Delivery of water to the early Earth
There is very good reason to think that the Earth's water came to our planet very early, although the grains that accreted to form planetesimals near the Earth's orbit are unlikely to have contained enough water. Since a cometary late veneer seems excluded, carbonaceous chondrite material from the outer parts of the asteroid belt is considered a likely source for the Earth's water. Recent planet formation models support this view. However, the origin of the water in carbonaceous chondrites has not been clarified, and the location of the snow line in the solar nebula is open to debate. I will present arguments concerning all these issues and describe new dynamical simulations done at Uppsala Observatory in order to explore the role of icy planetesimal scattering from the giant planet accretion zone in
bringing ice into the C-type asteroids.