German born Johannes Geiss was a man ahead of his times. Straddling two continents, Europe and the US, throughout his very accomplished scientific career. Alternating between Bern, Chicago, Miami, Washington DC, and New York, Johannes Geiss became a strong advocate for international collaboration in science as a way to advance knowledge and unite humanity. As a young scientist, he travelled to the US to work at the Enrico Fermi Institute for Nuclear Studies in Chicago in 1955 but kept his connection with Europe and especially Bern, where eventually, in 1966, he became the Director of the Physikalisches Institut. These were formative years for Johannes Geiss, that shaped his future vision for science. In addition to the deep motivation to develop international collaborations and partnerships, we see the emergence of a very novel multidisciplinary approach to solving scientific problems.

Johannes Geiss’ pioneering research on meteorites broke new grounds when he connected the results of his rock sample analysis with the solar wind. It had been known for years that some meteorites contained noble gases, wrote Hans-Joerg Schlaepfer in his extensive biographical article (SPATIUM #27, SEPTEMBER 2011), but Johannes Geiss showed that these gases were located in thin surface layers of tiny grains inside the meteorites, and their elemental composition and their location suggested the solar wind to be their origin. This work inspired the Solar Wind Composition (SWC) experiment, developed at the University of Bern, that first flew on NASA’s Apollo mission.

The experiment was designed to collect solar wind particles. It had to be operating in space, beyond the Earth’s magnetosphere. The NASA Apollo mission to the moon offered such an opportunity, and an unsolicited proposal to NASA was accepted for the SWC, nicknamed “Swiss Solar Sail”, to fly on the historical Apollo 11 mission in 1969. The SWC foil was deployed on the moon surface by astronaut Edwin “Buzz” Aldrin, and then rolled up and brought back to Earth to be analysed. The experiment was so successful that it was flown four more times on subsequent Apollo missions.

Johannes Geiss’ brilliant career did not stop at this stage – enriched by his collaborative experience with NASA and the US, he was instrumental in establishing a parallel partnership of Switzerland with ESRO and subsequently ESA.

Johannes Geiss felt that there was an absolute need for the Swiss space community to have an internationally recognised forum where a free and independent exchange of scientific ideas could happen. In the 80’s and 90’s, an impressive array of space missions, on either side of the Atlantic, such as Giotto and later SOHO, were producing large quantities of data, but the community was ill-prepared to take advantage of this new “golden era” of the space sciences. Space instruments were getting increasingly complicated, and the datasets they produced were complex.

The idea of creating an institute rooted in the concept of Science First, designed to facilitate the scientific discourse in a multi-disciplinary setting, and ambitiously focused on pushing to the maximum the scientific outcome of space missions, started taking traction. Prominent astronomers in Switzerland supported the idea. Roger-Maurice Bonnet, who had been Director of Science at ESA since 1983, and Reimar Lüst, ESA Director General, immediately saw the benefit of highlighting the scientific results from the huge mission investments that ESA had made. The Swiss government saw the potential for scientific leadership for their scientific community, at a national and international level. One first idea was to have the Inter-Agency Consultative Group (IACG) involved in setting up this new institute, but eventually, a partnership developed between ESA and the Swiss government, to provide the financial infrastructure for such institute to operate. Interestingly, the IACG included other space related international entities, such as JAXA/ISAS, NASA and what was at the time the Intercosmos Council of the Soviet Academy of Sciences.

Guided by his lifelong commitment to international collaborations, and having secured the principal stakeholders, Johannes Geiss did not stop, but went one step further because he knew that in order to be truly successful, his dream institute needed to have worldwide reach. So, he reached out to Prof. Sagdeev from the Soviet Academy of Sciences, and to NASA Associate Administrator Prof. Len Fisk in the US. Prominent scientists from the Swiss scientific community and industry also supported the ambitious idea.

Finally, in early 1994, the Canton of Bern gave their commitment and ISSI was established as a foundation on January 31, 1995. Johannes Geiss stayed at the helm as the first Executive Director, aided by friend and colleague Rudolf von Steiger as Senior Scientist. A Board of Trustees was established, and one of their first actions was to rent the premises at Hallerstrasse 6, where ISSI is still hosted today. The very first workshop that took place at ISSI in November 1995 was focused on the study of “The Heliosphere in the Local Interstellar Medium” and was a resounding success.

Johannes Geiss’ vision had become a reality.

Johannes Geiss sadly passed away in 2020, but his spiritus rector lives on in the hallways at ISSI. His dream institute stood the test of time and is stronger than ever. At ISSI, we welcome more than 1000 visiting scientists per year. The multi-disciplinary nature of the institution is preserved and defended. It is not a coincidence that ISSI is located in Bern, a town rich in history and tradition, nested in between beautiful mountains and in the heart of Europe. ISSI Bern offers a quaint, neutral environment that is especially welcoming to visitors from all over the world, where it is possible to hold heated scientific discussions among collaborating or competing teams, and still celebrate science at the end of the day, together, in front of a warm fondue.

In the 30 years from its inception, ISSI has grown. It now occupies three of the four floors of the original building, with state-of-the-art meeting rooms and technology to reach out seamlessly to a large community worldwide. Some new initiatives have been put in place to greatly complement the scientific activities that have made ISSI such a unique place in the years. In addition to our core of dedicated and committed Staff and Directors, ISSI hosts two Fellows, five Discipline Scientists, one Johannes Geiss Senior Fellow, who all keep Johannes Geiss’ dream alive every single day by sharing his vision and furthering his goal.

They all join me as we kick off the celebrations of the 30^th anniversary of this very special institute, to pay homage to a visionary man who understood that through science you can change the world for the better and, every day, we are inspired and honoured to play our small part.

Antonella Nota