Exoplanets theoretically possible!

The movie Avatar with it's blue faerie creatures living on a moon has inspired some Real Lab coat wearer's into thinking outside the box, which is always cool :)

They have been kicking around the idea of something called an "Exoplanet" which is basically a moon with the possibility of some critters being on it. Now what makes this really cool is that we generally think of life only being capable of existing on planets in the "Goldilocks Zone" Get it? Not too hot, not too cold; which allows us to have liquid water. Water is about 70% of your body meaning it's pretty damn important for you and me, and apparently life everywhere.

There are some exceptions though, supposedly there was some thought about there being life under the ice of one of our outer planets. I think it was Pluto but the poor thing isn't a planet anymore so it may be another, but life like you and me wouldn't exist there anyway, the best we can hope for are micro-bacteria anyway. Which are capable of existing in much harsher conditions then most life, such as the inside of a Geyser.There is also the Tardigrade which can survive in the confines of space without dying, which is truly amazing but if they can do it, there isn't any real reason there can't be foreign life forms capable of the same thing. 

These Exoplanets unlike planets we think of in the traditional sense are somehow using gravity to make them warm enough to have liquid water and be habitable. Personally i only got through the first physics class so far, the one with Evil Knievel problems, so it's a bit over my head. The main point here is, because of the heat being generated from their close proximity to Gas giants they are capable of existing outside of the Goldilocks Zone. Giving us a much larger amount of planets capable of sustaining life. Fascinating, brilliant, Genius, Somebody deserves an award.

But i do have one question about all of this, plants as we know them use the Sun for photosynthesis allowing them to create energy and ultimately survive. These plants in turn create Oxygen so you can i can survive, without plants we'd have trouble surviving, of course there's submarines so maybe our tech has hit some interesting plateu's but the idea of seeing any life form on our level without plants seems impossible.

I can't help but wonder if Plants will receive enough light from too far past the Goldilocks zone  to be able to survive and create Oxygen for our would be amigo's. Now given most people don't like hearing the "alien" talk anymore but there's really only two exciting possibilities about finding planets that can sustain life. Those are either Moving there or seeing what's already hanging out.