“Changing Northern Lands – Thawing Ground and Expanding Use” with Annett Bartsch (b geos, Austria)

Pronounced impacts of climate change are observed across the entire Arctic – ocean as well as on land – and they are expected to intensify. As permafrost thaws ground destabilizes and microbes are activated with local and global implications respectively. Soil carbon release into the atmosphere is amplified. High latitude permafrost regions are thus considered a tipping element in the Earth’s climate system. Several million people live on permafrost and the exploitation of natural resources has been continuously expanding across the Arctic for many decades. Earth Observation provides the means to monitor both, the relevant essential climate variables and the expanding land use. Specifically recent satellite missions in the framework of Copernicus offer the necessary level of detail. The presentation will provide insight into the potential of Earth Observation to reveal patterns of permafrost thaw as well as expanding direct human impact across the Arctic.

Annett Bartsch works in the fields of remote sensing, cryosphere and hydrology with focus on the Arctic. Her major interests are in observing climate change impacts on Earth from space, specifically understanding of impacts of permafrost thaw on carbon release and people. Her published works provide insight into remote sensing techniques suitable to efficiently monitor the land surface across large regions such as the Arctic, including novel applications and approaches. Annett received her MSc in Geography from FSU Jena, Germany (2000), her PhD from The University of Reading, UK (2004) and her venia docenti for ‚Applied Remote Sensing’ from Technical University Vienna, Austria (2011). She was a visiting professor at University of Salzburg and at LMU Munich. In 2017, she founded the Earth Observation company b.geos GmbH (Korneuburg/Vienna, Austria), which contributes to climate change related basic and applied research funded through ESA and Horizon 2020. It currently hosts Annett’s team of the ERC Synergy Grant project Q-Arctic. b.geos is a member of the Austrian Polar Research Institute which is a research consortium that promotes and coordinates research and education in the area of polar sciences.

Webinar was recorded on May 12, 2022 



Pro ISSI Talk: Space Debris – Providing the Scientific Foundation for Sustainable Use of Outer Space

with Thomas Schildknecht, Astronomical Institute, University of Bern, Switzerland


Abstract: The proliferation of space debris and the increased probability of collisions and interference raise concerns about the long-term sustainability of space activities, particularly in the low-Earth orbit and geostationary orbit environments. During recent years the number of satellites launched to space increased by orders of magnitude in particular due to costs reductions enabled by miniaturization and rideshare launch opportunities, as well as due to the deployment of so-called megaconstellations by private actors. In order to allow for safe operations in near-Earth space, and to ensure sustainable use of this unique resource, numerous measures are urgently needed. These include inter alia the prevention of collisions, the obligation to remove all objects after the end of their mission from the environment, active removal of existing debris, and international efforts to coordinate the traffic and manage the debris environment.

Governments, space agencies and civilian research organizations increase their efforts to build space object catalogues and to investigate the space debris population in different orbit regions. Understanding the nature and the sources of debris is a prerequisite to provide the scientific foundation for a sustainable use of near-Earth space.

Current space debris research activities to detect and characterize space debris at the Swiss Optical Ground Station and Geodynamics Observatory Zimmerwald will be illustrated with examples from the long-standing observation programs of the Astronomical Institute of the University of Bern (AIUB).

Pro ISSI Talk was recorded on May 11, 2022

“Future Food and Water Security – the Role of Remote Sensing“ with Wolfram Mauser (Ludwig Maximilians University, Germany)

Abstract: Food and water are central resources for human civilizations, yet a growing and more prosperous global population will stress the global resources. A future sustainabble development will have to a secure the supply of affordable food. This is through developing maximum efficiency in managing water, soil and mineral resources for food production. Space based remote sensing will be the indispesable data backbone, which feeds Digital Twins of each agricultural field of the Globe with the necessary information to simulate beforehand individual management decision of farmers for maximum effiency and sustainablility in securing food production. The presentation will give the theoretical background of twinning Earth Observation with advanced farm simulation models and give concrete examples on their application in the real world.

Wolfram Mauser works in the fields of hydrology, food security, remote sensing, and Earth System modeling. His major interests are in observing human impacts on Earth from space, the understanding of human-environment relations through simulation, and the impacts of limited water resources and climate change on global as well as regional food security. His book Water Resources: Efficient, Sustainable, and Equitable Use gives insights into integrative approaches towards sustainable future water use. Wolfram received his MS in Physics, MS in Geography, and his PhD in Hydrology from the University of Freiburg, Germany. He was a visiting scientist at NASA Goddard Space Flight Center and the University of Maryland and conducted extended research visits to Africa, China, India, and South America. Until end of 2021 he held the Chair for Geography and Remote Sensing at Ludwig-Maximilians-University in Munich and now supports the satellite based remote sensing services company, VISTA in Munich Germany.

Webinar was recorded on May 5, 2022

Probing Earth’s Deep Interior using Space Observations Synergistically

New special issue in Surveys in Geophysics (all papers open access until June 8, 2022)

During the last two decades, the GRACE and SWARM space missions have provided a wealth of groundbreaking results about the spatio-temporally variable gravity and geomagnetic fields of the Earth. However, more can be learned about the deep Earth’s structure by combining data of the Earth’s gravity and magnetic fields together with Earth’s rotation data routinely measured using space geodesy techniques, such as Very Long Baseline Interferometry (VLBI). The synergistic use of these three observables represents a unique way to investigate the physics of the deep Earth’s interior. In addition to the well-known correlation between the Earth’s rotation and magnetic field observed at the decadal time scale, recent studies have reported an unexpected correlation between spatio-temporal changes of the gravity field and of the magnetic field, also at the decadal time scale. Processes occurring in the liquid core and at the core–mantle boundary (CMB) are potentially responsible for this observation. The Workshop “Probing the Deep Earth Interior by using in synergy observations of the Earth’s gravity and magnetic fields, and of the Earth’s rotation” held at the International Space Science Institute (ISSI, Bern) on 1–4 September 2020, gathered about 40 scientists from different horizons and expertise to discuss this novel research topic. The different sessions successively addressed the capability of the gravity and magnetic fields, and Earth rotation observations to detect deep Earth signals on interannual time scales, the current knowledge of processes occurring in the fluid outer core, at the CMB and within the lower mantle, as well as the present-day status of theoretical models describing the deep Earth structure.

This Special Issue gathers together overview articles that provide state-of-the-art knowledge on the various aspects of this emergent research area. It addresses different timescales associated with these deep Earth observed signals as well as associated modeling aspects.

This special issue will be reprinted as as the Volume 85 in the Space Science Series of ISSI and is edited by Veronique Dehant, Mioara Mandea, Anny Cazenave and Lorena Moreira.

Oscillatory Processes in Solar and Stellar Coronae

New Topical Collection published in Space Science Reviews (partial open access)

In 2019, the solar physics research community celebrated the 50th anniversary of the first detection of oscillatory processes in the solar corona as a quasi-periodic pulsation (QPP) of an X-ray and radio emission produced by a solar flare.

The International Space Science Institute in Beijing (ISSI-BJ) hosted the Workshop “Oscillatory Processes in Solar and Stellar Coronae” on 14–19 October 2019. This event was attended by more than forty specialists from more than ten countries. Outcomes of the workshop resulted in this Topical Collection which consists of seven comprehensive review papers. The reviews cover cutting-edge recent results obtained on the analysis and theoretical modelling of several most intensively studied coronal MHD wave phenomena, namely, kink and sausage oscillations, and running and standing slow waves. A dedicated review assesses the consistency of proposed theoretical mechanisms for heating of the coronal plasma by various MHD waves. Another review summarises the current state of the physical mechanisms and observational properties of QPPs in solar flares and considers their analogy with QPPs in stellar flares. An important discussion of novel data analysis techniques designed recently for MHD seismology applications is subject to a special paper. 

This Topical Collection will be reprinted as the Volume 76 in the Space Science Series of ISSI and is edited by Valery M. Nakariakov, Dipankar Banerjee, Bo Li, Tongjiang Wang, Ivan Zimovets and Maurizio Falanga.

Complete Topical Collection: Oscillatory Processes in Solar and Stellar Coronae”, edited by Valery M. Nakariakov, Dipankar Banerjee, Bo Li, Tongjiang Wang, Ivan Zimovets and Maurizio Falanga

Introductory Article: Nakariakov, V.M., Banerjee, D., Li, B. et al. Editorial to the Topical Collection: Oscillatory Processes in Solar and Stellar Coronae. Space Sci Rev 218, 13 (2022). https://doi.org/10.1007/s11214-022-00888-1

“The Habitability of Galaxies and the Spread of Life” with Raphaël Gobat (Catholic University of Valparaíso, Chile)

The idea of a plurality of worlds, in which the Universe is filled with a vast number of life-harboring planets similar to our own, has long fascinated philosophers and has become a durable part of popular culture. To this day no incontrovertibly habitable planet other than our own has been found, and this idea thus remains a bright hope. However, the rapid pace of exoplanet discoveries, and the large number of extrasolar planets now detected, have finally made possible statistical studies and the determination, albeit tentative, of true planetary distribution functions. Furthermore, our knowledge of the evolution of galaxies and the stars they contain is now mature enough that we can model their formation history from early times to the present day. By combining the two we can estimate the amount of potentially habitable planets in our galaxy and others. More speculative yet is the idea of “panspermia”, the exchange of life-seeding material between solar systems. However, while still entirely unproven, this concept can be explored on large scales through the application of habitability models to numerical simulations, yielding insights about the efficiency of possible seeding processes in different regions of the Milky Way.

Raphaël Gobat is a tenured assistant professor at the Catholic University of Valparaíso, in Chile. After graduating from the Ecole Polytechnique Fédérale de Lausanne (EPFL), he studied at the European Southern Observatory (ESO) and obtained is PhD from the Ludwig Maximilian University (LMU) in Munich, Germany. He then went on to work as a postdoctoral researcher at the Commissariat à l’Energie Atomique et aux Energies Alternatives (CEA), in France, and at the Korea Institute for Advanced Studies (KIAS) before moving to his current position in Valaparaíso. Raphaël Gobat is an astrophysicist specializing in very distant galaxies and galaxy clusters. Always fascinated by deep time, he maintains a strong interest in the history of life on Earth, which has led him to branch off into more astrobiological research subjects as well.

Webinar was recorded on April 7, 2022

“Space Weather, Space Climate and Habitability on Earth” with Thierry Dudok de Wit (University of Orléans, France)

Until the 1980s, surprisingly few scientists were interested in the possible impact of the variability in solar activity on the Earth’s climate, until this gradually became a hotly disputed topic. For many years, there was a belief that everything boiled down to the total solar irradiance, i.e. the amount of radiated energy received on top of the atmosphere. This picture has been shattered by the discovery of many other different mechanisms that can operate on a wide range of spatial and temporal scales. More importantly, these mechanisms are coupled, requiring a comprehensive approach.

There is now strong scientific evidence for a climatic impact of solar variability that is measurable but tiny compared to the enormous impact of human activities. But the challenge of understanding the role of solar variability is far from over. One open question is what happened during the Maunder Minimum (1645-1715) when there were episodes of colder and wetter weather in some parts of the world. This puzzle can only be solved by bringing together multiple clues (so-called proxies of past solar activity) and physical models.

In this quick overview of the main mechanisms, the speaker will highlight some of the challenges posed by this fascinating interaction between our habitable planet and our nearest star.

Thierry Dudok de Wit is a professor in solar-terrestrial physics at the University of Orléans, France. He graduated and obtained his PhD at the Polytechnic Federal School in Lausanne. He has many interests as he held different positions and gradually migrated from the fields of fusion plasmas to fluid turbulence, followed by dynamical systems and now solar terrestrial-physics. The common thread is a strong interest in methodological approaches to characterise physical processes. Today he’s deeply involved in the Parker Solar Probe mission as instrument lead CoI.

Webinar was recorded on March 31, 2022

“Life as an Agent of Sustaining Habitability” with Aditya Chopra (Visiting Fellow, Australian National University, AU) 

The pre-requisites and ingredients for life seem to be abundantly available in the universe. However, we have yet to find any evidence for extraterrestrial life. Our search for life beyond the solar system is steadfastly focused on searching for habitable planets. But what do we mean by ‘habitable’? Habitable for whom, and for how long? It is not clear that the conditions for the emergence of life (the Abiogenesis Habitable Zone) are the same as the conditions for sustaining life on a planet. Conventional models of habitability that consider mostly the physics and chemistry of habitability may not be sufficient to truly appreciate the ‘evolution of habitability’.

As a planet evolves, it may lose the potential for life to emerge but may still support a biosphere. Indeed, it may lose habitability altogether, as has been speculated has happened with Venus and Mars. In this talk, Adi will argue that biospheres could play a crucial role in maintaining habitable conditions on their host planets by interacting with the planetary environment.

If it is the case that only inhabited planets are habitable, then we have so far ignored what may be the dominant parameter controlling the habitability of a planet: the life on it.

Aditya Chopra is a visiting fellow at the Research School of Astronomy and Astrophysics at the Australian National University. Aditya is using our current knowledge about the origin and evolution of life on Earth over the last ~4 billion years to better understand the potential for, and the nature of, life elsewhere in the universe. One of his research themes is the investigation of the role that life plays in keeping its planet habitable, and to identify processes which might have been co-opted by life to regulate Earth’s habitability at different epochs. Such biotic processes might also offer detectable biosignatures of alien life beyond Earth! Aditya has spent time as a Marie Skłodowska-Curie Postdoctoral Fellow at the University of Groningen in the oLife Fellowship Programme. He has degrees in Chemistry and Astronomy and completed his PhD at the Research School of Earth Sciences and Mt Stromlo Observatory at The Australian National University.

Webinar was recorded on March 17, 2022


Marco Velli is elected as the Johannes Geiss Fellow 2022

The International Space Science Institute ISSI is proud to announce

Prof. Marco Velli

(Space Physics at the Earth, Planetary and Space Sciences Department,  University of California, USA) as the Johannes Geiss Fellow 2022.

Marco Velli, Johannes Geiss Fellow 2022

Marco Velli is Professor of Space Physics at the Earth, Planetary and Space Sciences Department,  University of California, Los Angeles, USA. A student of the University of Pisa and Scuola Normale Superiore, he has spent research periods at the University of St. Andrews, Scotland, the Observatoire de Paris, France, Università della Calabria, Italy, and the Smithsonian CfA, Cambridge, MA, as well as the Jet Propulsion Laboratory, California Institute of Technology, where he remains a Senior Scientist.

Marco Velli’s research has focused on space plasma physics and solar magnetic activity, with many original results on the stability of magnetic structures anchored in the photosphere, wave propagation and shock formation in inhomogeneous and stratified plasmas, nonlinear evolution of current sheets and magnetic reconnection, the properties of turbulence in dynamically forced, open systems and wave particle interactions in the solar corona and heliosphere.

Prof. Velli carried out a complete analysis of the propagation of Alfven waves in stratified stellar atmospheres, showing how total reflection is never achieved and providing a general discussion of the profile of the transmission into the solar wind. He was also among the first to suggested that wave reflection plays a role in the formation of the turbulence spectrum seen in the solar wind. This work was the basis for the election to AGU fellowship in 2014. Prof. Velli demonstrated the dynamical reason the solar wind is supersonic and showed that generally speaking subsonic flows connecting a star to the interstellar medium survive only over a vanishingly small range of parameters. In other words stars either accrete material or emit supersonic winds connecting with a shock to the interstellar medium. To study solar wind turbulence via numerical simulations, Prof. Velli developed the expanding box model. More recently, together with his students he showed that Sweet Parker current sheets cannot form in space plasmas generally, and that the tearing instability proceeds on ideal time-scales.

Professor Velli played a major role in the development of Parker Solar Probe (PSP), the first spacecraft to fly within 9 solar radii of the Sun’s surface to directly study the outer solar corona and acceleration region of the solar wind, as well as in the Science Definition team for Solar Orbiter. Marco Velli has taught mechanics, electromagnetism, astrophysics, and plasma physics courses at the University of Florence and UCLA. He has been member of peer review committees for NASA research and payload proposals, and member of the Space Science and Exploration working group for the European Space Agency (ESA). He has published over one hundred peer-reviewed research papers involving many international collaborators, as well as invited papers and lecture notes.

At ISSI Marco Velli plans to work on a book on the expansion of the corona into space and formation of the heliosphere in the light of the new data of Parker Solar Probe. He will also participate in relevant ISSI Teams and continue collaborations using Parker and Solar Orbiter data to shed light on the sources and evolution of the solar wind and embedded turbulence.

The Fellowship is named after Prof. Johannes Geiss, the founder of the institute.

ISSI had received excellent proposals from top level scientists from which the selection committee chose the eighth JGF recipient after thorough evaluation. The selection committee consisted of the Directors and the Chair of the ISSI Science Committee.

ISSI is honored by the high interest from the science community in the Johannes Geiss Fellowship and would like to deeply thank all applicants.

“Is Water and Rock all that is Needed? Geology, Life and Habitability” with Frances Westall (CNRS Orléans, France)

The classical definition of the habitable zone around a host star is the zone of orbits that allows liquid water on a planet’s surface, which recognizes the importance of water for life as we know it. Add rock with its nutrients, the CHNOPS elements (carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur) to the recipe and you have all you need to make life flourish. Or have you?  How about the supply of energy and the thermodynamic disequilibrium that is needed? What does this mean for the environments in which life emerged on Earth? Hypotheses range from deep sea vents, to beaches, to rivers and lakes or subaerial hot springs on land, and even deep faults! If life emerged on land and not in the sea, this precludes the appearance of life on the icy satellites in our Solar System or on ocean worlds.

Whatever the environment (and hydrothermal systems, whether subaqueous or subaerial, are the most popular), life emerged on Earth probably during the Hadean era (4.5-4.0 Ga) and appeared to have evolved very rapidly because, by 3.5 Ga, the more primitive chemotrophs (microbes obtaining their energy from oxidation of inorganic or organic substances) were joined by the more efficient phototrophs (that obtain energy from sunlight). These organisms were anaerobic, i.e. required environments without oxygen.

However, further evolution required substantial changes, not only the evolution of the oxygenic phototrophs that excreted oxygen, thereby oxidizing the surface of the Earth as well as the atmosphere, but also geological and tectonic changes to the Earth. Plate tectonics contributed to burying carbon, exporting it from the sediments and atmosphere and allowing oxygen levels to rise. Plate tectonics also recycles essential nutrients. A planet without plate tectonics would not remain habitable after all nutrients at the surface had been utilized. 

All of these factors need to be taken into consideration when looking for life elsewhere, in our Solar System or on exoplanets.


Frances Westall is director of research at the Centre de Biophysique Moleculaire Equipe exobiology of the French National Research Laboratory CNRS in Orléans.  The CNRS laboratory is associated with the Université d’Orléans.  Frances was born in Johannesburg, South Africa but grew up in the UK and studied geology at the University of Edimburgh. Her research focuses on the earliest life on Earth and its geological context. She does field studies of the earliest supracrustal terrains – including the Kapvaal Craton in South Africa and the Pilbara in Australia – and of fossil bacteria from the early Archaean. She is a leading member of the ESA ExoMars mission science team to search for life on planet Mars.

Webinar was recorded on March 10, 2022