Forming Earths and Mercuries: solids less volatile than water
by
Alexander Hubbard(Nordita)
→
Europe/Stockholm
122:026
122:026
Description
Life requires a variety of chemicals and elements. The question of water,
how it was delivered to Earth and how it would be delivered to exoplanets,
has taken a central position. However, other chemicals and elements are
also important. Earth is significantly (~80%) depleted in elements
important for life like sodium and potassium, both much less volatile than
water, but much more volatile than silicon, magnesium, or iron. Part of
the composition of planets is set during their formation process, when the
solids are still in sub-cm dust grains. I will discuss both the supply of
moderately volatile elements to the proto-Earth, and why Mercury is
extremely iron rich. Both processes should play major roles in exoplanet
formation, with consequences for their chemistry and hence any possible
biology.