auto-da-fe

The number is 70 sextillion.

This is the number of stars estimated in the known universe (link).

To put it another way, there are about 10 times as many stars in the universe as there are individual grains of sand on the entire planet earth.

Surely out of all those, there are many, many inhabitble planets. Even if you assume only 1 percent of the stars have habitable planets, that is still 700,000,000,000,000,000,000. Hell even if you say only 1/1000th of the planets have habitable planets, that is still so large a number that it is hard to imagine.

Now out of all of those possibilities, who can possibly imagine that there are no other lifeforms, anywhere?

Not sure if it is proper etiquette talking about alien life in these forums, as I haven't ever seen it done. I jst thought with all the minds around here, I would like to hear some opinions on it. As a serious topic.

markfiend

Strange thing is, we've never found any evidence of space-travelling aliens.

This is known as Fermi's question; So, where are they all?

Division By Zero

I've heard people say it takes just as much faith, if not more, to believe in aliens than it does to believe in gods.

Nonsense.

As you said, in such an enormous universe it's absurd to believe that our planet is the only one capable of supporting any kind of life. If life can arise on one planet, then it can arise on other planets - and I'll bet anything that some of those aliens are intelligent and sentient, just like we are.

auto-da-fe

I'm familiar with Fermi's question, but I think it is lacking in an end all be all answer kind of way. The universe is pretty freaking big, it wouldn't be too hard travel for hundreds of thousands of years, and never come within a couple of billiion miles from earth, or even a couple of billion miles from the Milky Way itself. That is my problem with Fermi's, it assumes that if there are space traveling aliens, then we should have seen them by now, which is not true, and assumes too much (almost qualifies for a straw man arguement wouldn't you say)

braces_for_impact

I find it a bit disheartening that when you combine the light speed barrier with the vast distances of space, it seems (so far) highly unlikely that intelligent species will ever cross eachother.

Eventually, with the universe expanding, we will be farther and farther away from eachother, assuming we escape this planet at all before the sun goes poof.

auto-da-fe

Just to show how incredibly bored I am, I just figured out that by counting 2 numbers ever second, 24 hours a day, it would take 4,439,370,877,727,042.11 years to count to 70 sextillion.

Good lord I am bored today.

Arken

I think it is very probable that there is some extra-solar life out there somewhere. With that many stars, I think it is likely that at least one other would have similar enough conditions to Earth that complex protiens would begin to form leading to DNA, etc... but how many is another question. Although the Drake Equation is fairly useless in terms of calculating numbers, it can give you pause when you think of how unlikely life might be. Think about it... from what we know at this time, you need:

• A stable main sequence yellow dwarf star.
• A planet in a stable orbit in the star's 'habitable zone' which is not so small it can't keep an atmosphere and not so large that it is a gas giant.
• Several sizable outer planets to deflect comets, meteors and other space debris from constantly bombarding the inner planets.
• A lot of carbon.
• A lot of water in liquid form.

We, of course, have absolutely no idea how many planets there are like that, let alone how many actually have life which develops enough intelligence to enable them to communicate with us but it could be extremely few.

Amaranth

Why is it that any time someone mentions alien life, some detractor immediately converts it into "advanced, hyper-intelligent space faring life!"

A quick note: Bacteria is alive.

Thanks.

Amaranth

Arken

Probably because we don't have a chance at finding extrasolar bacterial life any time in the forseeable future. The only chance of proving it is by finding radio signals (or more recently Optical SETI but I think that's not very likely to turn up anything) which requires intelligent life capable of using radio technology as a communication medium.

contracycle

Because the Fermi Paradox is based on the Drake Equation, which specifically includes the specification that life be technical.

Drakes equation nevertheless knocks out large numbers of technical species as committing technical suicide (nuclear war, global warming, etc). The point was to identify the number of technical species which should be a) alive and b) visible now.

The amount of non-technical life expected would be orders of magnitude more probable.

http://www.seti.org/science/drake-bg.html