Planetary life and lunar life

[MechAg94]

nobody brought up the impact of extreme tides, from being a satelite to the larger planet?  i would think the devolopment of life would be greatly different, assuming both planets had similar structures otherwise.

also, i feel that it is highly unlkely for the devolpment of 2 liveable planetary systems within the "grow zone" of one star.  depending on the amount of time it took life to evolve, the planets would likely merge into one before intelligence was observed.

. If you have a gas giant in the grow zone, it makes it easier. 

[Regolith]

Habitable systems, for one.  I bet they are not as common as the elements in the periodic table.  If'n we go out and holler, "Hey, we are over HERE!" we have told another SFS the location of a habitable planet.

Well, that also depends. We don't know if Earth is a good representation of what is required for intelligent life, since we only have a sample size of one. It may be the norm, or we may be freaks of nature when compared to other life forms. We do know that life can live outside the normal conditions that can support humans, so it's quite possible that an alien species may not find Earth inhabitable any more than we'd find Venus a great place to live.

[roo_ster]

Well, that also depends. We don't know if Earth is a good representation of what is required for intelligent life, since we only have a sample size of one. It may be the norm, or we may be freaks of nature when compared to other life forms. We do know that life can live outside the normal conditions that can support humans, so it's quite possible that an alien species may not find Earth inhabitable any more than we'd find Venus a great place to live.

True, sample size of one. 

OTOH, I do think that any biologically-based SFS will require something similar.  For example, outside of incorporeal beings, a volcanically active moon with almost zero atmo is a poor candidate to develop a SFS. 

[seeker_two]

Yeah, cause if you send only a small group, all it would take is a 70 year old battleship and some ocean buoys to ruin your trip. 

Especially if it's a Japanese battleship.....that can fly!....

[Perd Hapley]

Resource competition? What possible resource is there to fight another species over when there are thousands of uninhabited systems full of every element in Mendeleev's table?

Some moons may consist of a more flavorful cheese than other moons.

[MechAg94]

As far as the number of habitable planets, that research looking at other stars is finding evidence that stars with planets and even planets in or near the life zone are more common than we thought.  Until we travel to other systems, we really can't know what is out there. 

As far as hiding from alien species, I saw one show talking about research trying to differentiate light spectrum when looking at other stars.  They pointed out that anyone looking at earth who could do that would see that we have clouds and water and atmospheric oxygen, regardless of whether or not they detected us. 

[MechAg94]

http://www.foxnews.com/science/2012/12/28/first-alien-earth-will-be-found-in-2013/

First 'alien earth' will be found in 2013, experts say


Read more: http://www.foxnews.com/science/2012/12/28/first-alien-earth-will-be-found-in-2013/#ixzz2GMK2yFGf