Connecting clustered star formation with the origin of life.

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How do stars and their planetary systems form? How did life originate on Earth, and are we alone? These questions are deeply linked.  The arc that connects them begins with the fact that most stars form as members of clusters containing dozens to millions of stars.  Clusters arise in clumps of up to a few light years across within large (300 lyrs)  filamentary, magnetized giant molecular clouds (GMCs).   Over-dense regions in clumps collapse to produce stars within protostellar gas/dust disks, which can now be imaged at submillimeter wavelengths by the Atacama Large Millimeter Array (ALMA).  The properties and chemical composition of these evolving disks in turn determine the kinds of planets and atmospheres that form -  connecting planet formation with the observed chemical and dynamical properties of exoplanetary populations.   The  origin of life on rocky worlds requires not just water, but a source of biomolecular building blocs in environments in which genetic polymers can form.  These building blocks can be delivered by meteorites or made by exotic chemistry in certain kinds of planetary atmospheres. The long-term objective of my research program is to link the origin of genetic polymers on newly formed habitable planets to the origin of the chemical, physical and dynamical properties of the planetary systems of their host stars in forming star clusters.   We will perform global simulations of magnetized galaxies using state of the art radiative magnetohydrodynamic (RMHD) codes to study how GMCs and their massive star clusters are built.  By using zoom in techniques, our  RMHD simulations will, for the first time, explore the properties of cluster formation in magnetized GMCs down to protoplanetary disk scales.  We will determine the upper mass limit of their stars as well as  the distributions of physical properties of their magnetized disks  A combination of novel astrochemistry and N-body dynamics methods will be used to compute the gravitational interactions between planets and the disks, and track their chemical properties as they accrete material from their disks.    Planets also migrate by exchanging angular momentum with gaseous disks.  New advances emphasize that magnetized disk winds - not disk turbulence - provide these torques.  I will develop a novel theory of planetary migration based on this concept.   With the composition of planets and atmospheres in hand, we will then compute the chemical conditions under which the building blocks of RNA molecules can form in planetary atmospheres.  This provides input for our experiments on how the first genetic polymers (RNA) formed in prebiotic planetary conditions  (warm little ponds) - to be carried out in our newly completed, CFI funded, Origins of Life Laboratory (OoL). This unique world  facility features a planetary simulator that creates a wide range of planetary environments in which we can study the rate at which polymerization and resulting molecular evolution can occur.