Space/Science — HabitableZone

Space/Science » in reply to re: The word: Thermophysical.

Thermophysical vs hydrothermal
Nick Hoffman — (archived)

Not quite, Marcia.

In the Context that Christensen uses it, it essentially means "IR emissivity and absorption" which is a function of temperature.

There probably isn't a word in our Earth-derived geologic vocabulary to describe the process, especially since we can't agree on precisely what conditions this took place under.

To follow-up on jms's point:-

On Earth, hydrothermal processes imply waters at elevated temperatures, perhaps close to the surface boiling point or beyond it. When hydrothermal waters reach the surface they equilibrate thermally and chemically, producing geysers, mineral deposits, and alteration products.

On Mars, the mere presence of liquid water puts us in that regime, comparatively, given a surface temperature of -60 C and low pressure. Anything aqueous that can flow at Mars ambient conditions is either so warm that it would boil spectacularly at the surface (geysers) or has so strong a chemistry that it would corrode rock on contact (The sulphate alteratation of basaltic rocks that we have seen principally at Meridiani, but hints of at Gusev).

I stick with hydrothermal, for now, until we coin a better and more specific phrase for Mars!

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