Exploring Life on Titan & Beyond: Questions for Astrophysicists

[curious_cat]

Hello, I'm new here, and I really don't know much about astrophysics so would appreciate it if your replies were as simple as possible
I've read that scientists are hopeful to find life on Titan, Saturn's largest moon, because the planet resembles Earth in its earlier stages.
I have a few questions about that:
1) Theoretically, how long would it take Titan to develop to Earth's level?
2) If it does develop this much, what would it be like?
3) What are some of your theories on this topic in general?

On a not so related note:
4) Some of the planets are not able to support life because they are either too far away or too close to the sun. Given that the sun was the right distance from a planet, is there another one which would be able to support life form?
5) Is it possible that in the future technology advanced enough would be created for Earth's inhabitants to be able to adapt to other planets?

Please be as elaborate as possible Thanks for everything in advance!

 

[qraal]

Hi

While we like abstract theorising here at Physics Forums, astrobiology isn't really astrophysics, but I'll try to answer with as much astrophysics as I can.

Hello, I'm new here, and I really don't know much about astrophysics so would appreciate it if your replies were as simple as possible
I've read that scientists are hopeful to find life on Titan, Saturn's largest moon, because the planet resembles Earth in its earlier stages.

Kind of resembles. Both had/have nitrogen and methane, but Titan is too cold for that essential of life, oxygen, which is currently locked up as carbon dioxide and water ice. Any life would be based on hydrocarbons like methane, but as we don't have any examples of purely hydrocarbon life here on Earth we don't know if it's possible. There could be life inside Titan, in the possible sub-surface ammonia/water oceans, but it would need an energy source and we're unsure what's available under all that crustal ice.

I have a few questions about that:
1) Theoretically, how long would it take Titan to develop to Earth's level?

There is no definite theory that can tell us, but if Life's pace is related to the available energy, then it might take a very, very long time because Titan's energy supply is less than 1% of Earth's.

2) If it does develop this much, what would it be like?

You tell me. Currently all options are open.

3) What are some of your theories on this topic in general?

Not really an astrophysics issue. Try another section of the forum.

On a not so related note:
4) Some of the planets are not able to support life because they are either too far away or too close to the sun. Given that the sun was the right distance from a planet, is there another one which would be able to support life form?

Not sure what you're asking. Can you restate the question?

5) Is it possible that in the future technology advanced enough would be created for Earth's inhabitants to be able to adapt to other planets?

Please be as elaborate as possible Thanks for everything in advance!

WHat sort of technology? Biotech? We can 'adapt' in space-suits to a lot of environments, but I suspect you mean something else. As biotech only works with biology we have living, working examples of it's hard to see how we can adapt to environments we don't see any living thing in. But so long as there's an energy and matter flow, there might be a way of making living things there.

 

[gazebo_dude]

Welcome!

Disclaimer: I am not an astrophysicist, or an astrobiologist, so my views are those of an (interested) amateur. I would gladly be corrected by an expert.

1) Well, on Earth life took ~4 billion years to reach its present state. A sample size of one is not good for extrapolation, especially to an environment as different from ours as Titan. For life on the surface I would guess that there is a trade off between Titan being much colder than Earth (not much in the way of usable energy flows = slower evolution) and a harsher radiation environment on Titan (is this right?) = faster evolution. In fact, the surface of Titan is so cold that I bet life as we know it is impossible there, except maybe some micro-organisms.

The place where there is a real chance for life on Titan is deep below the surface where tidal friction due to Saturn's gravity produces enough heat to melt the ice. Liquid water + temperature gradient + rich enough chemical soup might = life.

2) Who knows! Feel free to speculate and maybe even write some good sci-fi about it. People say that evolution is random. Of course it isn't really random, but what they mean is that evolution is so contingent on all the tiny little details of the environment and the accidents of life that it is effectively impossible to predict with any certainty the way it would go. All you can say is that there will be certain general trends, for instance, towards increasing complexity over time.

One of my personal favorite alien ideas is an intelligent cephalopod (cuttlefish/octopus/squid etc)-like species with complex societies etc. Seems about equally probable to me as intelligent monkey-like creatures.

3) As far as I know the main contenders for life elsewhere in the solar system are: Titan, Enceladus, and Europa. There may be others. In all of those the life would likely be aquatic life living in a water ocean deep below the ice surface, possibly forming ecosystems based on energy and chemical flows from deep ocean vents similar to those on Earth. My personal opinion on all this is: if the conditions are right... maybe. Will we ever be able to make contact with such life? I very much doubt it unless we are talking about the far future.

4) In all of these discussion one should use the preface "life as we know it." That said, Venus and Mars are also in the Sun's habitable zone, where the temperature is such that liquid water could exist on the surface. However, Mars was too small for its gravity to keep a thick atmosphere and hence the surface temperature dropped below the freezing point. Venus had the opposite problem when volcanic activity spewed an enormous amount of green house gasses into the atmosphere and now the surface is so hot it could melt lead. Of course the true story for both planets is far more complicated than that but I'll leave that for the experts.

5) I don't see why not, unless we kill ourselves off or get wiped out by an asteroid first.