Solar irradiance is the main external forcing on the terrestrial atmosphere, weather and climate. Although measurements and modeling of the solar irradiance were under close scrutiny during the last decade, the complete picture of solar variability and its impact on climate is still far from being clear. In particular, the secular component of solar variability is poorly understood, mainly because long-term measurements are scarce.

Nevertheless, there is a rich set of observational data of Sun-like stars collected from the ground (i.e. APT measurements at Fairborn Observatory) and space (i.e. Kepler or Corot). Comparisons of solar and stellar data should allow a better understanding of solar and stellar variability at all time scales. This is important for the Earth’s climate and the detectability and habitability of extrasolar planets.

This interdisciplinary session aims at sharing knowledge about solar and stellar variability and its impact on nearby planets. We welcome contributions that cover all aspects related to these topics and will encourage discussions and collaboration between the different communities.

The contributors to this session will be invited to submit their work in a special issue of the international journal Space Weather and Space Climate.