Gary sent in the link to https://phys.org/news/2023-11-unveiling-mercury-geological-mysteries-salt.html … It was the salt that captured his attention. Glaciers of salt. How did it get there. This is the puzzle confronting geologists, it would seem. We are told scientists have uncovered evidence of potential salt glaciers on Mercury, revealing a volatile environment. The volatility bit is not a surprise as Mercuty is the closest planet to the Sun. Is there really salt on Mercury – and how did they discover it. Modeling played a role it seems. One wonders about the glaciation bit – that close to the Sun. There is however a logical reason why this was suggested. The salt is reported as having an origin in rich layers exposed by asteroid, or meteor, bombardments. Other research has claimed there are nitrogen glaciers on Pluto – in a sort of planet a long way away from the Sun. It should be extremely cold on Pluto – hence the idea of glaciers. Salt glaciers on Mercury are an intriguing idea. However, it is the models they used that indicated salt flow likely produced the glaciers – if that is what they are. Specific salt habitat on earth can be found in the Atacama Desert in Chile, as a result of evaporation of salt water lakes that once existed close to the sea. Lagoons that were lifted on high. Not sure that is the same as the salt deposits on Mercury but this is the example they use in an attempt to explain its existence. Did Mercury once have water. This seems to be what they are saying. It probably did have water if Mercury is a captured comet or asteroid. However, they are talking about water billions of years ago – in the primordial Mercury [as part and parcel of the formation of the solar system]. We have buried deposits of salt on the earth. A huge seam of salt underlies the North Sea for example. Perhaps they are thinking in terms of something similar on Mercury, exposed by impacts of objects rounding the Sun. Then we have the Borealis Chaos – located at Mercury’s north polar region. They project it as a region of disintegration. Perhaps it is – but it may also be a region directlly affected by bursts of solar wind. The creation of auroral phenomena has a geomagnetic connection. One might suspect the region is actually associated with stripping away of the geology – as they appear to suggest. Exposing another more ancient layer of pummelled craters. This has been identifed via gravity studies which indicate the upper layer was emplaced, sitting on top of an already solidified landscape. It may of course represent a congealed landscape that was subsequently buried and then over time geology produced the now mainly stripped away present geological layer. The authors seem to think this goes against the grain of mainstream geological thinking. Especially on the origin of volatile rich layer formation. The argument centres around Mantle differentiation processes and how minerals separate into different layers within the planet’s interior. Instead, the evidence, they think, points to a grand scale structure within the Mantle, possibly stemming from a primordial hot atmosphere early in the history of Mercury. The atmosphere collapse may have occurred even during the night time when the planet was not exposed to the heat of the Sun. In fact, if Mercury once had a watery surface back in the day, in the ancient landscape, it may account for the salt deposits. Dried up lakes and rivers, and ponds of salt water. Water may have been swished up into space by the chaos of the geomagnetic processes inaugurated by the solar wind. A remarkable train of thinking. Not sure if it makes sense. The proof will be in the fetching of a salt sample.
In the news recently was the discovery of an exoplanet – raining sand. Its atmosphere contains a lot of silicate. Gary sent in a video –