ISSI Tuesday Tea(m) Time 1551

Report by Joachim Wambsganss, ISSI Director

Following the interruption of the usual activities at ISSI in Bern due to the Corona crisis, the ISSI directorate discussed other/new/additional ways to promote and enable international space science. We came up with three new initiatives, the first of which started on July 14, 2020: ‘ISSI Tuesday Tea(m) Time 1551’ and will be presented here.

The idea behind it is as follows: Due to national and international travel restrictions, regular full physical meetings at ISSI Bern are presently difficult. This is of particular concern to the ISSI International Teams. International Teams consist of 8 to 15 scientists and typically meet in Bern at the ISSI premises two or three times within roughly two years. At any given time, about 50 International Teams are “active”. Since mid-March, no meeting of an International Team has taken place at ISSI although the first physical meetings will likely resume in September.  

To provide support to International Teams, the ISSI directorate came up with the suggestion to meet “virtually” in form of video conferences. In order to structure this and to give ISSI scientists a chance to participate, we fixed a weekly slot, Tuesdays at 15:51 o’clock Bern time (i.e. CEST or CET, respectively). So ideally, every Tuesday a different team shall meet within the next so many months. The slightly odd-looking time-of-day was chosen because the numerals 1551 look very similar to the letters ISSI and hence have a visual connection and can be easily remembered as well. Since on one hand, this afternoon time is when many cultures celebrate a cup of tea, on the other hand we want each ISSI Team to use this opportunity, we call this new activity: 

ISSI Tuesday Tea(m) Time 1551

(or in short ISSI TTT 1551). Most of the International Teams responded positively, some embraced this new opportunity of a soon-to-be-held team meeting enthusiastically.

The first actual “ISSI TTT 1551”-event took place on Tuesday this week, July 14, 2020. The ISSI International Team An Exploration of the Valley Region in the Low altitude Ionosphere: Response to Forcing from Below and Above and Relevance to Space Weather lead by Jorge Chau (Leibniz Institute of Atmospheric Physics, Rostock, Germany) met online via the ZOOM system, the session had been prepared by ISSI.

Screenshot of the first Tuesday Tea(m) Meeting with the J. Chau Team and ISSI Staff Members














This “ISSI TTT 1551”-premiere worked very well. After a few introductory words by ISSI representatives, the team chair Koki Chau presented a draft agenda for the meeting. First some administrative issues were discussed, e.g. whether the next envisioned physical meeting team meeting at ISSI Bern – foreseen for end of September – could or should be held, maybe combined as a hybrid meeting with remote participation possible. Then the team discussed how to proceed with another new ISSI activity, namely an ISSI@25 video, meant to celebrate 25 years of ISSI with a 25 second video per International Team (this will be reported about in the near future with a separate spotlight). Following a brief status of activities, three short science talks (10 min each) were presented by team members followed by a Q&A period. A general discussion concluded the meeting.

This first ISSI TTT 1551 was an excellent realization of our vision at ISSI of how such a meeting should work. Five ISSI staff members participated, at least for part of the time. They enjoyed the opportunity to meet the team and get an excellent impression on what their science is all about as well as of the enthusiasm of the team members. This team was an excellent pioneer and did extremely well from our ISSI perspective. We certainly hope that the team enjoyed their Tea Time as well. We look forward to many more interesting and exciting ISSI TTT 1551 events with other active ISSI International Teams in the coming months!

Obituary Prof. Johannes Geiss (1926-2020)













It is with great sadness that we must bid farewell to our founding father and honorary director

Prof. Johannes Geiss (1926-2020)

Johannes Geiss died on January 30, 2020 at the advanced age of 93. In him, we have lost a great scientist and supporter of the sciences forever.

Johannes Geiss was born on September 4, 1926 in Stolp in what was then Western Pomerania as the son of an estate manager. How different the world must have looked in that time, when his grandfather had the horse hitched to the cart every two days in order to travel to the barber in the neighboring village for a shave; not fifty years later, his grandson landed an experiment on the Moon.

During the war years, Johannes Geiss was able to attend Gymnasium (high school), which he left in 1944 with a Notabitur (early school-leaving qualification in wartime) in order to immediately start a physics degree in Göttingen. Even then, his lecturers must have been struck by the young student’s rapid comprehension and irrepressible need to communication, and he was thus employed as a teaching and research assistant even during his studies. In 1950, he obtained a degree in physics from Max von Laue, and he obtained his doctorate from Wolfgang Paul in 1953. The latter he referred to, with the greatest respect, as the real part of the equally well-known but more flamboyant Wolfgang Pauli, who worked at the ETH at the time; Geiss loved such wordplays which reveal themselves to mathematical initiates.

During his time in Göttingen, Johannes Geiss also met his wife, Carmen, with whom he shared a deep partnership all his life.

His first position as a physicist brought Johannes Geiss to Fritz Houtermans’ institute at the University of Bern. Houtermans wanted to apply mass spectrometry, with which Geiss had successfully been able to determine the isotopic composition of lead, to determine the age of meteoric matter. So, at the beginning of the fifties, his glass mass spectrometer with him, he went to Bern, which would become the new center of his life, and by 1974 he was a naturalized citizen of Switzerland.

Johannes Geiss brought a breath of fresh air to an institute which was perhaps a little outdated at the time and soon found enthusiastic companions to establish a group which would quickly make a name for itself in astrophysics. Periods spent abroad in Chicago with Harold Urey and as a young professor in Miami broadened and rounded out his education; in between, he habilitated in experimental physics, in particular extraterrestrial physics, at the University of Bern in 1957. He was appointed as an associate professor in 1960, and as a full professor in 1964. At the beginning of the sixties, he had to take over management of the institute for the increasingly ill Houtermans, and was thus appointed director of the institute following Houtermans’ death in 1966; a position which he held until his retirement in 1990. In 1970/71, he also served as dean of the Faculty of Science, and in 1982/83 he served as rector of the university.

But Johannes Geiss was pulled to other places time and again in order to maintain and develop his ever-growing network. He spent the year before the first landing mission to the Moon – Apollo 11 – at NASA in Houston in order to lobby for the ingeniously simple solar wind sail developed by him and his group. The solar wind would be captured with an aluminum foil during the astronauts’ time on the surface of the Moon as the solar wind arrives there unhindered because of the Moon’s lack of an atmosphere and a magnetic field. The simplicity of the experiment and the excellent reputation of the Bernese mass spectrometer made him perfect for the job. But it took great tenacity, coupled with the previously mentioned enthusiasm and the necessary bit of luck for the sail, which weighed scarcely a pound, to fly with Apollo 11 in July 1969 and then a further four times. Its analysis, in particular the ratio of the helium isotopes captured, corresponded to a measurement of the average density of the universe as a whole – a ground-breaking result for which he, together with Hubert Reeves, was awarded the Einstein Medal by the Albert Einstein Society in Bern in 2001.

Johannes Geiss made clever use of his growing reputation in order to continue improving the conditions in Bern and to make the institute one of the top names in astrophysics and keep it that way. Under his leadership, the mass spectrometer was made so much smaller that it could be flown on space probes. At the same time, he was able to realize the necessary laboratories and a top-notch clean room in Bern for the tests and calibration. Bern thus became an internationally sought-after partner for space missions, a role which it still retains today thanks to the tireless efforts of Johannes Geiss and his successors. Of the many missions which Johannes Geiss was involved in as principal investigator or as co-investigator, the solar wind ion composition spectrometer stands out as a prime example. Developed with his friend George Gloeckler, this instrument orbited the sun on the Ulysses space probe for almost two decades on a polar orbit. This experiment achieved (among many other results) a refinement of the isotopic signature of helium measured with the solar wind sail. It is hard to find a better illustration of his progressive, unceasing spirit of research.

Even after his retirement, Johannes Geiss’ drive diminished not one jot. He still mustered all of his enthusiasm and convinced those in charge of the European Space Agency ESA and the Swiss Space Center to establish a new institute which would focus on the interdisciplinary analysis, evaluation and interpretation of the results of space missions. The International Space Science Institute was thus born almost exactly 25 years ago. In the first eight years, he served as its executive director and made the institute a center where scientists from all around the world come together in an informal and interdisciplinary setting in order to reach for new scientific horizons. Thanks to his vision, the ISSI has today become a place of meeting and exchange for thousands of space scientists.

Johannes Geiss’ work was internationally recognized with many distinguished honors. He didn’t like the often stiff atmosphere of such events, greatly preferring informal discussions with colleagues, students and anyone at all, when it came to science or any other topic which sparked his enormously broad and active interest. However, some of these honors filled him with a certain amount of pride – and deservedly so: His appointment as a Foreign Associate of the National Academy of Sciences of the USA (1978), his honorary doctorate from the University of Chicago (1986), the aforementioned Einstein Medal (2001) and the Bowie Medal, the highest honor of the American Geophysical Union (2005).

Johannes Geiss passed away in his sleep on January 30, 2020 surrounded by his loved ones. He leaves behind his wife Carmen and his daughter Jana, with her family. His legacy will continue to shine at the Physics Institute at the University of Bern and at the International Space Science Institute.

Bern, February 6, 2020
Rudolf von Steiger


Nachruf Johannes Geiss (Deutsche Version) >>

In Memoriam: Johannes Geiss  – Obituary written by Len A. Fisk and Roger-Maurice Bonnet >>

Pro ISSI Nachruf Johannes Geiss >>

Dr. Anny Cazenave, ISSI Earth Science Director, Receives the 2020 Vetlesen Prize for her Pioneering Work in Charting Modern Sea Level Change

Dr. Anny Cazenave is to receive the most prestigious Vetlesen Prize 2020 for Achievements in the Earth Sciences.

The Vetlesen Prize is designed to be equivalent to the Nobel prize and will be administered at a ceremony at Colombia University this spring. Cazenave, a geodesist by training,  will be honored for pioneering the use of space satellite data to measure the topography and the rise of the surface of the oceans, together with related changes in ice sheets, glaciers, ocean temperature and land water storage. Her work has linked the sea level rise with climate change.

Sea level rise is seen as one of the most important and threatening consequences of climate change. Two thirds of the sea level rise is now understood as coming from the melting of land ice as a direct consequence of global warming and one third from the expansion of ocean water. That ratio was only half to half when Cazenave started her work.

As director of ISSI’s Earth Science Program Anny Cazenave has supervised the program and has organized a significant number of workshops related to global change. ISSI is proud to have her on the scientific staff.

The Vetlesen Prize is awarded every three years for “scientific achievement resulting in a clearer understanding of the Earth, its history, or its relation to the universe”. The prize was established in 1955 by George Unger Vetlesen, a Norwegian born sailor, naval engineer and shipbuilder in the United States.


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