The Sun, our closest star, powers life on our planet. The Sun- Earth Connection (SEC) is a fundamental research topic and its understanding is a central challenge of contemporary space physics. The Sun incessantly and intermittently forces the terrestrial and other planetary magnetospheres both with its farreaching magnetic fields and continuous plasma flows (solar wind), and via sudden releases of huge amounts of radiation (solar flares) and expulsions of magnetic flux and plasma in the heliosphere (coronal mass ejections; CMEs). This variable solar forcing is termed Space Weather, in analogy to terrestrial weather. Triggered by solar eruptions, space weather poses a serious safety threat to our space assets (e.g., satellites, astronauts) and to sensitive ground-based activities and infrastructure (e.g., power grids, polar flights of airplanes, GPS-reliant tasks). This is an extremely timely topic of basic science, given:
(i) the comprehensive observational coverage of the various related domains (e.g., Sun, interplanetary medium, Geospace) thanks to an array of recent missions,
(ii) the recent advances in theory and modeling and
(iii) the forthcoming access to the inner heliosphere via novel heliospheric missions (e.g. Solar Orbiter (SO), Solar Probe Plus (SPP), etc.).

Programme
The session combines observations, data analysis, theory, and numerical simulations, to address the following questions:

1. How does the coupling between solar magnetic fields and plasma flows power solar eruptions? (Emergence and evolution of solar magnetic fields, triggering and evolution of solar eruptions, coronal structure, and solar wind formation).
2. How does the solar wind interact with the ejecta and how do the terrestrial and planetary magnetospheres react to the perturbed solar wind? (propagation of CMEs and Solar Energetic Particles in turbulent solar wind plasmas, development of geospace magnetic storms, acceleration of electrons to relativistic energies in the Van Allen radiation belts).
3. Multi-scale observations of the Magnetosphere-Ionosphere- Thermosphere System (new results from the VAP and MMS missions).

Invited speakers

Scientific organisers
Vasilis Archontis, (University of St Andrews, UK)
Ioannis Daglis, (University of Athens, GR)
Spiros Patsourakos, (University of Ioannina, GR)
Angelos Vourlidas, (JHU/APL, USA)

Contact
spatsour @ cc.uoi.gr