Exploring the Origin of Volatiles in Terrestrial Worlds

Abstract:

Given the central role of carbon and nitrogen in the chemistry of life,
it is a fundamental question as to how these volatile elements are
supplied to the Earth, in what form and when. In this talk I will
outline our knowledge about carbon and nitrogen in the Earth and discuss
the potential reservoirs available to supply needed C and N to a
young-forming planet. Based on elemental ratios in these key
reservoirs it is clear that both C and N show a marked deficiency in
solar system rocks with organics as the main carriers in primitive
meteorites. An important conundrum lies in the fact that nearly half of
the carbon in the interstellar medium is found in some refractory solid
state which is inconsistent with the composition of rocks in the inner
solar system. In this talk I will approach origin of terrestrial C and
N from a variety of avenues. First I will outline a potential solution
to the carbon deficiency via oxidation on the heated disk surface.
Second, we will explore the extent to which interstellar chemistry could
be responsible for implanting the initial organic ices seen today in
more complex forms embedded within primitive meteorites. If time allows
we will also discuss whether Solar Nebula water was inherited from the
interstellar medium or significantly altered via the active chemistry
associated with the gas-rich stages of planetary birth.