Terrestrial planets are complex systems. Their evolution is dependent on a wide array of different mechanisms and how they interact together. The aim of this session is to emphasize the importance of coupling between different layers of the terrestrial planets and
feedback processes. For example, surface conditions are dependent on atmosphere composition, which results from early and on-going degassing, atmospheric losses and chemistry, and chemical reactions with the surface. In turn, surface conditions can affect the
habitability of the planet. Changes in surface temperature affect surface alteration processes as well as volatile exchanges and might even govern the tectonic regime.
We welcome contributions focused on a single terrestrial body as well as from comparative planetology. Both solar system bodies and exoplanets studies are covered. This session will bring together scientists from a wide range of domains and examine how they can affect planetary evolution. Targeted disciplines include mantle dynamics, planetary structure and composition, tectonic regimes, geomagnetism, volcanism, surface interaction/erosion, atmospheric sciences, volatile cycling, climate and habitability.

The solar system terrestrial planets, and especially the Earth, provide the best opportunity to learn about the basic physical principles of rocky planets, which can then be applied to the evolution of exoplanets and their atmospheres. Similarly, knowledge of the diversity and properties of exoplanetary systems can provide important information about the formation and evolution of our own solar system. In this session, we will focus on general discussions of exoplanetary science, and especially the application of solar system based knowledge to exoplanets and understanding how the Earth can be understood in the exoplanetary context. Of particular interest are studies of atmospheric evolution due to surface-atmosphere interactions and atmospheric losses to space, as well as interactions between stars and planets. Topics include recent advances in observations of (exo)planets lying in the habitable zone, model studies calculating the habitable zone boundaries, factors affecting habitability including atmospheric processes (e.g. outgassing, escape), high energy particles, remote biosignatures and their spectra, planned missions such as JWST, PLATO, E-ELT, LUVOIR, HABEX and ELF and their impact on our knowledge of exoplanetary habitability.

The InSight mission to Mars landed in Elysium Planitia on November 26. InSight's scientific objective is the study of the Martian interior using two seismometers, a heat flow probe and geodetical measurements. Auxiliary instruments will collect meteorological and magnetic data for at least one Martian year.
This session provides initial results from Mars, status reports of instrument deployment and relevant pre-landing science.

The Open Session on Moon, Mars, Mercury, Venus as terrestrial planets systems aims at presenting highlights of relevant recent results through observations, modelling, laboratory and theory. Key research questions concerning the surface, subsurface, interior and their evolution will be discussed, as well as instruments and techniques from Earth and space.
Review talks on specific topics will be accepted on the basis of invitation by the conveners. Please contact the conveners if you have a topic that may be suitable for a review talk.
The session is open to all branches of terrestrial planets systems geosciences, and is intended as an open forum and discussion between their diverse experts and Earth geoscientists.