As water comes off the rings, it is split by sunlight; the resulting hydrogen and atomic oxygen are then lost, leaving molecular oxygen.

The knock-on effects to the International Space Station are quite dramatic … (long delays) could potentially be a show-stopper for the whole thing.

In general, one has to ask why complete the International Space Station anyway. One worries about putting lots of resources into that because it diverts resources from the scientific exploration which needs to be done.

Otherwise the investment which has gone in has been a waste up until now.

Venus was born with the same sorts of constituents as Earth, which means there was some water in the environment. Some more probably came in from comets.

Venus provides an extreme test for the atmospheric physics models that we have for Earth.