Blue Dots

Key science questions

The following have been identified as key science questions for the Formation and Evolution of Planetary Systems theme:

  • Circumstellar disk evolution and Planet formation
    • How are the temporal evolution of circumstellar disks and the formation of planets connected? What is the role of planet-disk interactions on the planetary system formation process?
    • Which roles do host mass and metallicity play?
    • What is the role of the star/planet formation environment (low-mass vs. high-mass star forming regions, clusters)?
    • Which are the conditions that decide about predominance the planet formation scenario: Core accretion vs. Gravitational instability?
    • Are there fundamental differences in the planet formation in single vs. binary/multiple systems?
    • What range of terrestrial planet compositions is produced through the processes of planet formation?
  • Evolution of planetary systems
    • Are there common criteria for the long-term stability of planetary systems?
    • What is the "typical" planetary architecture, and what range is realized in nature?
    • How does planet migration affect the resulting planetary architectures?
    • What is the correlation of the presence of telluric planets with existence of superearths and gas giants?
    • Is there a correlation between the existence and location of planetesimal belts and the existence of planets?
    • Do exo-Oort’s clouds exist and what is their role in the planet formation/evolution process?
    • What are the properties of potentially existing free-floating Earth-mass objects?
    • Which are the major unique characteristica of the Solar System?
  • Habitable Zone
    • Which parameters determine the region of the habitable zone in planetary systems? (Rem.: Is the term ``habitable zone’’ a good working term at all?: a) There are many parameters that play a role to provide liquid water. b) There are many further parameters — beyond the existence of liquid water — that obviously played a major role to make Earth habitable.)
    • Are giant outer planets a prerequisite for inner telluric planets with habitable zones?
    • How does the stellar habitable zone evolve in time?
    • Which are additional criteria which determine the habitability of planetary satellites?
    • Is it possible to identify / separate a galactic habitable zone (bulge, disk, halo, clusters)?
    • How might the formation history and subsequent dynamical evolution affect the potential for habitability? (e.g. outgasing, loss of atmosphere, internal energy and hence plate tectonics, impacts, orbital change, stability).

Saturday 5 September 2009 by Vincent Coudé du Foresto