Why We Haven’t Met Any Aliens

Re:Why We Haven’t Met Any Aliens by ck2 on Thursday December 22, 2011 @03:41AM (#3380895)

Finding earth (or another earth-like planet with people) would be like finding a particular particle of sand on a beach.

The universe is mind numbingly big - try to imagine how big and then quadruple that size and you are still wrong.

Just the observable universe is nearly 50 BILLION lightyears in each direction (there could be more and it's expanding).

(remember the deficit/debt demonstrations of "million" vs "billion")

We are trying to observe the equal of the other side of the world with optical and radio telescopes but essentially the best observations we can make out are just at the range of the doorframe to our home.

What if there is other human-like life but it's a million lightyears away - it's all but useless to us to even find out, they are long gone by the time their light and radiowaves ever get to us (and visa-versa). Now realize the nearest other galaxies are SEVERAL million lightyears away.

Try this on for size http://www.youtube.com/watch?v=9BjHvwSvpOw

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Re:Why We Haven’t Met Any Aliens by extension on Thursday December 22, 2011 @04:15AM (#3380955)

We don't need to find a particular grain of sand, we just need to find a grain of sand that's a particular shape or color. How rare such grains are is the big question. Everything we know tells us that they should be everywhere, but they aren't.

We can see for 93^h^h47 billion light years in all directions. That's a pretty big ball-o-space. Plenty to observe.

And if we find ETI, even at distances that preclude ever interacting with them, it will still be the most amazing thing to ever happen in all of human history.

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Re:Why We Haven’t Met Any Aliens by ck2 on Thursday December 22, 2011 @04:25AM (#3380974)

What if we are not just observing the wrong places but the wrong time.

Our observations are millions of years old.

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Re:Why We Haven’t Met Any Aliens by extension on Thursday December 22, 2011 @04:57AM (#3381035)

They are millions of light years away, but there is no absolute time frame in which our observations could be called "old" or "new". You can choose to think of far away things as "the past", if you like. But the point is, that doesn't make it any less cool.

EDIT: Actually, I missed your point, which was that far away things have less history in which intelligence could evolve. This is true, but the amount of history we can observe is still staggeringly large. Far too big to eliminate the paradox.

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Re:Why We Haven’t Met Any Aliens by ck2 on Thursday December 22, 2011 @05:31AM (#3381100)

You only have to miss the right time period by several thousand years to miss signs of (intelligent) life.

Someone remotely viewing earth with just a 10k year delay would not be able to measure signs of human life.

They would see exactly what we see elsewhere - nice possibly life-supporting planets, but no signs of any functionality.

Now realize we aren't just missing 10k years but 1000k years (at best).

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Re:Why We Haven’t Met Any Aliens by aamar on Thursday December 22, 2011 @04:39AM (#3380997)

Nit: 47 billion light-years in all directions; 93 billion light years is the diameter.

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Re:Why We Haven’t Met Any Aliens by mojuba on Thursday December 22, 2011 @04:12AM (#3380947)

Organic life can be detected in the emission spectrum of even the most distant objects, without establishing any contact. In fact we can theoretically detect life at very early stages. But we haven't detected anything yet, which makes the Fermi paradox even more valid (and chilling).

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Re:Why We Haven’t Met Any Aliens by ck2 on Thursday December 22, 2011 @04:20AM (#3380962)

The observations we are making are millions of years old - what if in 100k years those same analysis we do now suddenly show life.

We are not just looking at the wrong places, we are looking at the wrong times.

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