Sun, Oxygen, Wind and Water - What other Chemistry could be so good? (Fundamentals of Life)

[JoeSchmuckatelli]

Spoiler

Not sure if this is going to work as it's own topic - but @KSK wrote about chemistry lately, and @kerbiloid pointed me to 'Weathering Rind' which is a phenomena I've seen a lot of, but did not know it had a unique name.

Weathering rind - Wikipedia

 

If you think about the pre-colonization of Earth's landmasses in the Precambrian time, Earth's chemistry was doing a lot to 'prep' the land to accept life.  Specifically solar energy, wind, and rain and oxygen were already starting to break up bare rock into much smaller particles.  'Soil' as we understand it, would not exist until life infested the rocks - but having sand and dust in great quantities, created by the action of Solar radiation, heating and cooling, wind and water (liquid and glacial) erosion and the chemistry of Oxygen reacting to almost everything - the nooks and crannies that life could find a foothold in were legion.

While this topic quite often focuses on 'goldilocks zones' where water can be liquid - there are other planetary-like bodies with liquids on their surface.  Titan for instance.  Methane, not water.

Given what we know... would chemistry in another place, like Venus or Titan that has Solar, liquid and wind energy present, could the chemistry similarly break up rocks to create the basic stuff for soils; or is 02/H20 reactions required for terrestrial rock chemistry to break down and create the conditions for local bacteria and other simple life to create a soil analog?

(Assumes extraterrestrial rocks have similar chemistry to Earth rocks, based on the fact that Meteors have a recognizable chemistry not totally alien)

meteorite | National Geographic Society

Edited November 27, 2022 by JoeSchmuckatelli

[KSK]

Good question and I’m not enough of a geologist / geochemist to give a definitive answer. With that said:

Minerals tend to be ionic, so they dissolve more easily in polar solvents. Water is an excellent polar solvent and it has unusually high melting points and boiling points for its molecular mass because of hydrogen bonding. That’s helpful because it’s liquid at a relatively high temperature and things tend to be more soluble at higher temperatures.

Ammonia might work too but it’s not as polar and NH…N hydrogen bonds are weaker than OH…O hydrogen bonds, so ammonia has lower melting and boiling points than water. Both of which factors (I think) would make it a poorer chemical weathering agent.

Hydrogen fluoride would be an excellent weathering agent in principle (given that the damn stuff etches glass) but is hellaciously reactive. I’d expect it to get locked away as fluoride minerals in short order, making it an ineffective weathering agent in practice.

Non-polar solvents such as hydrocarbons aren’t much good at chemical weathering as they don’t tend to dissolve minerals. This is helpful when trying to extract them from the ground.

Supercritical fluids  (eg supercritical carbon dioxide) tend to be good solvents and might make decent chemical weathering agents. They’d be very location specific though as they need to be above a certain temperature and pressure.  It’s also  debatable whether life (at least as we know it, Jim) would be viable with supercritical fluids around - I imagine they’d do a pretty good job of dissolving any proto-cells as well as weathering rock.

TL:DR  I’m not sure that water is essential for weathering but it is a very effective and relatively benign weathering agent.

 

 

 

 

[JoeSchmuckatelli]

I'm reading about the chemical reactions of common rock with H2O and 02.  Wondering if there is something unique in that reaction that makes life more common than 'simply having a wet planet'.

Water-rock reaction may provide enough hydrogen ‘food’ to sustain life in cool parts of the ocean’s crust or on Mars | CU Boulder Today | University of Colorado Boulder

I'm not versed enough in chemistry to know whether some of the other things like methane or CO2 might similarly react with the various types of metals and minerals to provide a nutrient base for some form of life... but I haven't seen anything suggesting that either.

[JoeSchmuckatelli]

Although CO2 is usually considered too stable to react chemically with rock, it can bind tightly to the surface by physical adsorption. Eventually it dissolves in water, forming carbonic acid, which can react with aqueous metals to form carbonate minerals.

CO2 mineralization in geologically common roc | EurekAlert!

 

Looks like CO2 needs water to react with rock, but it can bind.  This article doesn't go into what happens if the CO2 freezes - but that's not really an issue on Venus.

[JoeSchmuckatelli]

1 hour ago, KSK said:

 I’m not sure that water is essential for weathering but it is a very effective and relatively benign weathering agent

You know... I did phrase my question as a pretense for weathering - as I was trying to figure out how a non-goldilocks planet might get the precursor of soil.  But truth be told, wind and mechanical forces of freezing might do it... 

Having read what you have written and seeing a few other articles - it looks like the ability to free the minerals in a biologically available way is just as important.  Water is quite good at this and is found in soil and the atmosphere on Earth as well as the rivers lakes and oceans. Methane seas don't look like a good place for this.  "Methane is non Polar and interacts weakly with most materials."

https://www.nature.com/articles/ncomms2697

Goldilocks is looking a lot more Just Right than I thought! 

[kerbiloid]

Just to add some info fuel.

https://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry

the ru wiki article looks bigger

https://ru-m-wikipedia-org.translate.goog/wiki/Альтернативная_биохимия?_x_tr_sl=ru&_x_tr_tl=en&_x_tr_hl=ru&_x_tr_pto=wapp

Edited November 28, 2022 by kerbiloid

[JoeSchmuckatelli]

15 hours ago, kerbiloid said:

Just to add some info fuel.

https://en.wikipedia.org/wiki/Hypothetical_types_of_biochemistry

the ru wiki article looks bigger

https://ru-m-wikipedia-org.translate.goog/wiki/Альтернативная_биохимия?_x_tr_sl=ru&_x_tr_tl=en&_x_tr_hl=ru&_x_tr_pto=wapp

I hate anti-chirality - because we can't eat it.  Sure, we find a great planet with oceans and plants and animals... but everything from the bacteria to the topsoil is fundamentally unavailable to us.  No growing plants or farming Cattle on that planet.  All we could do is study it while the food we brought with us lasts.

What an enormous let down that would be!

 

Thanks for the link: it does talk directly about what I was speculating on above:

Quote

In addition to carbon compounds, all currently known terrestrial life also requires water as a solvent. This has led to discussions about whether water is the only liquid capable of filling that role.

 

Edited November 28, 2022 by JoeSchmuckatelli

[kerbiloid]

8 hours ago, JoeSchmuckatelli said:

I hate anti-chirality - because we can't eat it.  Sure, we find a great planet with oceans and plants and animals... but everything from the bacteria to the topsoil is fundamentally unavailable to us.  No growing plants or farming Cattle on that planet.  All we could do is study it while the food we brought with us lasts.

It isn't a fact that an anti-chirality world is actually probable.

Afair, the prevailing chirality side depends on the native star light polarization, and it may appear that in the world of no anti-matter, and thus one prevailing sign of neutrinos, the polarization properties may be not equally probable.

Though, not an astrochemist.

[JoeSchmuckatelli]

19 minutes ago, kerbiloid said:

It isn't a fact that an anti-chirality world is actually probable.

Afair, the prevailing chirality side depends on the native star light polarization, and it may appear that in the world of no anti-matter, and thus one prevailing sign of neutrinos, the polarization properties may be not equally probable.

Though, not an astrochemist.

I've always kind of read anti-chirality arguments as contrarian.  Sure, a possibility (someone far more educated and better with maths points out a potential problem with being too hopeful vis panspermia).

But such a result just strikes me as less than likely.  Kind of like mathematically it really is possible for me to flip a coin 100 times and get 100 heads with a fair coin.  Possible?  Unlikely.

[kerbiloid]

The bright side of anti-chirality:

1. They can't eat us as well.

2. Any form of personal contacts is safe even without countermeasures.