Titan vs Earth: Hydrocarbons vs Water - Pros and Cons for Thriving Life Forms

[Terdbergler]

Water is incredible. We see lakes of hydrocarbons on Titan and they remind us of water lakes on Earth, so we postulate that an entirely difference sort of life might thrive there. But do liquid hydrocarbons really have what it takes to do all the things that water does?

Here's my question: hydrocarbons vs water? Pros and Cons. How do they match up? Can hydrocarbons cut it?

 

[Drakkith]

No, hydrocarbons do not have the same chemical properties as water and cannot serve the same purposes.

 

[Mordred]

lets expand on Drakkith's post a bit. Carbon as an element has a high valence, in other words its potential to bind to other elements is high compared to oxygen or hydrogen. As such it readily combines to form bio-chemical molecules. This makes carbon suitable to the production of protein,DNA and RNA chains.

Water however provides a medium which allows mixtures to combine, another liquid medium can do the same, however water has Hydrogen and oxygen content, so has numerous bio-chemical combinations with carbon.

to completely understand how important carbon is study bio chemistry, been years since I took a course on it lol (close to 2 decades ago)

edit: a very quick google reference is this and by no means a complete picture, however shows some of the basics
http://www.biologymad.com/resources/Ch 3 - Biochemistry.pdf

PS note the molecules of life section

 

[Terdbergler]

So the fact that there is a lot of carbon inside lakes of methane, ethane and propane is a good thing, but the fact that the vast majority of that carbon is all tied up with hydrogen is a bad thing?

 

[Terdbergler]

Also, I understand that one of water's virtues is its polarity; it's a great solvent. Are liquid hydrocarbons good solvents?
Given that the carbon is already there in the hydrocarbons, and it's already linked up with the hydrogen, would the hydrocarbon molecules bond with the water from the water rocks on Titan? Would there be the same potential for long protein chains?

 

[Terdbergler]

Also, given the surface conditions on Venice, which element or compound COULD hypothetically pool up in liquid form on its surface in the form of lakes?

 

[Terdbergler]

Venus. Not Venice. I'm an idiot :)

 

[Drakkith]

So the fact that there is a lot of carbon inside lakes of methane, ethane and propane is a good thing, but the fact that the vast majority of that carbon is all tied up with hydrogen is a bad thing?

In what context are you using good and bad?

 

[Mordred]

Ethane and methane, are not good contributors to life, hydrocarbons are. However this doesn't mean life will form in and of itself. There is very little Oxygen on Titan. Oxygen is needed for DNA strands. However it may or may not be possible to have non water based information carrying strands.

http://www.ess.sunysb.edu/astro/seminars/archive/JS09/jcl27Feb09-2.pdf

here is one paper covering the possibility of non Oxygen/carbon based life forms
http://arxiv.org/ftp/physics/papers/0501/0501068.pdf

There is a possibility of a silicon based lifeform as well, we simply do not know well enough. Our knowledge of lifeforms is primarily water based. Such as the examples we find on Earth. So much of the possibility of other forms of life is mostly conjectural though research is being done in those directions

if you look at the first link I posted in post#3 and look at all the chemical compositions, you can quickly see how important oxygen is.