A Word form the ISSI Executive Director

Dear friends of ISSI,

Dear visitors of our web site,

As you all know, we have entered into the second year of the COVID-19 pandemic. The institute continues to be a quiet place with staff working mostly from home as is required by Swiss law. Visits to ISSI require testing on the way to Switzerland and back and I – for one – have gotten quite used to having regular PCR tests. To date, none of the staff has been infected, fortunately, and some of us have received their (first) vaccination shots. We – like everybody else – hope that the vaccination campaign speeds up and that indeed people can be vaccinated by the summer or by the end of the season.

While the institute remains a quiet place ISSI activities are continuing (compare our Annual Report just published). International Teams and Working Groups continue to be meeting online. The “Global Change in Africa” workshop was held in January with most participating remotely as was the “Tipping Points in the Earth’s Climate”- Forum the same months. The “Venus: Evolution through Time” as well as the “The Heliosphere in the Local Interstellar Medium” and the “Strong Gravitational Lensing” workshop teams are proceeding following the new alternative scheme for the workshop-to-book process in which the chapter writing starts after an online kick-off and with regular online tag-ups. The in-person workshop will be organized as the pandemic allows in the flow of the project and will be largely devoted to discussions of the then matured subject. Other workshops and forums are still postponed, however, waiting for the end of the crisis.

Our online seminar series about missions that changed the game in the space sciences has ended with the month of March, after 28 lectures had been given. Recordings of these are available here on our website and continue to be downloaded often. The ISSI directorate decided to continue the series albeit changing gears to some degree. Rather than presenting missions, we will during the months of May to July look at “Ideas and Findings about the Solar System, the Universe and our Terrestrial Environment”. The first talk will be on tipping points in the Earth’s climate on May 6thand we will then proceed to present a wide variety of subjects in Earth, Solar and Planetary sciences and Astrophysics (see the schedule here). We are extremely proud to have been able to recruit leaders of their fields as speakers, including 2020 physics Nobel laureate Reinhard Genzel. Come and join us for these extraordinary events!

Stay safe and I hope to meet you all in person at ISSI sometime soon!

Tilman Spohn


ISSI executive Director

Job Posting: Director (part-time position)

The International Space Science Institute (ISSI) in Bern, Switzerland, invites applications for a part-time position of




The new Director is expected to spend about 30% (negotiable) of her/his time working for ISSI at the Institute’s premises in Bern, Switzerland, starting in October 2021 or by agreement. The appointment will be for a period of four years renewable once.

Under the leadership of the Executive Director, each of the Directors of ISSI provides the inspirational scientific environment of the Institute in her/his area of research, namely, (i) Earth Observation, (ii) Solar and Plasma Physics (iii) Planetary Sciences, and (iv) Astrophysics and Cosmology. The directors are the driving force behind the various activities taking place at ISSI in their fields of research: scientific workshops, forums, working groups and international teams. Their recognized scientific stature ensures the visibility and guarantees the high scientific standards of the Institute.

Scientists corresponding to the above profile, working in any area of space sciences covered by ISSI’s activities (with the exception of Earth Observation, for which a separate specific call has been already issued) are encouraged to apply.  Further information about the organisation of the International Space Science Institute and its activities can be found at www.issibern.ch or by contacting the chair of the Selection Committee:

Prof. Georges Meylan
Laboratory of Astrophysics
Ecole Polytechnique Fédérale de Lausanne
E-mail: Georges.Meylan@epfl.ch

Interested scientists should submit their applications – a letter of motivation and curriculum vitae in one single pdf file – to the secretariat of ISSI, at their earliest convenience but no later than May 31, 2021:

Silvia Wenger
International Space Science Institute
Hallerstrasse 6
3012 Bern


Full Job Announcement Director >>



Understanding the Diversity of Planetary Atmospheres

New Topical Collection published in Space Science Reviews

Ten planetary atmospheres are currently studied in the solar system and many more will be characterized in the coming years as we remotely observe exoplanets. Are we ready to understand what we will discover around other stars? The examples of the solar system are probably not sufficient to let us anticipate the diversity of exo-atmospheres. To prepare this revolution, it is nevertheless very interesting to make the most of what we have learned so far, to identify commonalities between the different solar system atmospheres, and to make out the remaining key questions in our understanding of the known planetary atmospheres.

Toward these goals, a special article collection on “Understanding the Diversity of Planetary Atmospheres” has been published in the journal Space Science Reviews. It was prepared during a Workshop organized at ISSI, on November 12-16, 2018, with the support of the Europlanet Research Infrastructure of the EU. Nearly 40 scientists from Europe, USA, Russia, China, Japan, Israel and Australia attended this meeting, including planetary scientists, experts in the origins of atmospheres, planetary interior, aeronomy, escape, climatologists, and astronomers. The diversity of expertise proved to be very fruitful to discuss the diversity of atmospheres.

The 15 articles of this topical collection present rich, up-to-date views on many hot scientific questions relating to planetary atmospheres and the climate of exoplanets. By compiling this collection we hope to provide a solid reference for anyone willing to work towards understanding the diversity of planetary atmospheres. 

Find here the Editorial of the Topical Collection on Understanding the Diversity of Planetary Atmospheres (Open Access), Space Sci Rev 217, 51 (2021). https://doi.org/10.1007/s11214-021-00820-z

This collection is dedicated to the memory of Adam P. Showman, a creative thinker, brilliant scientist, pioneer and leader in the study of the diversity and dynamics of planetary atmospheres.


François Forget, Oleg Korablev, Julia Venturini, Takeshi Imamura, Helmut Lammer & Michel Blanc (Guest Editors)

Find here the complete Topical Collection Understanding the Diversity of Planetary Atmospheres in Space Science Reviews >>

This Topical Collection will be reprinted as the Volume 81 in the Space Sciences Series of ISSI.

Job Posting: Science Program Manager and Researcher (100%)

The International Space Science Institute ISSI in Bern, Switzerland invites applications for the staff position of

Science Program Manager and Researcher

(full-time staff position under Swiss law)

starting August 1st, 2021.

We offer a full-time position of unlimited duration in a small team serving a large international community. The salary will be commensurate to qualifications and experience. Employment conditions are like at the nearby University of Bern.

The duties of the Science Program Manager include all activities in the Institute’s Science Program, which covers the Space and Earth Sciences.

The Science Program Manager will ensure liaison with the scientific community in all scientific aspects related to their involvement in ISSI activities. She/he will

  • assist in the organization of workshops, working groups, forums, and ISSI International Teams.
  • prepare the annual calls for applications for International Teams.
  • evaluate applications for International Teams to assess their support requests and compatibility with the Institute’s goals and resources.
  • manage the scientific peer review of International Team applications and results.
  • liaise with the team leaders in all matters related to the activities at ISSI.
  • oversee the program supporting the participation of young scientists in ISSI activities.
  • support the ISSI Scientific Committee as its secretary.

The Science Program Manager will support the ISSI Directorate in

  • maintaining relations with scientific organizations, such as the Secretariat for Education, Research, and Innovation (SERI), the European Space Agency (ESA), the Swiss Academy of Sciences (SCNAT), and support the preparation of funding proposals or contracts with these organizations.
  • the monitoring of progress and development of contracts with these organizations.
  • the regular reporting to these organizations and their committees, if requested.
  • the continued monitoring of the conduct of ISSI’s scientific activities and the participation of the scientific community in those activities.
  • the formulation of the future scientific perspectives of the Institute’s program.
  • the preparation of a periodic assessment of the Institute’s performance.
  • the communication of ISSI results and activities to the general public.

The Science Program Manager will conduct her or his own research and should

  • apply for own research funding.
  • publish the results in the peer reviewed literature.
  • actively keep an international research profile.


Full Job Announcement >>


Wind and Waves on the Ocean Surfaces: Insights from the CFOSAT Mission with Danièle Hauser (IPSL, France)

The wind and ocean surface waves are key parameters affecting ocean / atmosphere exchanges, marine meteorology and upper layers of the ocean. More generally, sea-state parameters are essential variables of the climate system. They also have an impact on marine resources, off-shore economy and security, and coastal environments. To progress in the understanding of the ocean / atmosphere coupling, in its numerical modeling, as to further develop applications in oceanography, it is necessary to observe the wind and waves at a global scale. Altimeter satellite missions, in space since the 1990s, provide limited information on waves, while other satellite missions are dedicated to measuring winds over the global ocean. Since 2018, a new satellite called CFOSAT (China France Oceanography SATellite) is in orbit. Thanks to its original concept, it allows simultaneous description of wind and waves with details on ocean wave properties that were not previously accessible. This brings new perspectives to study ocean / atmosphere exchanges, improve wind and wave forecasting, study the impacts of climate change on the ocean surface. During this seminar, the spreaker will present a summary on wind and wave measurements from space and highlight the new contribution of the CFOSAT mission.

Danièle Hauser is a senior scientist with CNRS (Centre National de la Recherche Scientifique, France). She develops her research at LATMOS (Laboratoire Atmosphère Milieux Observations Spatiales), a laboratory funded by CNRS, by “Université de Versailles Saint-Quentin-en Yvelines” and by “Sorbonne University” and located in the Paris area (France).  She works on the physical processes taking place at the ocean surface, and more particularly on exchanges at the air/sea interface driven by wind and waves. She is an expert in developing new systems for ocean surface observations using remote sensing techniques. She is the Principal Investigator of the CFOSAT (China France Oceanography SATellite) mission which has been launched in 2018 and currently provides unique observations of surface wind and ocean waves. In recent years, she has also held various research management responsibilities, in particular she was director of LATMOS (2009-2013), as well as deputy scientific director at INSU (2014-2018).

Seminar was recorded on March 25, 2021


“Exploring the Earth’s Time-Variable Gravity Field using Satellite Observations” – Pro ISSI Talk with Adrian Jäggi

A new era in satellite gravimetry was initiated with the launch of dedicated gravity missions such as CHAMP (2000–2010), GRACE (2002–2017), GOCE (2009–2013), and the still on-going GRACE Follow-On (GRACE-FO) mission that was launched in 2018. Whereas CHAMP and GOCE significantly improved our knowledge of the Earth’s static gravity field, GRACE and GRACE-FO were/are mainly devoted to measure its tiny variations in time by providing monthly snapshots of the Earth’s gravity field.

Time-variable gravity as derived from ultra-precise GRACE/GRACE-FO inter-satellite ranging is the only observable to provide integrative measures of total water storage variations on a global scale, i.e., the sum of groundwater, soil moisture, snow, ice, and surface water bodies. As such it is of great interest for large user communities in hydrology, climate modeling, ice observation, geodetic, geophysical, oceanographic, atmospheric, and environmental sciences.

Moreover, it is paramount for separating the variations of individual compartments that are not well accessible by combining the total water storage variations with other remote sensing data. In this talk an overview of the underlying principles of the challenging GRACE/GRACE-FO data analysis will be given and selected key scientific results will be highlighted. A special focus will be on the relevance of European and international initiatives, and in particular also on the important role of ISSI in this context, to further exploit and promote this unique observable to continuously monitor the on-going changes in our Earth system.

This talk was organised by the Association Pro ISSI and was recorded on March 24, 2021.

The Rossi X-ray Timing Explorer: Timing the Extreme Universe with Tomaso Belloni (INAF – Brera Astronomical Observatory, Italy)

The Rossi X-ray Timing Explorer (RXTE) was a satellite for X-ray astronomy launched by NASA on 30 December 1995 into a low-earth orbit. It operated for almost exactly sixteen years until its termination in January 2012. On board were three X-ray instruments a large-area Proportional Counter Array (PCA) built at NASA/GSFC, the High-Energy X-ray Timing Experiment (HEXTE) built at the University of California, San Diego, covering higher energies, an All-Sky Monitor (ASM), developed at MIT Cambridge.

Its characteristics, such as large collecting area, no imaging capability, high time resolution, broad energy coverage and very high flexibility of operation, together with the presence of an all-sky monitor to detect transient X-ray events, were aimed at the detailed study of bright galactic X-ray sources, in particular regarding their fast time variability. RXTE was indeed a giant step forward in our knowledge of variability of systems containing compact objects, the most powerful emitters of X-rays in our Galaxy and it allowed us to link their properties to physical models for accretion and to effects of General Relativity (GR) in the vicinity of a black hole or neutron star.

This was done through the discovery of millisecond quasi-periodic variability from accreting neutron stars in low-mass X-ray binaries, together with more elusive and slightly slower signals from black-hole binaries. These oscillations allowed us for the first time to obtain precise measurements of time scales in the accretion matter very close to a compact object, where the effects of GR are more extreme. Indeed, models based on GR frequencies have soon emerged and, although they have not been completely established, hold the promise to test GR in the strong field regime.

The long-sought missing link of neutron-star evolution was finally unveiled by RXTE: millisecond pulsations from accreting neutron stars in low-mass X-ray binaries. These systems were thought to be the progenitors of millisecond pulsars, but no pulsation was found and therefore we had no direct indication of their fast spinning. RXTE detected pulsations from several faint transient systems and sporadic pulsation from others. At the same time, evidences for neutron star rotation periods came from short-lived oscillations during nuclear explosions on the surface of the accreting neutron star. These provide powerful tools for studying properties of the compact object itself and have opened a promising avenue for putting tight constraints on the equation of state of neutron matter.

Sixteen years of operation mean a large discovery space: from the evolution of black-hole transients, to the discovery of extreme variability from peculiar objects, which can be linked to the complex phenomenon of ejection of relativistic collimated jets, to the long-term monitoring of the X-ray emission of active galactic nuclei and to the observation of signals from seismic waves on neutron stars in the case of an extremely powerful yet very rare flare. RXTE has changed our way we see accreting compact objects and has led the way to the current missions like NICER and Astrosat up to the future observatories like eXTP.

Tomaso Belloni is Research Executive at INAF – Brera Astronomical Observatory in Merate, Italy and Visiting Professor at the University of Southampton, UK. Although not directly involved in the mission, he has worked with RXTE data since its launch and continues today with the exploitation of its database, being also involved in the current Indian X-ray satellite Astrosat and the planning of the future mission eXTP. He is chair of COSPAR Commission E and vice-president of the Scientific Advisory Panel of INAF. His main research interests are in fast time variability from X-ray binaries, in particular black-hole binaries, and the search for GR effects through timing analysis.

Seminar was recorded on March 18, 2021

The Apollo Lunar Exploration Program: How Increasing Science Capabilities Resulted in a Revolutionary New View of the Moon with Jim Head (Brown University, Providence, Rhode Island, USA)

There has been hardly any other mission or mission program that has more fundamentally changed our way of understanding space than the Apollo Lunar Exploration Program. The first human landing on an extraterrestrial body, the first in-situ study by a trained geologist. The first sample return, the first extraterrestrial seismic experiment and network, the first extraterrestrial heat flow measurement, and, with particular reference to the University of Bern and ISSI, the first in-situ collection of solar wind particles, to name a few. Johannes Geiss founding father of the institute and at the time professor at the University of Bern had conceived of and built this simple and effective sensor that was the first scientific instrument installed on an extraterrestrial surface by a human being, soon after the landing of Apollo 11.   

Project Apollo landed six lunar modules and twelve astronauts between July 1969 and December 1972. It returned 382 kg of lunar samples and a wealth of data that are still explored to date. As examples we note that only a few years ago application of modern seismic data analysis tools to the historic Apollo seismograms have revealed what are arguably reflections of waves from the lunar core. Moreover, traces of water have recently been found in re-analysis of lunar samples.

In this presentation we discuss how the scientific input and science and engineering synergism during the Apollo Lunar Exploration Program resulted in ever-increasing capabilities to visit a wide range of landing sites on the Moon and to conduct geological traverses that culminated in the Apollo 15-16-17 Scientific Expeditions to the Moon. The Apollo Exploration program resulted in an entirely new paradigm for the origin and evolution of the Moon, and indeed, other planets.  Lessons for future human and robotic exploration will be described.

James W. Head is the Louis and Elizabeth Scherck Distinguished Professor of Geological Sciences at Brown University. He worked for the NASA Apollo program, in which he analyzed potential landing sites, studied returned lunar samples and data, and provided training for the Apollo astronauts. He studies processes that form and modify the surfaces, crusts and lithospheres of planets, how these processes vary with time, and how such processes interact to produce the historical record preserved on the planets. Comparative planetology, the themes of planetary evolution, and application of these to the study of early Earth history are also of interest.  Prof. Head received the Penrose Medal in 2015 as well as G.K. Gilbert Award. He is a Fellow of the American Association for the Advancement of Science, the Geological Society of America, and of the American Geophysical Union. He is a Dr. honoris causa of the Washington and Lee University. The Head Mountains in Antartica bear his name since 2007. Prof. Head has been a co-investigator on numerous NASA, ESA, Soviet and Russian missions, Including the Lunar Reconnaissance Orbiter and the European Space Agency’s Mars Express Mission

Seminar was recorded on March 11, 2021

In Search for the Exit from the Heliosphere: The Odyssey of Voyagers 1&2 Interstellar Missions (1977-2021) with Stamatios Krimigis

When the Voyager spacecraft were launched in 1977, the objective was to explore Jupiter and Saturn over the ensuing four years. At that time, estimates of the radial extent of the solar system were as small as 5 astronomical units (1 AU= 150 million km=the Sun-Earth distance). The Voyager science team, however, was fully aware of the unique arrangement of the outer planets that occurs every 175 years, enabling successive exploration of each planet through gravitational assists at each one. The endurance of the Voyager spacecraft provided the opportunity to not only explore Uranus and Neptune, in addition to Jupiter and Saturn, but also to initiate the Voyager Interstellar Mission, in search of the boundary between our solar system and the local interstellar medium (LISM). It was a long wait, since the Neptune encounter at 30 AU took place in 1989, but the heliopause was crossed some 23 years later by Voyager 1 in 2012 at 121.6 AU. The speaker has been a Voyager Principal Investigator since 1971, and will describe this remarkable journey, a modern Odyssey of the space era.

Stamatios Krimigis is Emeritus Head of the Space Exploration Sector of the Johns Hopkins Applied Physics Laboratory (APL), Counselor on Space to the Minister of Digital Governance of Greece, serves as Chairman of the National Committee for Space Research at the Academy of Athens, is Principal Investigator (PI) on NASA’s Voyagers 1, 2, and PI Emeritus on the Cassini-Huygens mission to Saturn, among others. He received B. Phys. from the University of Minnesota (1961), his Ph.D in Physics from the University of Iowa (1965) under J.A. Van Allen, served on the faculty, moved to APL in 1968, became Chief Scientist (1980), Space Department Head (1991) and Emeritus in 2004. He has built and/or participated in instruments that have flown to all nine classical planets beginning with Mariner 4 to Mars in 1965, ending with New Horizons to Pluto in 2015, and culminating with the Parker Solar Probe to the Sun launched in 2018. He has published over 630 papers in peer-reviewed journals and books with over 23,000 citations. He is a three-time recipient (1981, 1986, 2014) of NASA’s Exceptional Scientific Achievement Medal. In 1999 the International Astronomical Unionnamed asteroid 1979 UH as 8323 Krimigis. He is a Fellow of the American Physical Society (APS), the American Geophysical Union (AGU), the American Association for the Advancement of Science(AAAS) and the American Institute of Aeronautics and Astronautics (AIAA). More recent awards include the Council of European Aerospace Societies CEAS Gold Medal in 2011, the European Geophysical Union Jean Dominique  Cassini Medal (2014), the AIAA Van Allen Space Environments Award (2014), the National Air and Space Museum (NASM) Trophy for Lifetime Achievement (2015), the International Academy of Astronautics (IAA) Laurels Award for the MESSENGER Team (2015), the American Astronautical Society Space Flight Award, the NASM Trophy for Current Achievement (New Horizons Team), and the NASA Distinguished Public Service Medal, all in 2016, and the IAA Theodore von Karman Award (2017). He is a member of Academia Europaea, and was honored by a special resolution of the U. S. Senate “for exceptional contributions to space science” (2018).

Seminar was recorded on March 4, 2021