Are you working on a research project which would benefit from collaborating with an ISSI staff member, with other ISSI visitors, or with researchers nearby in Switzerland?
The ISSI Visiting Scientist programme provides funding for short research visits to conduct research related to data from space missions. Our support consists of the provision of office space at ISSI, plus accommodation and a per diem for the duration of the research visit.
What have White Dwarfs, Neutron Stars, and Black Holes in common? – Accretion disks! For a Swiss who has stirred cheese in multiple occasions and settings, a direct comparison to fork-induced cheese swirls seems obvious. As Alexandra Veledina from University of Turku in Finland points out, the spinning matter of the two might look similar but the physics involved are fundamentally different. Veledina was one of the lead conveners of the ISSI Workshop on Accretion Disks bringing together more than thirty international experts to discuss and sharpen our understanding about them that we developed over the past fifty years.
Online Seminar with Louise Harra
(PMOD/WRC, Davos & ETH Zurich, Switzerland)
The instruments measure the solar wind as it flows past the spacecraft as well as the sources of the wind across the electromagnetic spectrum. A scientific focus has been on understanding the small-scale jets and brightenings that can feed into the solar wind, as well as the larger scale eruptions now that the solar activity cycle is reaching its peak.
Farewell to Our Long-Term Assistant to the Executive Director, Silvia Wenger.
In response to the 2024 call for International Teams, thirty-one projects have been selected by the ISSI Science Committee.
International experts converge to explore the role of Earth Observation in enhancing blue carbon ecosystems for climate change mitigation.
Online Seminar with Amy Simon (NASA, GSFC, USA)
In September 2023, NASA’s OSIRIS-REx returned an amazing 121 grams of regolith from near-Earth asteroid (101955) Bennu. To successfully collect the sample, the mission had to carefully navigate the microgravity environment while also collecting important information about Bennu’s surface. These data provided the high-resolution mapping of the surface that enabled autonomous natural feature tracking during sample collection, while also collecting surface composition information.
The current state of Venus is the result of the cumulative effects of many processes from the planet’s formation, and its magma ocean phase up to present-day. Venus’s interior thermal evolution, volcanic, tectonic and outgassing history, as well as interaction with the atmosphere have left clues to piece back together what made Earth and Venus evolve differently. Therefore, due to its position at the inner edge of the Solar System habitable zone (HZ), Venus evolution through time provides insights on surface habitability of rocky exoplanets.
Mysterious happenings are reported from within the International Space Science Institute in Bern, Switzerland.
Online Seminar with Tilman Spohn (DLR, Berlin, Germany)
ISSI’s Game Changers online seminar series was launched during the first Covid-19-related lockdown in summer 2020 to help keep the community together. Up until this 100th webinar, the series has covered a wide range of topics, from climate change on Earth to life in the universe and the Big Bang.
2024 Caroline Herschel Medal
The International Space Science Institute (ISSI) in Bern, Switzerland, invites applications for a Discipline Scientist in the areas of
1) Exoplanet Sciences
2) Planetary Science and
3) Climate Science
ISSI is currently witnessing a vibrant exchange of ideas as experts from across the globe are convening for the inaugural day of the “Chronology of the Very Early Universe According to JWST: The First Billion Years” workshop.
Online Seminar with Roberto Maiolino (Cambridge University, UK)
The James Webb Space Telescope is revolutionising most areas of astrophysics. One of the most exciting and puzzling findings has been the discovery of a large population of massive black holes within the first billion years after the Big Bang.
The Sun often produces eruptive events on different energetic and temporal scales. It might, however, also produce events, so-called extreme solar events, whose energy could be orders of magnitude greater than anything we have observed during recent decades. But what is an extreme solar event? How strong can they be and how often do they occur?
Digital twin technologies – already established in engineering – are becoming increasingly interesting for applications in Earth sciences. Digital twins offer effective tools for dealing with the dramatic impacts of climate change and extremes on our society. They allow exploring the vast amounts of data produced by numerical models and Earth observations to identify causes and effects of environmental change on water, food, energy and health management, and for finding pathways for a more sustainable future. The enormous computing and data handling challenges for Earth-system twins can only be overcome by substantial investments in super-computing and machine learning. These are addressed by the European Commission flagship activity Destination Earth (DestinE). DestinE was launched in 2021 with a projected lifetime of 7-10 years and is implemented by the European Space Agency (ESA), the European Centre for Medium-Range Weather Forecasts (ECMWF) and the European Organisation for the Exploitation of Meteorological Satellites (EUMETSAT). The project is entering its 2nd phase in mid 2024 and is already delivering first examples of digital-twin technology to selected users.
The Earth’s atmosphere and ocean are in the focus of Professor Weiqing Han, who is affiliated with the University of Colorado and a former ‘Johannes Geiss Fellow’ at ISSI Bern. Her focus is predominantly on the dynamics of our evolving climate across intra-seasonal to decadal time frames. Important facets of her work encompass ocean dynamics, regional sea-level fluctuations, climate variability, and the intricate interplay between the atmosphere and the ocean. Below, Professor Han provides a synopsis of her latest publications arising from her time as an ISSI fellow.
The recent conference, “The Economics and Law of Space-Based Commerce,” convened here in Bern, Switzerland, brought together key stakeholders and researchers from diverse fields, including economics, law, politics, and space sciences. The event tackled pressing questions surrounding the governance framework for private actors in space commerce.
We are now more than a full year into the era of JWST, NASA’s flagship observatory and successor to the Hubble Space Telescope. Exoplanet characterization has historically been dominated by space-based facilities, and the new infrared capabilities of JWST are uncovering the atmospheres of exoplanets in an unprecedented way. The chemical signatures of planets are being actively probed and detected, with an array of new chemical species now detectable including oxygen, carbon and nitrogen-bering molecules. This opens up spectral constrains to the rich atmospheric chemistry ongoing in a wide range of planetary types, temperatures, and metallicities. In this talk, the speaker will discuss some of the outstanding questions in the exoplanet field and how the atmospheric chemistry can help address these questions. He will also present new transit and phase curve results from ongoing JWST programs, including a Neptune and Jupiter mass planet discussing the implications of the chemistry and atmospheric physics of these planets.
The dynamic connections between space weather and weather in Earth’s lower atmosphere was the target of last week’s ISSI workshop. This gathering, between leading experts in space, Earth observation and atmospheric science, delved into the intricate physical interplay shaping our planet’s weather and climate.
ISSI Forum sparks breakthrough guidance for remote sensing collaborations to monitor climate tipping points
In a novel cross-disciplinary effort, the ISSI Team around Erika Palmerio and David Barnes is revolutionizing our understanding of Coronal Mass Ejections (CMEs), powerful solar eruptions with significant space weather impacts on Earth. Focusing on the often-overlooked tomography technique, the team utilizes state-of-the-art magnetohydrodynamic simulations and synthetic white-light data to overcome observational limitations. By placing virtual spacecraft strategically, they generate synthetic images, reconstructing CME structures through discrete tomography.
The findings based on their modelling reveal a complex, irregular front in contrast to traditional assumptions. The team aims to evaluate the impact of 3D reconstructions on space weather predictions, comparing them with conventional forward-modelling techniques. With plans to extend analyses to heliospheric imagery, their work promises groundbreaking insights into CME behavior and improved forecasting methods. Stay tuned for further revelations from this innovative endeavor tackled at ISSI Bern!
See the full team report here: “Tomographic Inversion of Synthetic White-Light Images: Advancing Our Understanding of CMEs in 3D“
The standard cosmological model states that massive galaxies contain a large fraction of dark matter. Dark matter is a transparent substance that does not interact through regular baryonic matter and is only detected through its gravitational pull over the stars and the gas.
Computer simulations of the universe have been in common use since the 1980s, and are now a vital tool in helping us interpret data from increasingly powerful telescopes. Amongst other things, simulations have helped establish the case for dark matter and dark energy, and have been key to creating a broad consensus around the idea that galaxies start small and grow over time through merging. The speaker reviews in outline how these simulations work, and highlight that a key difficulty in understanding their results is to untangle cause and effect. For example, the observed diversity of different galaxy sizes, shapes and colours can be reproduced in a statistical sense, but there is still considerable uncertainty around which causal processes give rise to this diversity. The speaker explains how exerting careful experimentation with the initial conditions for our simulations, which represent conditions shortly after the ‘big bang’, we can start to address these uncertainties. We call this technique ‘genetic modification’, since it loosely corresponds to controlling the genes of our virtual galaxies, to see how the galaxies mature and develop in response. This in turn helps to build a more complete physical picture of how galaxies mature over time, with carefully quantified uncertainties. The speaker discusses how such efforts are vital to making sense of new observations from cutting-edge and future facilities like Gaia, JWST, ELT, SKA and LISA.
Sandra Chapman is the Johannes Geiss Fellow 2023 and is a plasma physicist working on problems in astrophysics and in the laboratory. She is currently Professor of Physics and Director of the Centre for Fusion, Space and Astrophysics at the University of Warwick and adjunct Professor at UIT.
The International Space Science Institute ISSI is proud to announce Prof. Michael R. Meyer (University of Michigan, USA) as the Johannes Geiss Fellow 2024.
The International Space Science Institute is now an associated partner in the research network of the Virtual Alpine Observatory (VAO).
Pro ISSI Talk with Dr. Antonella Nota
The lunar surface allows a unique way forward, to go well beyond current limits in astronomy and cosmology. The far side provides a unique radio-quiet environment for probing the dark ages via 21 cm interferometry to seek elusive clues on the building blocks of the galaxies and the nature of inflation. Optical interferometers will eventually provide up to a few microarsecond imaging of the nearest exoplanets. Far-infrared telescopes in cold and dark polar craters will probe the cosmic microwave background radiation back to the first months of the Big Bang.
Volume 85 in the Space Sciences Series of ISSI
During the recent decades, space missions (e.g., CHAMP, GOCE, GRACE and Swarm) have been developed by space agencies in Europe and the USA to measure the Earth’s gravity and magnetic fields and their spatio-temporal variations. These successful missions have already provided a wealth of groundbreaking results about the permanent and time-variable gravity and magnetic fields of the Earth.
Satellite gravimetry missions such as the on-going GRACE Follow-On (FO) mission, the planned GRACE-FO continuation mission as well as a Next Generation Gravity Mission (NGGM) that will form together with the GRACE-FO continuation mission the Mass-change and Geosciences International Constellation (MAGIC), are unique observing systems to measure the tiny variations of the Earth’s gravity field. Time-variable gravity derived by satellite gravimetry provides integrative measures of Terrestrial Water Storage (TWS) variations on a regional to global scale. Given the large interest of the scientific community to understand the processes of changes in TWS, comprising all the water storage on the Earth’s continental areas in frozen and liquid state, including ice caps, glaciers, snow cover, soil moisture, groundwater and the storage in surface water bodies and the interaction with ocean mass and sea level, TWS was adopted as a new Essential Climate Variable (ECV) in the implementation plan 2022 of the Global Climate Observing System (GCOS).
We have previously expressed ISSI’s concern about the invasion of Ukraine and the resulting humanitarian crisis. The need to maintain science as a platform for dialogue even in times of conflict has become more prominent. As this war continues and other tensions rise around the world, it seems more important than ever to maintain institutions where such peaceful and constructive dialogue can take place. Science is a universal language that knows no geographical or political boundaries, nor boundaries related to race, gender or sexual orientation.
ISSI provides an open and neutral environment where such open and free discussions about Space and Earth Science, and related fields can take place. Dialogue between scientists promotes not only better science, but also a better mutual understanding among people of different origins and cultures. At ISSI we like to think of this as our own small contribution to a better world.
The Team at ISSI and Willy Benz, chair of the Board of Trustees
This workshop will focus on the economics and governance of commercialisation in outer space. It will look at the applicability of economic concepts, the concepts of international economic law, and the concepts of economic governance to space-based commerce.
ISSI is pleased to announce that Dr. Rumi Nakamura and Prof. Geraint Jones have been appointed as Discipline Scientists as of 1st July 2023. We welcome two outstanding additions to the ISSI Team: Plasma Discipline Scientist Dr. Rumi Nakamura, and Planetary Discipline Scientist Prof. Geraint Jones. Not only Discipline Scientists provide scientific expertise that is complementary to the current ISSI portfolio, but, most important, they are ISSI Ambassadors with their unique communities. As such, they will channel ideas and develop scientific initiatives that will best serve their community, while at the same time explore ways to identify how best ISSI can advance the scientific discourse in their respective fields.
Last July scientists and journalists gathered at ISSI to celebrate the unveiling of the first JWST images and spectra. On this occasion Willy Benz, the new chair of ISSI’s BoT, anticipated that JWST would be an observatory that everyone will want to use. The ISSI community is certainly no exception in this respect, with at least two ISSI International Teams securing JWST observing time this spring.
Global sea level and extreme ocean events are rising due to human-caused climate change. The amount of rise in sea level and number of increase in extreme events, however, vary greatly from region to region and they also change over time. To fully understand these changes and thus build the capability of predicting when and where they may occur in the future, we must also consider naturally occurring climate variability.
Happy summer! Hope you are all surviving the sweltering heat and taking some well deserved rest from the hectic winter activities. At ISSI, we are still working at full capacity, catching up from the pandemic hiatus: teams are visiting, workshops are being held, working groups are coming back, totally immersed in discussing, debating, moving science forward. It is a pleasure to see, finally, the teams meeting in person, but with the added bonus that remote access has become a welcome reality to allow fully inclusive participation, and the technology upgrades have made that addition possible and smooth.
Welcome to ISSI, the International Space Science Institute
As Earth’s energy source and a variable star, the Sun has been credited over the past century with causing climate change that is a significant fraction of industrial-era warming… or so small as to be undetectable. Now, with more than forty years of space-based observations of solar irradiance and multiple geophysical quantities, and extensive advances in modelling solar irradiance and terrestrial variability, we can clarify with greater certainty the extent to which the Sun alters Earth’s environment, especially since 1850. This talk summarizes current observational evidence for the Sun’s role in global climate change and ozone-depletion recovery, and discusses the scientific (and societal) consequences of faulty detection and attribution.
The Hubble Space Telescope has been called the most productive scientific instrument in human history. Launched in 1990, the telescope has performed observations which have measured the age of the Universe, confirmed the existence of black holes, discovered the accelerating Universe, and amazed the general public. On Christmas day in 2021 the James Webb Space Telescope (JWST) was launched into space after decades of development. JWST was designed to extend the view of Hubble in regions of the cosmos Hubble can’t penetrate. JWST is exceeding the grand expectations of its ability to unravel the mysteries of the Universe. Join Astronaut/Astrophysicist John Grunsfeld as he takes us through the stories of Hubble and Webb.
The DART (NASA) and Hera (ESA) missions offer the first fully documented asteroid deflection test based on the kinetic impactor technique, allowing us to check and potentially validate our impact numerical models at the real scale of an asteroids. DART succesfully tackled the challenge to deflect the small moon, called Dimorphos, of the binary asteroid Didymos on September 26th, 2022, causing a decrease of the orbital period of Dimorphos around its primary. But many questions remain that will be answered by the Hera mission. Moreover, images sent by space missions to asteroids reveal that these objects are not simple rocks in space but very complex small geological world, whose response to external actions in their low gravity environment challenges our intuition. What did we learn from past missions, what are the challenges, the surprises and the remaining uncertainties? How will Hera measure the outcome of the DART impact and the properties of the asteroid? This presentation will address these questions that are not only relevant for planetary defense but also for the scientific understanding of those small worlds, which are the remnants of the bricks that formed our planets, and of the impact process, which plays a major role in all phase of our Solar System history.
“Do there exist many worlds, or is there but a single world? This is one of the most noble and exalted questions in the study of Nature.”
Albertus Magnus (circa 1200–1280)
Are there other worlds in the universe? Does life exist elsewhere in the cosmos? The technology of our time has made it possible to transform this dream of antiquity into a fascinating field of current astrophysics.
Thirty International Teams have been selected by the ISSI Science Committee for implementation from the proposals received in response to the 2023 call.
NASA interest in climate change goes back decades, and the now 50-year long record of remote sensing has provided clear evidence of ongoing change, as well as process-based information that inform the climate models that help us explain what is happening (and what will likely happen in the future). This talk reviews the highlights of NASA’s work in this area across multiple methods as well as some of the ongoing challenges.
The Earth’s magnetosphere shields our planet from hazardous space weather effects caused by solar disturbances and energetic particles. However, the global structure of the magnetosphere is still extremely difficult to describe. Major challenges include the scarcity of data sets, as well as the breadth of physical processes that need to be taken into account. Our ISSI Team explores various approaches that help to mitigate these challenges. Recent publications from our ISSI Team provide new insights into how to extract information about global magnetospheric and ionospheric structures, and how to combine global data analysis and global modeling in meaningful ways. The new results suggest potentially transformative ways to work with global datasets, develop new global models, and improve the accuracy of the current global models.
Earth’s magnetic environment is filled with a symphony of sound that we cannot hear. All around our planet, ultralow-frequency waves compose a cacophonous operetta portraying the dramatic relationship between Earth and the Sun. Now, a new citizen science project called HARP – or Heliophysics Audified: Resonances in Plasmas – has turned those once-unheard waves into audible whistles, crunches, and whooshes. Early tests have already made surprising finds, and citizen scientists can join the journey of sonic space exploration to decipher the cosmic vibrations that help sing the song of the Sun and Earth.
In the blockbuster science fiction movie “Interstellar” (Warning: spoiler alert!), a team of intrepid astronauts set out to explore a system of planets orbiting a supermassive black hole named Gargantua, searching for a world that may be conducive to hosting human life. With Kip Thorne as science advisor, the film legitimately boasts a relatively high level of scientific accuracy, yet is still restricted by Hollywood sensitivities and limitations. In this talk, we will discuss a number of additional effects that may be important in determining the (un)inhabitable environment of a planet orbiting close to a giant, accreting black hole like Gargantua. In doing so, we hope to reach a greater understanding of the fascinating physics governing accretion, relativity, astrobiology, dark matter, and yes, even gravitational waves.
The magnetic field is fundamental to solar activity and shapes the interplanetary environment, as shown by the full three-dimensional monitoring of the heliosphere provided by measurements from many past and present interplanetary and remote sensing spacecraft. Magnetic fields are also the source for coronal heating and the very existence of the solar wind; produced by the sun’s dynamo and emerging into the corona, magnetic fields become a conduit for waves, act to store energy, and then propel plasma into the Heliosphere in the form of Coronal Mass Ejections (CMEs). Magnetic fields are also at the heart of the generation and acceleration of Solar Energetic Particle (SEPs) that modify the space weather environment of the Earth and other planets.
Parker Solar Probe (PSP)’s launch in 2018, followed by Solar Orbiter (SO)’s launch in February 2020 have opened a new window in the exploration of solar magnetic activity and the origin of the Heliosphere. The first direct measurements of the plasma in the closest atmosphere of our star have already produced significant surprises, including the presence of folds in the magnetic field called switchbacks that come in patches, the prevalence of the bursty phenomenon known as magnetic reconnection together with turbulence in the outer corona and accelerating solar wind.
The observation by NASA’s Parker Solar Probe mission of very strong magnetic field fluctuations in the inner heliosphere, leading to strong deflections locally reversing the direction of the field itself, called switchbacks, has attracted considerable attention from the heliophysics and space physics communities.
It is with great sorrow that we have learned of the passing of Götz Paschmann on the 23rd of February, at the age of 84.
Extreme geomagnetic storms can have significant impact on a wide range of technologies and a particular challenge is quantifying their occurrence likelihood since they are rare events. Geomagnetic storm occurrence varies with the solar cycle and each cycle has a unique amplitude and duration. Whilst there are comprehensive high fidelity space weather relevant observations over the last four to five solar cycles, observations that extend over multiple cycles are more limited. Nevertheless, historical ground magnetic observations over the last 150 years can be used to quantify space weather risk. They can be combined with the sunspot record to construct a uniform ‘clock’ for space weather activity which reveals a fast switch-on (and off) between the relatively quiet conditions around solar minima, and more active conditions around solar maxima. The clock provides a framework to predict the switch-on and off times, imperative since some of the most extreme events have occurred just after the switch-on.
Report from the ISSI Team #447 Cold Plasma of Ionospheric Origin at the Earth’s Magnetosphere led by Sergio Toledo-Redondo (ES)
Above the neutral atmosphere, space is filled with charged particles, which are tied to the Earth’s magnetic field. The particles come from two sources, the solar wind and the Earth’s upper atmosphere. Most of the solar wind particles are deflected by the Earth´s magnetic field, but some can penetrate into near-Earth space. The ionized layer of the upper atmosphere is continuously ejecting particles into space, which have low energies and are difficult to measure. We investigate the relative importance of the two charged particle sources for the dynamics of plasma processes in near-Earth space. In particular, we consider the effects of these sources in magnetic reconnection.
In the last few years machine learning techniques have proven capable of forecasting space weather events with a much higher accuracy with respect to long-used traditional empirical and physics-based models. Even though very few operational models are currently empowered by machine learning, it appears to be unavoidable that the community will embrace in the near future such powerful techniques. Indeed, it is hard to imagine the future of space weather without machine learning. Presently, we are moving one step further from the initial ‘early-adopter’ stage, where proof-of-principles models were elaborated and tested, and more consideration is being given to the issues of reliability, uncertainty, and trustworthiness of machine learning models, finding the right balance between physics priors and data-driven discovery. In this talk the speaker presents the state-of-the-art of machine learning applications for space weather problems and discusses a few challenges and opportunities that this field presents to us.
Dear ISSI community,
I am absolutely delighted to have an opportunity to connect with you all and start a dialogue that I hope will continue for many years to come.
After one month on the job as Executive Director, I would like to share with you my first thoughts. In this post-pandemic world, more than ever there is the need for a place where scientists can gather and tackle key scientific questions together. ISSI is such a place: a beautiful institution that advances science by facilitating scientific discourse. Scientists are eager to meet in person, and do what they do best: debate, solve problems, move their field forward. ISSI offers a wonderful location and infrastructure to facilitate that, and continues working at full capacity to satisfy your collective requests. This can only happen thanks to a truly outstanding and dedicated staff, and I am honored to work with them.
Propagation parameters of electromagnetic waves such as amplitude, phase and polarization are impacted when traveling within the ionospheric plasma of the Earth. Related effects can be used on one hand to monitor and study the ionosphere by analysing the changes of measured propagation parameters. On the other hand, space weather impact on the ionosphere may cause unwanted distortions of signal detection in modern ground and space-based radio systems applied in telecommunication, positioning, navigation and remote sensing. After clarifying the main terms, the talk focuses on the discussion of space weather induced changes of the ionospheric plasma and associated impact on radio wave propagation used in diverse applications. Besides ionizing solar radiation and ionospheric plasma dynamics also solar radio bursts may seriously impact the functionality of radio systems via interference.
In the recent years, thanks to Solar System exploration, our knowledge on the interactions between a planetary body and its local space environment, where perturbations of solar or non-solar origin may occur, has been dramatically increased. Our understanding of the so called planetary space weather science is of paramount importance also for getting clues on similar –in their nature– phenomena that evolve in the circum-terrestrial environment, nevertheless, at different temporal and spatial scales. Moreover, determining the properties of radiation environments inside planetary magnetospheres is one of the key challenges of magnetospheric physics research. At the same time, it allows the design and manufacturing of satellites and payloads that are resistant to hazardous environments. In this talk, the speaker will discuss some examples of space weather science approaches, especially in the context of the Outer Solar System exploration. Moreover, the speaker will try to evidence the role of theoretical and/or data-driven modeling during preparation for upcoming exploration missions and discuss some future perspectives.
Satellites in low Earth orbit travel through the uppermost layer of the neutral atmosphere, where their movement is affected by variations in the density and wind. These variations affect the amount of fuel required by active satellites to fulfil their mission, as well as the duration that debris objects remain in space. The number of objects in low Earth orbit has been rapidly increasing. With it, concerns over the long-term sustainability of the use of this region of space have been on the rise as well. The trend in the number of objects is due to the ever increasing relevance of satellite missions to our society, combined with technological developments such as miniaturisation and the rise of mega-constellations. But also in-orbit breakups of rocket stages and satellites have been major contributors. In this talk, the speaker will provide an overview of the physics and technology related to this topic, as well as the ways in which international collaboration will be essential to provide solutions.
It is with great sadness that we have learned that Jean-Pierre Swings passed away Monday January 16, 2023. Jean-Pierre Swings was an emeritus professor of astronomy at the University of Liège, Belgium. His scientific research was related to various fields of astrophysics connected to stars, galaxies, gravitational lensing, and space technologies.
The aurora borealis (to the north, and australis to the south of the Earth) are the most spectacular phenomena of a chain that connects the planet’s upper atmosphere to the solar activity. In this lecture, the speaker addresses the questions they raise: What solar origin ? What interaction between the solar wind and the space environment ? How are they formed? What are they witnessing? Do they exist elsewhere than on Earth? What research is still being done on auroras?
Giant planets and brown dwarfs at an orbital separation great than 5 AU are important puzzle pieces needed for constraining the uncertainties that exist in giant planet formation and evolutionary models that are plagued by a lack of observational constraints. In order to observationally probe this mass-separation parameter space, direct imaging is necessary but faces the difficulty of low detection efficiency. To utilize the power of direct imaging, pre-selecting companion candidates with long-period radial velocities, coupled with astrometry from Hipparcos and Gaia, provide a powerful tool to hunt for the most promising candidates for direct imaging. Not only does this increase the detection efficiency, but this wealth of information removes the degeneracy of unknown orbital parameters, leading to derived dynamical masses which can serve as benchmark objects to test models of formation and evolution. With the recently launched JWST, as well as upcoming facilities like the ELT and the Nancy Grace Roman Space Telescope, observing time is valuable and the strategy of direct imaging needs to be re-defined to pre-select targets and characterize the companions that we do discover.
Report from the ISSI Team #448 “Global study of the transmission of foreshock ULF waves into the magnetosheath and the magnetosphere” led by L. Turc and M. Palmroth
Plasma waves forming in the turbulent foreshock upstream of Earth’s bow shock have long been known to transmit into Earth’s magnetosphere. Yet the exact mechanism allowing their propagation through the shock remained unknown. A recent paper published in Nature Physics, led by Lucile Turc and initiated within the ISSI Team #448, proposes a new scenario to explain the wave transmission.
Report from ISSI Team #472 on Closing The Gap Between Ground Based And In-Situ Observations Of Cometary Dust Activity: Investigating Comet 67P To Gain A Deeper Understanding Of Other Comets led by R. Marschall (FR) & O. Ivanova (SK)
ESA’s Comet Interceptor mission (launch in 2029) will, for the first time, visit a long period or dynamically new comet (LPC/DNC), one the most pristine objects in our Solar System. DNCs have been stored in the outermost part of our planetary system since they formed 4.5 billion years ago. From there, they enter the inner Solar System for the first time to reveal their primitive structure and composition.
Space weather has affected aviation in many ways; effects include short-wave radio disturbance, single-event effects leading to upsets in electronics, Satellite Navigation systems disturbance via scintillation, solar radio burst effects on secondary surveillance radar, increased radiation dose at flight altitudes. In November 2018, a long process involving experts from many countries of the world came to a conclusion when the ICAO Air Navigation Commission and the Council of ICAO, the International Civil Aviation Organization, approved and published provisions in ICAO Annex 3 and guidance material on Space Weather in ICAO Document 10100. The advisories intend to provide the most up to date information on space weather impacts on aviation. The introduction of space weather in the ICAO framework has been a great achievement. What is still outstanding is the development of procedures that are globally standardized on the application of the advisories, as well as the provision of adequate space weather knowledge to pilots, controllers and other aviation personnel. Recent events are used to illustrate this. The talk will be about space weather for aviation: what´s been achieved – and what needs more work.
Human activities have become a dominant force of terrestrial transformations, inducing a clearly observable change of the climate, ubiquitous pollutions of air, soil and water, and an unprecedented decrease of the living. Faced with this situation, the assessment of the environmental footprint of human activities becomes a key instrument to inform sustainability action plans and roadmaps. In this webinar the speaker summarises the current knowledge on the environmental footprint of Space Sciences, explaining its origins and impacts. A particular focus will be placed on the carbon footprint of astronomical research, for which detailed estimates are becoming available. Forecasts for the evolution of the field will be discussed and confronted with the imperative to drastically reduce green house gas emissions over the coming decades. The speaker demonstrates that profound changes are required for making Space Sciences environmentally sustainable.
There is life on Earth thanks to the energy we get from the Sun. But how exactly does the Sun and our space environment result in a habitable climate? Some of the energy we get directly as radiation, some as charged particles from the solar wind and Earth’s magnetosphere. In this seminar, we learn how these two distinct sources influence our atmosphere and what the implications to Earth’s climate are. We particularly focus on the influence of charged particles of solar and magnetospheric origin, a pathway recently included for the first time in the climate simulations informing the Intergovernmental Panel on Climate Change (IPCC).
Solar energetic eruptive processes, such as flares and coronal mass ejections, are relatively well-studied during the past decades of direct observations. Although their maximum strength/energy is not constrained by direct data because of a too-short period of observations, we know that extreme events do occur rarely on the Sun over the last millennia, thanks to cosmogenic-proxy data, and also on sun-like stars, thanks to high-precision stellar photometry. Not only we can estimate their occurrence probability but even reconstruct energy spectra and assess the dramatic terrestrial and societal impacts. However, the nature of such events remains unclear – are they ‘normal’ but just extremely strong solar flares (Black Swans) or do they represent an unknown type of solar events (Dragon Kings)? A summary of the existing pieces of knowledge will be presented along with a try to make a distinction between the Black-swan and Dragon-king scenarios of the extreme events.
In this last year, the Pantheon+ and SH0ES teams released likely our last measurements of the expansion history of the universe. On one hand, constraints from Pantheon+ show a universe consistent with the Lambda-CDM model, where dark energy can be described by a cosmological constant. On the other hand, constraints combining Pantheon+SHOES data find a high value of the Hubble constant, now 5sigma away from the value inferred using Lambda-CDM from measurements of the Cosmic Microwave Background. How can both these statements be true? In this talk, the speaker goes over these separate but overlapping measurements, and discussess how we can have tensions with some parts of the cosmological model but not others. The speaker discusses possible explanations to the Hubble tension, and goes over how other tensions have arisen in cosmology. Finally, the speaker talks about how new telescopes, like the James Webb Space Telescope, can help resolve these controversies.
Studies have shown that stars contain very little baryonic matter and that the majority of the baryons in the universe likely exist in gaseous form. Cool baryons are more easily observed, but what have been seen cannot account for the expected number of baryons produced in the early universe. The lack of understanding of the origin and distribution of “missing baryons” is impeding the progress in completing the picture of baryon cycling in galaxy ecosystems. The bulk of the “missing baryons” may be exist in the form of hot, extended halos around galaxies and/or filamentary structures in the cosmic web; recent observations seem to support such scenarios. However, due to the lack of a sensitive probe, the physical and chemical properties of such hot baryons are poorly measured with existing facilities, but carry critical information on the feedback processes that are deemed critical to galaxy evolution. Theory is far ahead of observation in this area; data are severely lacking. The speaker describes the missing baryon puzzle and provide a personal perspective on how to solve it.
More than three decades ago the late Johannes Geiss started to think about creating a new kind of institute where the space science community could work together. It would be tasked with contributing to a deeper understanding of the results from space research missions, adding value to those results through multi-disciplinary research in an atmosphere of international cooperation. By using his characteristic enthusiasm and perseverance he managed, together with a small group of Swiss colleagues and against all odds, that ISSI could open its doors in 1995 with a workshop on The Heliosphere in the Local Interstellar Medium.
Dark matter is believed to comprise five-sixths of the matter in the universe, and is one of the strongest pieces of evidence for new fundamental physics. But dark matter does not interact directly with light, making it very difficult to detect except by its gravity. It’s described how various properties of dark matter could lead to observable signals, and how we can attempt to identify those signals from telescope observations. The speaker gives examples of cases where possible signals have been seen, but their origin is not yet fully understood. Furthermore, the speaker discusses how solving the puzzle of those observations will advance our understanding of our Galaxy and cosmos, either by revealing properties of dark matter or providing new insights into astrophysics.
Report from the ISSI Team #535 “Unraveling Surges: a joint perspective from numerical models, observations, and machine learning” led by D. Nóbrega-Siverio
A numerical experiment – performed by Daniel Nóbrega Siverio and Fernando Moreno Insertis – has shown for the first time how one of the most abundant structures in the solar atmosphere, the Coronal Bright Points, can be formed, acquire energy, and be disrupted through the action of solar granulation.
When the Sun is observed from space with X-ray or extreme ultraviolet detectors, its atmosphere is seen to be full of roundish bright points with sizes similar to our planet Earth. These Coronal Bright Points (CBPs) are found to be consisted of sets of bright magnetic arcs that confine very hot plasma and emit enormous amounts of energy for hours and even days, typically disappearing after a series of eruptive phenomena.
Report from ISSI Team #469 Using Energetic Electron And Ion Observations To Investigate Solar Wind Structures And Infer Solar Wind Magnetic Field Configurations led by G. Li and L. Wang
Coronal mass ejections (CMEs) represent some of the most energetic processes in the entire solar system. They are often associated with Solar Energetic Particle Events (SEP events) and are major concerns of space weather studies. When CMEs happen, they drive shock waves in front of them and charged particles are accelerated at the shock front through the diffusive shock acceleration mechanism. Protons and ions can be accelerated to the energy beyond 1 GeV/nuc in some of the most energetic SEP events. Understanding how particles are accelerated in these events and how these accelerated particles propagate to the Earth has been a central problem for space plasma physics.
ISSI expresses its deep dismay and concern regarding the invasion of Ukraine by Russia and the resulting grave humanitarian crisis.
ISSI reaffirms its long-standing position that science is a platform for dialogue even in times of profound geopolitical conflict, and therefore a resource on which to capitalize to restore and preserve peace.
ISSI states that our capacity to work collaboratively on global challenges such as climate change and space research is only equal to our capacity to maintain strong collaboration amidst geopolitical turmoil. The isolation and exclusion of important scientific communities is detrimental to all.
ISSI pledges to advance equal participation and collaboration between scientists from all countries in its activities and to adhere to its principle that all of its activities are conducted with the highest ethical standards.
Georges Meylan
President of ISSI Board of Trustees (2015-2023)
for the ISSI BoT, ISSI Directorate, and ISSI Staff
Report from ISSI/ISSI-BJ Team #444 “Chemical Abundances in the ISM: The Litmus Test of Stellar IMF Variations in Galaxies Across Cosmic Time” led by D. Romano and Z.-Y. Zhang
Astronomers have known for a long time that large galaxies grow through accretion and merging of smaller systems. A recent study published in Nature Astronomy demonstrates that this fundamental pattern of structure formation also applies to galactic satellites on small scales. A team of Italian researchers and members of the ISSI/ISSI-BJ Team #444 has discovered an old star cluster in the Large Magellanic Cloud (LMC) whose chemical composition is unambiguously pointing to an external origin.
Report from ISSI Team #415 Understanding the Origins of Problem Geomagnetic Storms led by N.V. Nitta and T. Mulligan
Coronal mass ejections (CMEs) are large eruptions from the Sun that are often powerful drivers of space weather effects at Earth. Being able to predict their behaviour in interplanetary space is one of the main goals of space weather forecasting. However, there is a class of CMEs that are particularly hard to observe and, therefore, forecast. These eruptions are known as “stealth CMEs” and they were first reported by Robbrecht et al. [2009], who used the twin STEREO spacecraft (in orbit around the Sun) that were separated by ~50° in longitude to observe a clear ejection off the solar limb from one perspective, but no corresponding eruptive signatures against the solar disc from the other. The lack of indications that an eruption has occurred makes it particularly challenging to establish whether a CME is Earth-directed, especially when imagery from secondary viewpoints is not available. Nitta & Mulligan [2017] analysed a number of stealth CMEs that, in fact, caused unexpected space weather effects at Earth, also known as “problem geomagnetic storms”.
Report from the ISSI Team #408 Low Frequency Imaging Spectroscopy with LOFAR – New Look at Non-Thermal Processes in the Outer Corona led by E. Kontar
The combination of kinetic simulations with LOFAR telescope observations published in a paper in Nature Astronomy shows that the fine structures are caused by the moving intense clumps of Langmuir waves in a turbulent medium.
Report from the ISSI Team #477 “Radiation Belt Physics From Top To Bottom: Combining Multipoint Satellite Observations And Data Assimilative Models To Determine The Interplay Between Sources And Losses” led by led by J.-F. Ripoll (CEA, France), G. D. Reeves (Los Alamos National Laboratory, USA) & D. L. Turner (Applied Physics Laboratory, USA)
Lightning superbolts are the most powerful and rare lightning events with intense optical emission, first identified from space by the Vela satellites at the end of the 70s. Recently, radio frequency superbolts were geographically localized by the very low frequency (VLF) ground stations of the World-Wide Lightning Location Network (WWLLN). Interestingly, the distribution of superbolt locations and occurrence times was not equivalent to that of ordinary lightning: instead, superbolts were found to occur over oceans and seas at a much higher rate, and more often in winter [Holzworth et al., 2019].
This talk was organised by the Association Pro ISSI and was recorded on March 24, 2021.
Abstract: The Earth is the only planet of the Solar System hosting evolved life. «How to build an habitable planet ?» has led to considerable scientific literature in the recent decades and has strongly motivated research on exoplanets. All along its history the Earth has displayed specific chemical and physical properties, including a relatively stable climate that a played major role in the evolution of living organisms. In this presentation we discuss the physical particularities of planet Earth, such as gravity and magnetic fields, rotation, mantle convection and plate tectonics, volcanism and water cycle, and their impacts on climates and life, from paleo times to present. Today, Homo Sapiens polulation is approaching 8 billions, a factor 8 times larger than 2 centuries ago, and an indirect consequence of fossil energy use and associated technological innovation. However, our present-day world is facing a number of new «Grand Challenges», as summarized by the United Nations (UN) 2030 Agenda for Sustainable Development. By providing invaluable information on the Earth system and its evolution under natural and anthropogenic forcing factors, Earth observation from space has a key role to play for reaching several of the 17 Sustainable Development Goals of the UN 2030 Agenda, in particular those related to current climate change, water resources, land and marine biodiversity and food security.
Bruno Leibundgut (European Southern Observatory (ESO), Garching, Germany) was elected as the Johannes Geiss Fellow 2019. In the following paragraphs he answers a few questions – asked by Lorena Moreira, ISSI Earth Sciences Post Doc – about his scientific work (in pandemic times).
Report from ISSI Team #397 Comet 67P/Churyumov-Gerasimenko Surface Composition as a Playground for Radiative Transfer Modeling and Laboratory Measurements” led by M. Ciarniello
Recent investigations of the surface composition of comet 67P/Churyumov-Gerasimenko, by means of observations provided by the VIRTIS imaging spectrometer onboard the Rosetta mission, revealed the presence of aliphatic organics and ammonium salts, which characterize the ubiquitous 3.2 µm absorption band in the comet’s infrared spectrum.
