Alien life is virtually certain

[mistermack]

Just have a look at the Wikipedia page for Extrasolar planets :
http://en.wikipedia.org/wiki/Exoplanet

The latest estimates for planet numbers just in the Milky Way are mind-boggling.
17 billion Earth-sized planets
250 billion planets altogether

And that doesn't count the huge numbers of moons that these planets will have going round them.
If a moon has liquid water long-term, it can evolve life.

I haven't seen numbers like this before, but the estimates have been rising dramatically, as they analyse data coming in from the Kepler mission. Unfortunately, Kepler is out of action now, but they have only worked on a tiny fraction of it's data, so the discoveries and estimates will keep coming

It would be nice if the world found the money to send up another Kepler. Maybe that would be a good project for the world to come together to fund.

[klr]

Hello, Drake Equation ...

[Ian]

...followed by the Fermi Paradox...

[klr]

End of thread.

[mistermack]

This is no time for Anatidaean mathematics, it's serious.
Anyway, there is no paradox. People just don't understand the distances involved.
And just because alien life is virtually certain, that doesn't mean that intelligent alien life, capable of sending signals across space, is equally certain.
We humans are so freakish that if it wasn't for us, the most intelligent creatures on Earth would be chimps, or dolphins or parrots.
Not much chance of scientific advances from that lot. Chimps haven't evolved much more intelligence than their ancestors six million years ago, while humans became us from the same ancestor in the same period.

It might be the general rule that intelligence hits a brick wall, usually, and we are the one exception in many billions.

[cronus]

I prefer the waterhole hypothesis. Why is the hydrogen band silent? Why is the waterhole silent?

[Ian]

This is no time for Anatidaean mathematics, it's serious.
Anyway, there is no paradox. People just don't understand the distances involved.
And just because alien life is virtually certain, that doesn't mean that intelligent alien life, capable of sending signals across space, is equally certain.
We humans are so freakish that if it wasn't for us, the most intelligent creatures on Earth would be chimps, or dolphins or parrots.
Not much chance of scientific advances from that lot. Chimps haven't evolved much more intelligence than their ancestors six million years ago, while humans became us from the same ancestor in the same period.

It might be the general rule that intelligence hits a brick wall, usually, and we are the one exception in many billions.

Those are all factors which may explain the paradox. There are others. Personally I like the Zoo Hypothesis.
http://en.wikipedia.org/wiki/Zoo_hypothesis

[mistermack]

Those are all factors which may explain the paradox. There are others. Personally I like the Zoo Hypothesis.
http://en.wikipedia.org/wiki/Zoo_hypothesis

It's all perfectly possible. But I still prefer the brick wall theory that I just made up.
Humans, for example, evolved to this point. But now that we have most of the other species under our control, we have stopped evolving more intelligence. So we actually HAVE hit a brick wall, but we got to this stage of scientific ability, before we did.
If we'd hit the brick wall earlier, we might never have developed anything more useful than the bow and arrow.
You only need to reach a point where more intelligence doesn't give a greater survival benefit, and the evolution of the brain will stop there.
That seems to have happened to the Chimps, the Orangutans and the Gorillas. In fact, they have been losing out, to Monkeys, historically. But not with us.

[Coito ergo sum]

I like to think that this is true. However, we just don't know how likely it is for the conditions to exist that will allow what we view as "life" to arise. How common is it? Are we an extreme rarity, that can pop up maybe once in a universe of 1.6 trillion stars? One in 1.6 trillion? 2 in 1.6 trillion? Or whatever. Maybe it's 1 in 10 star systems have life, maybe one in 100, or one in 1000 or one in one trillion. What's the basis for concluding it's closer to one than another?

I think we just need more data. The thing that nags me is that we haven't even found one good piece of evidence that life ever existed anyone else in this solar system. We seem quite the anomaly.

Obviously, I have no idea. But, I don't think that the mere number of "earth size" planets (which is a huge range, by the way) tells us anything.

[cronus]

When the universe was a much smaller place and interstellar plus intergalactic travel were feasible any civilizations that erupted big in those early days would become like Google or Apple and they'd be dominant brands and decide what to do with potential competitors. Those with nothing to offer would face obliteration, those would only become like free-loaders and time-wasters. Those that had developed anything 'new' would be bought out in some way and welcomed as subsidiary partners since they'd shown potential. Earth is being observed if they are out there with anything like a multi million year old civilization. Most likely by a 'subsidiary partner' of the big guys at the top of the ET food chain. If the big guys become bored with our telly and give the word expect comets.

[pErvinalia]

Inter-galactic capitalism!

[mistermack]

Well, it took 4.7 billion years, for Earth to evolve a species like us.
The universe would have been pretty big by the time it was that old.

But our solar system needed previous big stars to burn out, and explode as supernovas, otherwise the heavier elements wouldn't have been available, to make rocky planets, or animal bodies.

So for practical purposes, I would guess that the Universe couldn't evolve life to our standard, earlier than six or seven billion years old. And we are in no state to dominate a Universe. We can't even get a man to Mars.

[cronus]

Well, it took 4.7 billion years, for Earth to evolve a species like us.
The universe would have been pretty big by the time it was that old.

But our solar system needed previous big stars to burn out, and explode as supernovas, otherwise the heavier elements wouldn't have been available, to make rocky planets, or animal bodies.

So for practical purposes, I would guess that the Universe couldn't evolve life to our standard, earlier than six or seven billion years old. And we are in no state to dominate a Universe. We can't even get a man to Mars.

The early universe was well ordered ie it had structural lumps and there'd be hot spots of heavier material, possibly close to galactic cores or quaser activity, where heavier elements would be wandering around earlier and possibly far earlier?

[mistermack]

The early universe was well ordered ie it had structural lumps and there'd be hot spots of heavier material, possibly close to galactic cores or quaser activity, where heavier elements would be wandering around earlier and possibly far earlier?

I don't think it works like that.
For heavy elements to appear, you need a giant star to burn out, and explode as a Supernova. This process is quicker, the bigger the star, but it's likely to need to happen several times, before enough heavy elements are around to produce planets etc.
I'm just guessing it would take a couple of billion years after the big bang, before something like our solar system could happen. It might have been a lot more, or a lot less.

[cronus]

The early universe was well ordered ie it had structural lumps and there'd be hot spots of heavier material, possibly close to galactic cores or quaser activity, where heavier elements would be wandering around earlier and possibly far earlier?

I don't think it works like that.
For heavy elements to appear, you need a giant star to burn out, and explode as a Supernova. This process is quicker, the bigger the star, but it's likely to need to happen several times, before enough heavy elements are around to produce planets etc.
I'm just guessing it would take a couple of billion years after the big bang, before something like our solar system could happen. It might have been a lot more, or a lot less.

Should think there'll be a goldilocks time long gone where distances and star formations along with their elements were spot on for intelligent space life to flourish. The show is over where/when we are.