Swiss EST workshop

Swiss Virtual Institute for Solar Science (SVISS), a cooperation for solar science in Switzerland, organizes the first Swiss EST Workshop on October 8-9 in Locarno. The goal of the workshop is to provide an overview of the research in solar physics and related disciplines in Switzerland and kick-off the preparation for Swiss participation in the European Solar Telescope (EST).

The Sun is our home star that provides energy for life on the Earth, impacts the near-Earth space weather and shapes the Earth's climate. Thus, the Sun, located in the centre of our solar system, is also central to the existence of human society and terrestrial life in general. The Sun is also a reference star for astrophysics, in particular for understanding stellar structure, composition, evolution, and stellar impacts on planet formation, evolution, and habitability. As a vast plasma physics laboratory, the Sun enables us to study plasma and turbulence processes under conditions that are unavailable on Earth.

The 4.2m European Solar Telescope (EST, https://est-east.eu) will be the largest ground-based optical research infrastructure in Europe and the world to study the Sun. It will address major open questions in solar physics and astrophysics on fundamental processes in magnetized plasma, both in stars and other high-energy objects. It will reveal physics of solar variability on all scales and significantly advance our ability to forecast solar activity and its impact on Earth. The EST will surpass the current national large solar optical telescopes in Europe operated, e.g., by Germany, Sweden, France and Switzerland, by achieving the highest spatial resolution in the world, by a factor of 3 to 9. Moreover, EST will be equipped with an unprecedented suite of seven imaging spectropolarimeters acquiring simultaneously multidimensional cubes of data in the optical to near-infrared with a high temporal cadence and a data rate of 1-2 PB/day. By achieving also the highest possible polarimetric sensitivity, a factor of 10-100 higher than that at the 4m DKI Solar Telescope (DKIST, USA), combined with the highest spatial resolution, EST will be a unique, cutting-edge research infrastructure to make a breakthrough in understanding how the Sun operates. Thus, EST will assure that the European solar community is top-equipped to tackle both scientific and societal challenges posed by the Sun.

Switzerland has been one of the leading nations in solar physics since the 19th century, when the worldwide-recognized Zurich sunspot number was introduced by Prof. Rudolf Wolf, also known as Wolf number, which still serves a basis for quantifying solar activity and its effects on the terrestrial climate on a multi-century scale. Since the 1990s, the Swiss world-leading ZIMPOL technology for high-precision polarimetry with the sensitivity down to a few parts per million, developed by Prof. Jan Stenflo, has led to the discovery of hidden solar magnetism. It has been further employed for breakthrough studies of exoplanets at the ESO VLT facility and also for developing new drugs in biopharmaceutics. A pioneering space experiment by Prof. Johannes Geiss for solar wind studies, deployed on the Moon during the NASA Apollo program, has laid a foundation for multi-messenger solar research from space and ground. The growing appreciation of the importance of solar physics for astrophysics, fundamental particle and plasma physics, Earth and climate science, and technology protection from space weather has led to strengthening Swiss solar research through new professorships in solar physics at ETHZ (2019), USI (2022) and UNIBE (2023), and emerging new synergetic research groups at other universities. Furthermore, consolidation of solar research in Switzerland has led to the recommendation for Swiss participation in the EST endorsed by the SCNAT Astronomy Community Roadmap (updated in 2024).