Stars and planets form as the end products of a complex chain of mechanisms starting in the galactic interstellar medium. In the course of molecular cloud collapse and disk formation, initial conditions are set for later habitable zones; the ensuing growth of planets and evolution of their atmospheres lead to the large range of planetary environments, some of which may be habitable. The forming and evolving stars themselves play an overwhelming role in controlling the evolution of their environments. Short-wavelength radiation (UV, EUV, X-rays), stellar ionized winds, and high-energy particles play a fundamental role in processing circumstellar material and planetary atmospheres and magnetospheres.

How potentially habitable regions are established is presently rather poorly understood. Apart from the direct starlight allowing for mild climates and liquid water on a planetary surface, many further conditions must be fulfilled and be kept within limits during the violent early years of a star's life that is rather different from what we encounter in the present-day solar system.

To address questions on the formation of habitable environments in young stellar/planetary systems, the Austrian Science Foundation (FWF) approved the Pathways to Habitability project end of 2011 as a large national key project. The project addresses the astrophysical conditions for planetary habitability. It is anticipated to run for 8 years, between 1 March 2012 and 29 February 2020. The project is organized in 7 subprojects (SPs) addressing the following fundamental questions:

  • How does protoplanetary disk gas and dust evolve, form water and organic molecules and transport them to the sites where habitable planets are forming?
  • How does magnetic activity, the ionized wind, high-energy radiation and particles influence the planetary environment and interact with planetary atmospheres?
  • How are upper planetary atmospheres evolving under the influence of stellar radiation and winds in the presence of a protecting magnetosphere?
  • How are dynamics, stellar winds and radiation controlling habitable zones in binary systems?

Our principal goal will thus be to understand the formation and early evolution of habitable environments in young, active stellar surroundings in which high-energy processes and radiation prevail. These studies will reach significantly beyond any presently being conducted, and will strongly link to future observing opportunities with instruments such as the James Webb Space Telescope, ALMA, EChO and others.

 

Organisational scheme of the "Pathways to Habitability" project, showing the major and minor links between the subprojects (SPs). The colors underline the main research directive of the corresponding group.