I’ve never been fond of “habitable zone” defined as 273 to 373 Kelvin on the surface.
Because deeper can be hotter, and water is more stable at depth.

A new idea from an old SciFi book is to look for halogenated organic compounds as a sign of life in cold environments.
F2O closely resembles H2O in shape and polarity, and is liquid at a temperature of 49.3 to 128.4 Kelvin.
That’s exceedingly cold. Nitrogen melts at 63 Kelvin.

F2O is much more reactive than H2O, but it would need to be in order to operate at such low temperatures.

Can you see any reason why, in a cold environment with little free hydrogen, we wouldn’t see a carbon-based life form using fluorine instead of hydrogen? And thus have a habitable zone from 50 to 125 Kelvin. Just right for Titan, but a bit hot for Pluto.

Elements HCONSP replaced by FCONSP.

tunnelling

mollwollfumble said:

I’ve never been fond of “habitable zone” defined as 273 to 373 Kelvin on the surface.
Because deeper can be hotter, and water is more stable at depth.

A new idea from an old SciFi book is to look for halogenated organic compounds as a sign of life in cold environments.
F2O closely resembles H2O in shape and polarity, and is liquid at a temperature of 49.3 to 128.4 Kelvin.
That’s exceedingly cold. Nitrogen melts at 63 Kelvin.

F2O is much more reactive than H2O, but it would need to be in order to operate at such low temperatures.

Can you see any reason why, in a cold environment with little free hydrogen, we wouldn’t see a carbon-based life form using fluorine instead of hydrogen? And thus have a habitable zone from 50 to 125 Kelvin. Just right for Titan, but a bit hot for Pluto.

Elements HCONSP replaced by FCONSP.

It would at least be interesting to observe, from outside the closed environment.

Question:

In this environment are you still hoping to use dioxygen as your main ambient oxidant?

Because here we rely on the oxidation of carbohydrates
eg 2C6H14O2 + 17 O2 -> 12CO2 + 14H2O

Now, simple hypofluorites do exist with structures analogous to carbohydrates. Do they have enthalpy high enough to support reactions such as:

2C6F14O2 + 17O2 -> 12CO2 + 14 F2O

?

Btw I’m with you all the way on that habitable zone bullshit. The environments in which we’ve found life can survive have been very broad.

And life based on silicon?

Higher temperatures, longer time frames. Silicon produces complex molecules. Ion transport happens in phyllosilicates.

mollwollfumble said:

F2O is much more reactive than H2O, but it would need to be in order to operate at such low temperatures.

G2O would seem to be a good compromise.

Woodie said:

mollwollfumble said:

F2O is much more reactive than H2O, but it would need to be in order to operate at such low temperatures.

G2O would seem to be a good compromise.

It’s Economic Science ¡

https://www.g20.org/

It’s Economic Science ¡

https://www.g20.org/

dv said:

Question:

In this environment are you still hoping to use dioxygen as your main ambient oxidant?

Because here we rely on the oxidation of carbohydrates
eg 2C6H14O2 + 17 O2 -> 12CO2 + 14H2O

Now, simple hypofluorites do exist with structures analogous to carbohydrates. Do they have enthalpy high enough to support reactions such as:

2C6F14O2 + 17O2 -> 12CO2 + 14 F2O

?

(Dang it, lost my reply, trying again).

I’m not sure that O2 would be an appropriate oxidant. https://en.wikipedia.org/wiki/Anaerobic_respiration lists twelve electron receptors other than O2 that are being used here on Earth.

Let’s try Gibbs free energy (if I can) for these reactions. At room temperature only, could be quite different cryogenic.

2C6H14O2 + 17 O2 -> 12CO2 + 14H2O
Glucose oxidation -2870 kJ/mol glucose.
Glucose fermentation -218 kJ/mol glucose

F2O -545.50 kJ/mol
H2O −237.13 kJ/mol
CO2 −394.38 kJ/mol
No easy info on C6F14O2

The citric acid (Krebbs) cycle starts with pyruvate: C3H4O3
C3H4O3 -420.2 kJ/mol
C3F4O3 = Carbonofluoridoyl 2,2,2-trifluoroacetate = no free energy or enthalpy info on the web. Can’t answer question.