting

November 18, 2023
The 21st Swiss Geoscience Meeting (SGM) was held on 17 – 18 November in Mendrisio, Ticino. With a series of 26 scientific symposia taking place on 18 November the broad spectrum of activities, societies and commissions within the Platform Geosciences of the Swiss Academy of Sciences (SCNAT) was reflected. For the first time also the Swiss Geodetic Commission (SGC) organized a symposium at the SGM which was uniquely devoted to geodesy. With a total of 20 oral presentations the session no. 22 “Geodesy” provided a broad overview of the various geodetic activities on-going at the different institutions in Switzerland. The Astronomical Institute of the University of Bern (AIUB) contributed to the SGM with the symposium organization and a total of six presentations.

Co-Organization of ISSI Workshop

November 13, 2023
The Astronomical Institute of the University of Bern (AIUB) co-organized the workshop “Remote Sensing In Climatology – Essential Climate Variables (ECVs) and their Uncertainties” taking place at the International Space Science Institute (ISSI) in Bern from 13 - 17 November 2023. The central research questions addressed at the workshop were, among others, the quantification of systematic and stochastic uncertainties and errors in Earth Observation time series data and the effect on climate change detection from ECVs. The workshop was attended by 45 invited scientists and experts and shall lead to a volume of the Space Science Series of ISSI and in parallel to an issue of papers to be published in Surveys in Geophysics.

Precise orbit determination of Spire CubeSats

October 31, 2023
The company Spire Global Inc. operates an entire fleet of nano satellites with on board dual-frequency GNSS receivers. In the frame of an ESA Announcement of Opportunity, AIUB obtained exclusive data access and could successfully employ it for computing the satellite orbits with a cm accuracy. This is a first crucial step towards exploiting data of megaconstellations for scientific applications, like gravity field determination.

Prof. Dr. Adrian Jäggi appointed to two ESA committees

October 23, 2023
Prof. Dr. Adrian Jäggi was appointed in 2023 to the Global Navigation Satellite System (GNSS) Science Advisory Committee (GSAC) of the European Space Agency ESA. GSAC is the senior advisory body to the Director of Navigation (D/NAV) and the Director of Science (D/SCI), acting as the ESA Director General's representatives, on all matters concerning scientific exploitation of navigation programmes.
Prof. Dr. Adrian Jäggi was appointed in 2023 in addition also to ESA’s Next Generation Gravity Mission (NGGM) Mission Advisory Group (MAG). The objective of the MAG is to advise ESA on the Next Generation Gravity Mission of Opportunity (NGGM) as part of ESA’s FutureEO Programmes.

Reprocessing of GOCE data

September 11, 2023
The ESA mission GOCE measured the Earth's static gravity field with unprecedented spatial resolution. Even though the mission was accomplished already in 2013, a meanwhile completed reprocessing of the entire set of GOCE data enabled the generation of still significantly better gravity field models. The AIUB was responsible for the recomputation and improvement of the GOCE satellite orbits.

COST-G Fitted Signal Models featured on ESA Sentinel Online

August 3, 2023
The Copernicus Precise Orbital Determination (CPOD) service reports on ESA’s Sentinel Online portal about the improved accuracy of the service’s outputs by incorporating the COST-G Fitted Signal Model, computed at the Astronomical institute of the University of Bern (AIUB), into its data processing procedures. When compared to CPOD’s previous gravity field model, the new COST-G model results in improvements in all observed precise orbit determination metrics, including reduction of GNSS carrier phase residuals, improvement in orbital comparisons between the CPOD quality working group solutions, and reduction of empirical signals.

The AIUB at the IUGG 2023 in Berlin

July 21, 2023
Under the motto "Together Again for Geosciences", the International Association of Geodesy (IAG), as one of the eight Associations of the International Union of Geodesy and Geophysics (IUGG), contributed to the 28th General Assembly of IUGG in Berlin, Germany, from July 11-20, 2023. Prof. Dr. Adrian Jäggi of the Astronomical Institute of the University of Bern (AIUB) was also present in his capacity as President of IAG Commission 2 (Gravity Field) together with eight AIUB collaborators and one student volunteer.

Prof. Dr. Lucia Kleint new president of the Swiss SCOSTEP

January 31, 2023
Since January 2023, Prof. Dr. Lucia Kleint, head of the research group “Space Weather” at the Astronomical Institute of the University of Bern (AIUB), is the new president of the Swiss National Committee of the Scientific Committee on Solar Terrestrial Physics (NC SCOSTEP, www.scostep.ch). SCOSTEP is a commission of the Swiss Academy of Sciences (SCNAT).

G3P project at AIUB successfully completed

March 15, 2023
After three years, the Global Gravity-based Groundwater Product (G3P) project has successfully ended with the publication of the global Groundwater Storage Anomaly (GWSA) maps developed by the project team. The Astronomical Institute of the University of Bern (AIUB) led work package 2 of the G3P project, which aimed at providing global maps of the "Terrestrial Water Storage" (TWS). The G3P project was funded by the EU Horizon 2020 grant program on "Copernicus evolution - Research activities in support of cross-cutting applications between Copernicus services" under grant no. 870353.

New Professor

February 1, 2024
The institute is pleased to announce the promotion of Lucia Kleint to the post of Associate Professor (ausserordentliche Professorin) on the 1st of February 2024. The appointment reflects the success of Lucia and her Space Weather Group and we look forward to the many fruitful collaborations her work will bring with the existing groups at AIUB – congratulations Lucia!

For more information, please see the official communication of the University linked below.

Prof. Dr. Adrian Jäggi new Chair of the SGC

January 2, 2023
Since January 2023, Prof. Dr. Adrian Jäggi, Director of the Astronomical Institute of the University of Bern (AIUB), is the new Chairman of the Swiss Geodetic Commission (SGC, https://www.sgc.ethz.ch/index.html), a commission of the Swiss Academy of Sciences (SCNAT, https://scnat.ch/). He replaces the previous president of the SGC, Prof. Dr. Markus Rothacher. Adrian Jäggi thus joins a long tradition of close relations between AIUB and the SGC.

Double Anniversary: 100 Years Astronomical Institute - 200 Years Uraniae

In November 2022, the Astronomical Institute of the University of Bern (AIUB) celebrated a double anniversary: 200 years Uraniae and 100 years Astronomical Institute. On Friday, November 25 and Saturday, November 26, 2022, the double anniversary was celebrated with a ceremony, a scientific symposium, and exciting ctivities for the general public at the University of Bern. In addition, a commemorative publication (Festschrift) is available.

New GCOS implementation plan 2022

The Global Climate Observing System (GCOS) published the new GCOS implementation plan 2022. For the first time it includes Terrestrial Water Storage (TWS) as a new Essential Climate Variable (ECV). Total terrestrial water storage (TWS) comprises all the water storage on the Earth’s continental areas in frozen and liquid state. Satellite observations of the Earth's time-variable gravity field such as from GRACE (2002-2017) and GRACE Follow-On (launched in 2018) provide global-scale information on mass changes on and below the Earth surface. Gravity data thus provide the basis to observe the new ECV.

New research group at AIUB

9. August 2022:
In July 2022, a new research group was established at the Astronomical Institute of the University of Bern (AIUB). Prof. Dr. Lucia Kleint leads the space weather group, formerly located at the University of Geneva. As the vice-director of the Zimmerwald observatory, Prof. Kleint leads its daily operations with the goal of determining orbits of various satellites and investigating space debris.

11. Copernicus POD QWG Meeting in Bern

8. August 2022:
On June 21-23, 2022, the 11th meeting of the Copernicus Precise Orbit Determination Quality Working Group took place at the University of Bern. Copernicus, the European Union's Earth observation program, is based on satellite measurements of the Sentinel fleet and other satellite missions. The purpose of the Quality Working Group is to ensure a high quality of the computed satellite orbits and to continuously improve them.

Meeting of the COST-G Consortium

11. July 2022:
COST-G stands for „Combination Service for Time-Variable Gravity Fields” and is part of the „International Gravity Field Service” (IGFS) of the „International Association of Geodesy” (IAG). Representatives of the COST-G team met on July 4 – 7, 2022 under the lead of the Astronomical Institute of the University of Bern at the „International Space Science Institute“ (ISSI) in Bern to discuss current developments.

Rolf Dach new Vice-Chair of the IGS GB

05. July 2022
In the frame of the first virtual workshop of the International GNSS Service (IGS) Rolf Dach was elected Vice-Chair of the IGS Governing Board (GB). The GB is that panel which advises and defines the strategic orientation of the IGS. As Vice-Chair he will collaborate together with the current chair Felix Perosanz (CNES) and with Allison Craddock (chair of the Central Bureau) and thus will be able to actively form the further development of the IGS. Thereby the Astronomical Institute of the University of Bern (AIUB) is taking an important position in the IGS again.

SLR through a Slit!

29. June 2022:
On June 24, after more than 4 years of preparatory work and 4 months of construction work, the satellite laser ranging (SLR) system at the Swiss Optical Ground Station and Geodynamics Observatory Zimmerwald was equipped with a new dome. In future the laser will pass through the slit of this new dome on its journey towards satellites and back. The new dome shall reduce the thermal load on the telescope during daytime operation and thus increase the yield substantially.

Meeting of the CODE Consortium

6. april 2022:
CODE stands for „Center for Orbit Determination in Europe“ and is a Joint Venture between the Astronomical Institute of the University of Bern (AIUB), Switzerland, Federal Office of Topography swisstopo, Wabern, Switzerland, Federal Office of Cartography and Geodesy (BKG), Frankfurt am Main, Germany, and the Engineering Institute for Astronomical and Physical Geodesy at the Technical University of Munich (IAPG, TUM), Germany. The four institutions are working together in different fields of satellite geodesy. Most prominent is the performance as Analysis Center of the International GNSS Service (IGS, GNSS stands for Global Navigation Satellite System). Representatives of the CODE consortium met each other on Thursday, April 5, 2022, at the University of Bern, in order to exchange about current developments and to coordinate the planning of the common future. For almost all of the participants it was the first business trip since the last meeting on March 11, 2020, in Munich.

Tour de l’IGS with Stop at AIUB

The International GNSS Service (IGS) has started in irregular order to organize virtual mini workshops on dedicated topics under the title «Tour de l’IGS». Collaborators of the Astronomical Institute of the University of Bern (AIUB) and of the CODE (Center for Orbit Determination in Europe) Consortium were significantly involved in the organization. On February 17, 2022, one of these mini workshops took place which was organized by Prof. Dr. Rolf Dach and Dr. Arturo Villiger from AIUB.

GGOS and AIUB

2. February 2022:
GGOS, the Global Geodetic Observing System, is a collaborative contribution of the global geodesy community to the observation and monitoring of the Earth System. Learn more about GGOS (https://ggos.org) and the broad variety of geodetic observations, products and services as well as the multifaceted world of geodesy and its ever-increasing benefits to science and society by clicking the link and watching the short film "Discover GGOS", to which also the AIUB contributed.

COST-G gravity field predictions for operational satellite orbit determination

10. December 2021:
Precise orbit determination (POD) of Earth observation satellites at orbit altitudes below 2000 km, so-called Low Earth Orbiters (LEOs), critically depends on the precise knowledge of the Earth’s gravity field and its variations with time. On a global scale, the time-variable gravity field is determined by the analysis of observations of the two satellites of the dedicated GRACE-FO mission (or its predecessor GRACE). In the frame of the Combination Service for Time-variable Gravity fields (COST-G) the Astronomical Institute of the University of Bern (AIUB) collects the monthly gravity field solutions of the GRACE / GRACE-FO analysis centers worldwide and derives combined solutions.

The Future is Now

15. November 2021:
Under this motto, on Friday, 05. November 2021, the day of sustainability of the three Bernese Universities took place at the vonRoll building. There were talks, workshops, and interactive information desks, where different contributions were presented by the groups of the University of Bern, the University of Applied Sciences, and the College of Education of Bern. The goal was the exchange of ideas and research works devoted to the topic “sustainability”. The Astronomical Institute of the University of Bern (AIUB) was also present with an own information desk.

AIUB in the scientific advisory board of the ITP-DLR

18. October 2021:
At the beginning of October Prof. Dr. Thomas Schildknecht of the Astronomical Institute University of Bern (AIUB) and Director of the Swiss Optical Ground Station and Geophysical Observatory was elected as member of the scientific advisory board of the Institute of Technical Physics (ITP) of the Deutsches Zentrum für Luft- und Raumfahrt (DLR). Situated at Stuttgart and Lampoldshausen, the research of this institute is focused on laser-based systems for aeronautics and space flight. It is expected that his expertise in the detection, positioning, and characterization of orbital objects as well as in the reduction of space debris by laser-based techniques will provide useful suggestions for the current and future orientation of the ITP-DLR.

BeiDou-3 Data in MGEX solution

20. September 2021:
The Bernese GNSS Software developed and maintained at the Astronomical Institute of the University of Bern (AIUB) has been enabled to support the Chinese GNSS (Global Navigation Satellite System) BeiDou 3 since spring 2021. Thanks to this update the multi-GNSS solution (MGEX) provided by the AIUB-located CODE (Center for Orbit Determination in Europe) as a contribution to the IGS (International GNSS Service) is now supporting the four operational GNSSes GPS (USA), GLONASS (Russia), Galileo (Europe), BeiDou 3 (China) along with the RNSSes (Regional Navigation Satellite Systems) QZSS (Japan) and BeiDou 2 (China). CODE's MGEX solution is, thus, offering free access to precise orbits, clock corrections, and signal calibration data of some 115 active navigation satellites to scientific, adminstrative, and commercial high-precision GNSS users.

Start of AIUB/ISSI and ISSI-Beijing Collaboration

25. August 2021:
On August 24/25, 2021, the ISSI and ISSI-Beijing International Team led by Prof. Wei Feng from the Institute of Geodesy and Geophysics of the Chinese Academy of Sciences and Prof. Adrian Jäggi from the Astronomical Institute of the University of Bern (AIUB) had its first meeting. The team supported by ISSI and ISSI-Beijng is a direct outcome of the round table COST-G Sino-European Meeting that was taking place 16.-17. January 2020 in Bern. The aim of the team members is to join their effort for gravity field modelling, especially to investigate the added contribution from China to generate established combined time-variable models to be included in the Combination Service for Time-variable Gravity Fields (COST-G). In addition, the simulation of constellation design for Chinese gravity satellites will be performed to pave the way to multi-pair gravity missions for improving our understanding of mass redistribution between the hydrosphere, cryosphere, atmosphere, and lithosphere.

Sentinel-6A: Orbit Determination using Galileo

20. August 2021:
On November 21, 2020, the satellite Sentinel-6A was launched into a low orbit. As the first Sentinel satellite it carries on board a GNSS receiver allowing it to also use the signals of the European Global Navigation Satellite System Galileo for orbit determination. The Astronomical Institute of the University of Bern (AIUB) is determining high precision orbit parameters of Sentinel-6A using GPS and Galileo within the framework of the Copernicus Precise Orbit Determination (POD) Quality Working Group.

Geodesy for a Sustainable Earth

2. July 2021:
Under the motto "Geodesy for a Sustainable Earth" the International Association for Geodesy (IAG) has held a scientific assembly with predominant online participation as a hybrid meeting in Peking from June 28 until 2 July 2, 2021. In his role as President of Commission 2 "Gravity Field", Prof. Adrian Jäggi from the Astronomical Institute of the University of Bern (AUB), together with the Vice-President of Commission 2, Prof. Mirko Reguzzoni from Politecnico di Milano, was in charge of organizing the conference’s symposia 2a "Static Gravity Field" and 2b "Time-variable Gravity Field". Both symposia together comprised overall 11 Sessions providing a comprehensive overview of the current research on the topic of Earth gravity field determination by 72 oral and 78 poster presentations. In Session 2b.1 "Analysis Methods", dealing with the methodologic relevant aspects of gravity field determination using satellite data, Prof. Jäggi was also chairing the meeting.

Repro3 – Reproccessing of 25 years of GNSS Data at CODE

24. June 2021:
The Center for Orbit Determination in Europe (CODE) affiliated at the Astronomical Institute of the University of Bern (AIUB) has reprocessed data amounting up to more than one Million single measurements of about 300 observing stations of the International GNSS Service during the year 2020 and generated with it a consistent time series. This product will be used to calculate high-precision coordinates and velocities of a global network of observing stations which will provide the stable geodetic foundation for future scientific applications.

Zimmerwald SLR station as World’s top class in week 13/2021

8. April 2021:
In calendar-week 13 of this year alone the satellite observation station in Zimmerwald of the Astronomical Institute of the University of Bern (AIUB) succeeded in measuring distances to over 700 satellites using a satellite laser ranging system. With this result it was the most successful station worldwide and was once more able to confirm and consolidate its foremost position at least of the northern hemisphere.

AIUB in the Advisory Board of BKG’s Gauss Center

11. March 2021:
The German Federal Agency for Cartography and Geodesy (BKG) has founded a virtual research center named “Gauss Center for Geodesy and GeoInformation”. The BKG will award contracts for research tasks to universities and research institutions via this center. On behalf of the BKG these institutions shall conduct diverse projects to gain new insights on different aspects within the disciplines of Geodesy and GeoInformation. The goal consists in subsequent using of the gained findings and developments of procedures and methods for operational works of the BKG. The Astronomical Institute of the University of Bern (AIUB), represented by its director Prof. Dr. Adrian Jäggi, is member of the advisory board of this center.

New AIUB – EUMETSAT – Collaboration

1. February 2021:
The Astronomical Institute of the University of Bern (AIUB) concluded a contract with the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT) to launch the
Bernese POD Scientific Service that shall be provided to the Remote Sensing and Products (RSP) Division within EUMETSAT’s Technical and Scientific Support (TSS) Department. EUMETSAT intends to apply the Bernese GNSS Software (BSW) as a baseline software for its scientific and operational activities related to precise orbit determination (POD) involving several missions such as EPS/Metop, Sentinel-3, EPS-SG, Sentinel-6/Jason-CS and other missions of opportunity. For this purpose, EUMETSAT has initiated a Scientific Service contributing to the maintenance and evolution of the BSW as required for EUMETSAT’s POD applications.

Operational combination of monthly GRACE-FO gravity field models

21. December 2020:
Since July 2019, the Astronomical Institute of the University of Bern (AIUB) operates the Combination Service for Time-Variable Gravity Fields (COST-G) of the International Association of Geodesy (IAG). COST-G first performs a quality control, analysing the signal content of the gravity fields provided by the GRACE-FO Analysis Centres (ACs), and then generates a combination. In November 2020, two years after the launch of the GRACE-FO satellites in May 2018, the combination at COST-G became operational, aiming at the combination of the monthly gravity fields derived from GRACE-Follow On (GRACE-FO) with short latency.

ILRS Virtual World Tour 2020

24. November 2020:
In place of an International Laser Ranging Station (ILRS) Workshop this November, the ILRS wanted to take the opportunity to try something different and look in detail at a selection of stations in the global network. This 'Virtual World Tour' took place online on November 2-6, 2020, virtually visiting 5 ILRS stations in 5 days, stopping among others also at Zimmerwald Observatory operated by the Astronomical Institute of the University of Bern, Switzerland.

Scale of Global Reference Frames from Galileo Data

3. November 2020:
The Center of Orbit Determination in Europe (CODE) of the Astronomical Institute of the University of Bern (AIUB) successfully demonstrated for the first time that the Global Navigation Satellite System (GNSS) could make an important and independent contribution to the determination of the scale when realizing new reference frames for the Earth thanks to the disclosure of the Galileo satellite antenna calibrations.

Callisto Geodesy

14. October 2020:
The subgroup "Orbit and Gravity Field Determination" of AIUB’s satellite geodesy group has recently initiated a new project, financed by the Swiss National Science Foundation, where the exploration of Callisto with an orbiting spacecraft is studied.

First Daylight Laser Measurements of a Space Debris Object

10. August 2020:
On June 24 2020, AIUB acquired the first ever daylight observations of a space debris object using a geodetic laser at the Swiss Optical Ground station and Geodynamics Observatory Zimmerwald. Such measurements may be essential to reduce the orbit uncertainty of space debris objects, hereby allowing spacecraft operators to identify close conjunctions and to devise and execute efficient avoidance maneuvers.

Breakup of an Atlas 5 upper stage observed

1. April 2019:

On March 26 we were informed by our Russian colleagues (Vladimir Agapov) that they discovered a breakup of the Atlas 5 upper stage 2009-047B (SSN 35816; apogee - 34708.9km, perigee – 6675.6km) on March 25, 2019, at 22:23 UTC. The following night we were successfully observing fragments from this event with 3 sensors at the Swiss Optical Ground Station and Geodynamics Observatory Zimmerwald. The attached animated gif shows a series of observations from the 0.8m ZimMAIN telescope.