A couple weeks ago the stupid gawker sci-fi blog io9 that I read despite how dumb it is posted an interview with Steve Vogt, the astronomer whose team discovered that awesomely earth-like planet 20 light years away. He insists that this planet must have life on it, which is fairly unscientific of him but I tend to agree, because I love the idea of life on other planets, no matter what, and because it just seems so probable to me; after all, we have pretty decent suggestions of life, past or present, occurring on a pretty large number of bodies just in our solar system alone, so this rocky planet right in the "habitable" zone of its star seems like a good candidate, you know?
Anyway, Vogt was talking about his reasons for being so sure that there's life on this planet, and he described things in a way that had never really presented itself to me before, and I liked it, so here it is:
[T]he universe is a vast place and most of it is totally unavailable for life as we know it. There are two things in the universe you can't get around: Temperature and gravity. So if you are in interstellar space you're at 2.7 degrees kelvin. Your atoms are hardly vibrating and you're not going to be alive. Life as we know it can't survive. So you have to be near a star. That's good, but stars have gravity and you can fall into them. Your only hope is to be near a star but not falling into it – you need an orbit. And that's magical. That's where you can have enough warmth, but not turn into a cloud of plasma because you've fallen into the star. So when you have a planet in orbit and it's the right size and in the right orbit [like Zarmina], it's a very special place. There are many planets like that but we didn't know that [until our discovery].