November 26, 2013
The first images that really excited me were of the Hellas impact basin, with the great outflow channels (Dao and Harmarkis) together with, to the east, the Reull Vallis. Important because Hellas is such a large crater that if any impact would remove atmosphere, Hellas would. The huge fluid flows together with what looked like massive alluvial deposits had to post-date impact, as the alluvial deposit had to be into the already formed crater. The question then was, how could water flow when the temperatures had to be significantly below zero? As a chemist, there was only one answer: the water had to contain ammonia. Where did that come from? Well, answering that led to my alternative theory of planetary formation, which, I must confess is generally ignored. The alternative is based on the requirement that initial accretion depends on chemistry, not gravity, because only chemical interactions are strong enough to hold the intermediate objects together. So, why is this image so important? Because the walls of the valley show a form of erosion expected from leaching, and the pools at the bottom are exactly what this concept expects. Perhaps this is an imaging fluke/error, but if nothing else, the provision of what is predicted always cheers up a theoretician!
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