shouldn't be over looked, we are just one species of animal amongst many forms of life on the blue speck from the smallest bacteria to the tallest tree and anything in between and beond .is a pitty the whole picture can be ignored for the sake of a so called "intelligent life" form 
...oh and while I'm ranting... 
May as well say that you're right - conditions on any of the moons thought to have liquid water would be pretty inhospitable to human life. But conditions would be far better than they are in the vacuum of space itself and there are humans living and working in space every day.
(.).)
Hans is very charismatic but also quit utopian. I like TED talks but sometimes they can be pretty romantic.
What Hans says is right, the it's pretty tough for us the above 'air line' to tell those below the poverty line that "ohh sorry, where using too much energy, so you're not allowed a washing machine" .. But life is tough.
Hans thinks with green energy the world can support 10+ billion living a lavish 'green' lifestyle with zero poverty.. But at the moment the 'Green Lifestyle' is imaginary.. It may not work, and if it did it wont be here in the foreseeable future.. It takes time to introduce new technologies.
The biomass of humans is not much relatively compared to what?. I did like your calculations, a 1km cubic orgy of the entire population is a frightening thought.. But you should also include the biomass of all our supporting livestock, here is another TED talk by MacCready, Who would disagree with the Utopian Hans.. 2 billion people is all the planet can take, with green technology..(edit* it's just a 3min edit from a talk, one that seemed less utopian than Hans)
woohoo, i thought i was born a dummy, now i got someone to blame for my dumness
thank you ajenda 21
I do not totally agree with Barn but you have to at least give him some for the way he feels and sticks to his opinion and give hime another one for the research work!
+2 Barn
If we found life in our solar system it would mean that life is ridiculously common.. Life independently developing twice in the same solar system, would mean the universe would be even more crowded than earth.
I read somewhere that it was very likely that Europa (one of Jupiter's moon) had some sort of life on it as they detected water kept warm by volcanic activity under the ice crust.
en.wikipedia.org/wiki/Europa(moon)#Subsurface_ocean
I now feel like a real douche. I thought Barnsey made a nice drawing of a lovely little doggie, how sweet I thought, then Barnso said it was a picture of his penis ,and then I had to go to the bathroom to see if it was anything I should be concerned about . And it turns out that Mr.barny needs to see a doctor
Its was actually a drawing of an Alien life form. I saw it when I once took a hit from some Glag Glue and Baby Jesus came and spoke to me and told me all about life in space..
He said all the other planets are generally populated with Phallic life forms. And when these Phallic aliens die, their souls get sent to heaven, where they feed all the Godly...
But I can't take credit for the drawing, It's from the internet, so I imagine I am not the only one who Baby Jesus has spoke to about aliens.. If I'm not alone then it is no delusion..
Here is where I first saw it, in another thread.. From Doggie, credit him with this highbrow content..
I seem to remeber recently that they had discovered an alien microbe in a metor which suggest that all life started with an alien life form microbes from space in metors & this has then mutated to be the current life on earth . This theory would have many life forms in space most possibly on the microbe level & thus unable to be deceted by us at this stage.
