Speculating Gliese 581 g

[Delphiki]

[1009.5733] The Lick-Carnegie Exoplanet Survey: A 3.1 M_Earth Planet in the Habitable Zone of the Nearby M3V Star Gliese 581

I've been really excited about this planet since it was first recorded in late September. Since this is currently the most likely candidate for life outside our solar system, and it's so relatively close (only 20 light years), this may indicate that the f sub l variable in the Drake equation might be pretty large. That's assuming there is life on GL581g, of course.

One of my favorite things to do is speculate on what this life might be like. Would it even consist of similar biological kingdoms? Is there a particular level of taxonomy that is consistent throughout the universe or is each planet completely unique? Considering that most assume life would be carbon based, and therefore consist of the same organic compounds, at what point does it's evolution begin to differ from the lineage that life on earth followed?

The environment could be potentially accommodating for the dawning of life, but at what point to the differences in environment actually mold it's evolution?

If GL581g had plant life, would it be very dark in color to absorb as much life as possible in order to perform photosynthesis?
What other impact would the higher gravity have on the evolution of the animal life?
What other gases would exist in it's atmosphere and how would the life there process it?
Would all the essential organic compounds even be as probable surrounding a red dwarf star?

 

[Naraoia]

Wait till we know for sure Gliese 581 g even exists

Those are intriguing questions, though I think some of them can't be answered without actually finding extraterrestrial life.

Re: photosynthesisers, that's my initial thought as well (that was a cool SciAm feature, btw), but might tidal locking - which may mean constant exposure to light for some plants - have an effect? (Speaking of tidal locking, does the extreme energy influx gradient between the two sides of the planet create strong winds?)

As for gravity - I'd imagine larger gravity would just make "animals" smaller and any skeletons they may have more robust than we're used to on earth. Might make flight more difficult, too, but I'm not sure there would be an additional effect there beyond the general downsizing. Then again, biomechanics ain't my field...

 

[Upisoft]

(Speaking of tidal locking, does the extreme energy influx gradient between the two sides of the planet create strong winds?)

Yes, it can. In the same way the hurricanes are created by the spatial lock (almost fixed rotational axis) of Earth.

 

[Exial]

I sometimes wonder if we will find a planet full of Pokemon...

 

[Delphiki]

Wait till we know for sure Gliese 581 g even exists

That's true!

Re: photosynthesisers, that's my initial thought as well (that was a cool SciAm feature, btw), but might tidal locking - which may mean constant exposure to light for some plants - have an effect? (Speaking of tidal locking, does the extreme energy influx gradient between the two sides of the planet create strong winds?)

I did forget that they said it was likely tidal locked. I'm not familiar with how they determine this, though.

As for gravity - I'd imagine larger gravity would just make "animals" smaller and any skeletons they may have more robust than we're used to on earth. Might make flight more difficult, too, but I'm not sure there would be an additional effect there beyond the general downsizing. Then again, biomechanics ain't my field...

Hey, I officially don't have ANY field! It's still nice to speculate based on what you DO know even if it doesn't get you anywhere. A bit like day dreaming.

 

[sandwiches]

Wait till we know for sure Gliese 581 g even exists

Those are intriguing questions, though I think some of them can't be answered without actually finding extraterrestrial life.

Re: photosynthesisers, that's my initial thought as well (that was a cool SciAm feature, btw), but might tidal locking - which may mean constant exposure to light for some plants - have an effect? (Speaking of tidal locking, does the extreme energy influx gradient between the two sides of the planet create strong winds?)

As for gravity - I'd imagine larger gravity would just make "animals" smaller and any skeletons they may have more robust than we're used to on earth. Might make flight more difficult, too, but I'm not sure there would be an additional effect there beyond the general downsizing. Then again, biomechanics ain't my field...

In stronger gravity, could water-dwelling organisms fare better and possibly be larger than land-dwelling organisms?

 

[Delphiki]

In stronger gravity, could water-dwelling organisms fare better and possibly be larger than land-dwelling organisms?

They already are in our current gravity. For example, what's the most massive animal ever known to exist?

Blue whale - Wikipedia, the free encyclopedia

Perhaps the differences would be far more contrasted? I'm not sure. Though both the water and air pressure would be significantly greater on a planet like GL581g due to the higher mass, wouldn't it?

 

[sfs]

Wait till we know for sure Gliese 581 g even exists

Quite. In September it existed, and then in October it had never been there -- according to a competing study. More data needed.

 

[Naraoia]

I did forget that they said it was likely tidal locked. I'm not familiar with how they determine this, though.

I just looked up tidal locking on Wikipedia, because I only remembered something vague about orbital radiuses. Seems like a heck of a lot of parameters are involved, some of which can only be guesstimated. Also, I get the impression that either tidal locking or orbital resonance is pretty much an inevitable outcome for anything orbiting a larger body - it just takes a lot longer if the object is small and/or far from whatever it orbits. So I guess in the case of G581g, it's the closeness of the orbit that makes folks think it's locked.

That was quite interesting, actually.

Hey, I officially don't have ANY field! It's still nice to speculate based on what you DO know even if it doesn't get you anywhere. A bit like day dreaming.

Speculating about extraterrestrial life makes me all wistful.