ERC Synergy Grant in Astrophysics

About SUN projects

Understanding the physical mechanisms behind the eruptive activity of the Sun and its stellar twins.

This project has just been funded for six years by a prestigious Synergy grant from the European Research Council (ERC). Four European experts on the Sun and stars, from the Astrophysics Department of CEA-Irfu / UMR AIM in France, the Max Planck Institute for Solar System Research (MPS) in Germany, the University of St Andrews in the United Kingdom and the University of Oslo in Norway, will pool their know-how and knowledge of the dynamics of our star and its twin stars. The objective is to determine over the next six years how the magnetic field is generated inside the Sun and how it creates solar spots on its surface and eruptions in its highly stratified atmosphere. To this end, the team will develop the most advanced complete Sun model using the most powerful supercomputers, known as Exa-scale, and will constrain it with observations from space missions, such as the European Space Agency's (ESA) Solar Orbiter, to be launched in 2020.




MISSION : Despite decades of intense research, most fundamental questions remain unanswered, such as: How does the Sun work? Why does it have a magnetic cycle, blackheads and a dynamic hot atmosphere? "In the Whole Sun project, we want to address these key issues for the first time as a coherent whole.

VISION: Solar activity, with its many manifestations and eruptions of magnetized clouds and particles, has a direct impact on our technological society. Understanding it is therefore a major societal challenge. "The WHOLESUN project is an innovative multidisciplinary approach in solar physics that will lead to successful collaborations in Europe," predicts Professor Eric Priest of the University of St Andrews. Indeed, in recent decades, research in solar physics has focused on studying the structure and dynamics of the interior of the Sun or the solar surface/atmosphere. The objective is to consolidate the studies of these two major solar regions, through strong synergies between the team members, in order to acquire an advanced understanding of their coupling and the Sun. "The detailed study of the (thermo)dynamic and magnetic coupling between the core of the Sun, the solar surface and the highly stratified atmosphere is absolutely essential if we want to address the key and open problems of solar physics" argues Dr. Antoine Strugarek (DAp-AIM) involved in the project.

The WHOLESUN project is made possible by advances in supercomputing. “The project will develop numerical models of the whole Sun that will run on exascale supercomputers that perform a billion billion arithmetic operations per second”, explains Principal Investigator Allan Sacha Brun from CEA Saclay France. The numerical models will be used in combination with observations to tackle many unsolved mysteries in solar physics. For example, it is not known how sunspots are formed, nor what triggers the most energetic solar flares.

Violent solar eruptions throw charged particles and radiation into space. "The origin of all the eruptive phenomena that we observe in the Sun’s atmosphere, however, lies much deeper within our star," explains Professor Laurent Gizon, one of the Principal Investigators of WHOLESUN.

News & seminars




Prof. Laurent Gizon (Principal Investigator)- top left

Dr. Vasilis Archontis (Principal Investigator) - top right

Prof. Mats Carlsson (Principal Investigator) - bottom left

Dr. Allan Sacha Brun (Corresponding Principal Investigator) - bottom right

Preparation of the ERC Synergy oral at the end of August 2018.


Fernando Moreno-Insertis (Co-Investigator)

Teams members



Prof. Laurent Gizon
Dr. A. Birch
Dr. R. Cameron


F. Kupka, Senior Postdoc
(05/01/19 – 06/30/20)
K. Mandal, Postdoc
(11/01/19 - )
D. Fournier, PhD
(10/01/20 -)
C. Goddard, Postdoc
(05/01/19 – 06/01/20)
S. Cloutier, PhD
(01/01/20 - )
Y. Bekki, PhD, Postdoc
(03/01/20 - )

St Andrews


Dr. Vasilis Archontis
Prof. A. Hood


P. Syntelis, Postdoc
(05/01/19 – 10/01/19)
A. Borissov, Postdoc
(09/01/20 - )
G. Chouliaras, PhD
(09/27/20 - )

Oslo University


Prof. Mats Carlsson
Prof. V. Hansteen
Associate Prof. B. Gudiksen


K. Krikova, PhD
(09/01/20 - )
R. Robinson, PhD
(09/23/19 - )
Andrius Popovas, Research Software Engineer
(01/03/2020 - )



Dr. Allan Sacha Brun
Dr. P. Kestener
Associate Prof. M. Browning
Assistant Prof. L. Jouve
Dr. A. Strugarek


Q. Noraz, PhD
(10/08/19 - )
R. Pinto, Senior postdoc
(01/06/20 - )
A. Finley, Postdoc
(12/01/20 - )
M. Delorme, Senior postdoc/HPC researcher



Prof. F. Moreno-Insertis
Dr. M. Collados
Prof. J. Trujillo-Bueno
Dr. E. Khomenko


B. Coronado, PhD, in kind contribution
(11/01/20 - )
D. Nobrega,Postdoc
(03/01/21 - )
Manuel Luna, Senior postdoc, in kind contribution (05/19 - ) .


Solar Research


Scientific Advisory Committee :
Prof. Paul Charbonneau, Prof. Louise, Harra, Prof. Moira Jardine, Prof. Takashi Sekii, Prof. Juri Toomre



Three examples of multi-resolution grids developed with the p4est library: spherical shell with (left panel; r=[0.7,1.8] Rsol) or without (middle; r=[0.5,1] Rsol) a stretched grid to solve for the lower atmosphere and full sphere (right; r=[0,1] Rsol) cases [91]. Comparing the left and middle cases, having a stretched grid above the highly-resolved surface leads to a workload gain of more than 50% overall.



Papers and press releases

Latest WP references

See also :
Strugarek A., Beaudoin P., Charbonneau P., Brun A.S., Do Nascimento Jr J.D. solar and stellar magnetic cycles with nonlinear dynamo simulations", Science (14/07/2017)
Augustson, K., Bruin, A.S., Toomre, J., ApJ 809, 149, (2015)
Gudiksen B., Carlsson, M. et al. A&A, 531,154, (2011)
Brun, A.~S., Miesch, M.~S., Toomre, J., ApJ, 614, 1073-1098 (2004)

UiO news (Published on 19 December 2018)
Press release CEA-CNRS (Published on 25 October 2018 )
Space Daily News (Published on 24 October 2018)
MPG Newsroom (Published on 23 October 2018 )

Public Outreach


magnetic cycle in virtual reality


Spectacular view of the Sun as a whole.




Location Map: Coming at Saclay