Embrace Space
Contents |
Abstract
SOTERIA, a FP7 Space Science project, aims at improving our understanding of the space weather phenomena through collaboration between experts in different fields of solar, space and geophysics. The main goal is to make better use of existing data and provide better databases, which will go beyond the present state-of-the-art in regard to details, time-resolution and improved methods of accessing it. We live in an era when the concept of environment is enormously extended: it is not bound to the accessible terrestrial sites, oceans and atmosphere, but it also comprises the extraterrestrial environment including the Sun. What we observe in this expanded and dynamic environment is called Space Weather. Influences of the Sun on the Earth come through the solar spectrum of radiation, which provides us with light and heat, and through other changing features of the solar activity. Some of the most important and impressive phenomena of the solar activity are shown in the figures below depicting sunspots (regions of intense magnetic fields on the solar surface) and coronal mass ejections (CMEs). CMEs carry tremendous amounts of plasma and energy through the solar system, and those which hit the Earth can, in some cases, lead to dramatic consequences. When a CME reaches the Earth, complex series of events in the magnetosphere and ionosphere are triggered, with effects down to the lower atmosphere and on the ground. The studies conducted by SOTERIA involve the analysis and processing of the relevant data from 18 satellites, including several ESA and other European satellites. The study is complemented by a large set of data from European ground-based observatories. SOTERIA includes also considerable effort in utilizing and developing theoretical and simulation models for interpreting the space weather data.
Institutions
The team of the SOTERIA project is coordinated by Giovanni Lapenta of the Katholieke Universiteit Leuven (contact: giovanni.lapenta@wis.kuleuven.be) and includes scientists from institutions in 8 EU countries (Belgium, Denmark, Germany, Austria, Hungary, France, Poland, Finland) and in 3 non-EU countries (Switzerland, Croatia and Russia). The institutions involved are: Katholieke Universiteit Leuven (Coordinator), Universitaet Graz, Schweizerisches Forschungsinstitut für Hochgebirgsklima und Medizin in Davos, Konkoly Observatory, Centre National de la Recherche Scientifique, Koninklijke Sterrenwacht van Belgie, Observatoire de Paris, Space Research Centre, Polish Academy of Sciences, KFKI Research Institute for Particle and Nuclear Physics, Technical University of Denmark, University of Oulu, Georg-August-Universität Göttingen Stiftung Öffentlichen Rechts, Hvar Observatory (Faculty of Geodesy, University of Zagreb), Noveltis Sas, P.N. Lebedev Physical Institute and Informatique Electromagnetisme Electronique Analyse numérique. Full information about the partners and contact information is available on the web site for SOTERIA: www.soteria-space.eu.
Work Programme and Progress
The activities of SOTERIA cover all aspects of the complex processes of space weather in the Sun-Earth connection. The work is organised into 6 work packages (WP):
- WP1: Management.
- WP2: Photosphere and Chromosphere. Starting at the source of the space weather events, the first activity area focuses on the solar photosphere and chromosphere, that are the lowest visible strata of the Sun. The activities developing there are largely determined by what happens under the visible surface, in the interior of the Sun, an area that can currently be explored by helioseismology, a discipline that uses wave activities on the visible surface to detect the underlying structures (similar in principle to the seismology studies done on the Earth for example to detect underground oil reservoirs). SOTERIA collects all the available type of information on the photospheric and chromospheric features of the Sun relevant to space weather. Global changes in the solar activity are characterized by an 11-year cycle. The last cycle has finished recently with its lowest level of activity, and now the new cycle is to begin with an increasingly active phase coming, making the study of space weather even more urgent. Significant puzzlement is currently stirring the community due to the apparent delay in the start of the next phase of increased solar activity, an issue where the historic data collected as part of the SOTERIA project will prove valuable.
- WP3: Solar Corona. The next layer of the solar atmosphere is the corona, visible by the unaided eye during solar eclipses as a crown around the Sun, giving it its name. SOTERIA focuses on bringing to bear the full range of observational tools on the ground and on satellites, including new and planned missions, and of theoretical and simulation tools to advance our ability to understand and predict the dynamic processes of the solar corona, such as the streamers, the flares and the eruptive evolution of solar arcades leading to the so-called CME, coronal mass ejection.
- WP4: Heliospheric Evolution. The solar wind emanating from the Sun carries with it the solar magnetic field and the disturbances caused by the dynamic events on the Sun. The interaction of this complex medium with the planets and especially of course with the Earth is at the core of the study of space weather. The SOTERIA project uses dedicated existing tools, observational and theoretical, to understand this interaction. A catalogue of events covering some of the most common and most interesting occurrences in the space weather is created and a large collaborative effort is made to investigate with all tools available (some of which are in collaboration with American institutions, such as the Community Coordinated Modelling Center of NASA) and by all teams with expertise in this field within SOTERIA. But we also are developing new tools to harness the expertise of some SOTERIA partners in other areas of environmental forecasting (such as the meteorological predictions or the ocean modelling). We are developing a new statistical approach to couple observational data into theoretical simulations (the so-called data assimilation) to improve the predictive capability.
- WP5: Irradiance. Of course the solar influence on the Earth and space is not limited to the solar wind, also the light comes from the Sun! An accurate estimation of the effects of solar events and natural solar cycles is key in our understanding of the Sun-Earth connection, with implications also for the complete understanding of the mechanisms constraining the climate. In SOTERIA, we focus on the variability and the origin of the UltraViolet radiation, which is likely to play a major role in the Sun-climate connection, and also develop models to understand its impact on the upper atmosphere.
- WP6: Dissemination. The main goal is to provide better databases, which go beyond the present state-of-the-art in regard to details, time-resolution and improved methods of accessing it. The complete data coverage of Soteria can be found on the Soteria wiki: www.soteriaspace.eu/wiki/index.php/WP6_VO_Action_Plan. A key aspect of the dissemination activity is related with the Soteria Virtual Observatories (VO) named SODA (Soteria Data Archive), available from the SOTERIA web page. With the start of the HELIO FP7 network Soteria will seek further integration with the HELIO's VO, an activity further promoted by the creation of a specific infrastructure funded by the EC-FP7 project CASSIS.
Finally SOTERIA puts the largest emphasis on making all the models and all the observations described above available not only in their raw format but in a more organized common frame that maximizes the value of data previously scattered and presented incoherently. As part of this effort, SOTERIA does not only rely on state of the art internet-based software tools (including both software tools developed by the USA research efforts and by other European efforts such as the FP7 project HELIO) but will also organize outreach for the general public and training for scientists, in collaboration with other European efforts, funded by COST and international institutions such as the UNESCO International Center for Theoretical Physics, targeting especially to reach young scientists in developing countries. The Soteria partners give also great importance to collaborations outside the network. Soteria has established strong ties with outside partners in the pursuit of better modeling and forecasting capabilites: with the team working on NASA's Magnetospheric Multiscale Mission (MMS) mission at the University of Colorado in Boulder (USA), with the NOAA Space Weather Prediction Center also in Boulder and with the NASA Community Coordinated Modelling Center (USA) that hosts a special section on the Soteria results. A wide and fine mesh of additional collaboration extends from each node of Soteria to involve countless personal and collective collaborations that are too numerous to be reported here.
Example of Results
The results of Soteria are vastly larger than what can be reported here. The interested reader is referred to the Soteria web page for more details. We summarise here three main results in the form of three figures. Soteria has contributed to improving our understanding of origins, propagation and impact of space weather events. Soteria monitors the evolution of the Sun, of the interplanetary space and the Earth space environment with state of the art observational tools on the ground and in space. The Sun’s surface (photosphere) is far from being uniform and steady but rather is a very dynamic swith the most prominent features being Sunspots, shown in Figure 1, obtained from ground-based observations from the Royal Observatory in Brussel. The active regions are the source of major space weather storms, including solar flares and coronal mass ejections that produce highly energetic particles. Figure 2 reports one of these active regions observed by the mission Proba2, one of the most important components of Soteria. Soteria has developed many new results, models and simulation that led to better understanding and prediction of the formation, evolution and propagation to the Earth of these space storms. SOTERIA includes also a considerable effort in utilizing the existing and developing improved theoretical and simulation models for interpreting the space weather data. As an example of the modelling activities, Fig.3 shows the simulation of one region of plasma formed in Sun atmosphere (the solar corona) and propagating towards the Earth. In this process enormous amounts of energy and matter are released with dangerous effects for technology and humans in space. In the case considered a flux rope is formed and is subsequently rendered unstable by the kink instability.
Conclusion
Soteria has concluded its second year of operation and has commenced its third and final year. All the tasks planned for the first two years have been achieved and the work is well underway to reach in time and even beyond the original expectations all the goals that were set for the project. But in the opinion of the Consortium, the success of Soteria, one of the first FP7 space projects to start and the very first space weather-related project ever funded by the EC reach far beyond the technical area. Soteria has succeeded to bring together in a spirit of generous collaboration and even friendship 16 groups and institutions from different countries far from each other and in many case with no previous background of collaboration with each other. Soteria is building a legacy of technical excellence and of better understanding of space weather processes that is leading already to better forecasting tools. And Soteria has formed a network of expert people and state of the art infrastructures upon which Europe can build its future in space weather research.
Figures Captions
Figure 1: Major sunspot group passing central meridian: this image shows an active Sun, only two years after the last maximum of activity, with a major sunspot group passing central meridian. This whole-disk CCD image was taken on Aug. 17, 2002 with the Uccle solar telescopes (ROB, Brussels), one of the ground-based synoptic instruments that will support Work Package 2 of the SOTERIA project.
Figure 2: Close-up view of an active region observed by Proba-2’s SWAP instrument on 3 April 2010. This eruption caused vast amounts of charged particles that reached the Earth the following Monday, 5 April. Proba2 (proba2.oma.be) is a key contributor to the Soteria project.
Figure 3: Simulation of magnetic reconnection, the process of magnetic field annihilation and energy release into the space environment. A complete list of the modelling tools and efforts can be found on the Soteria wiki: www.soteria-space.eu/wiki/index.php/Modelling and on the Data Assimilation menu on the main Soteria web page www.soteria-space.eu
