Why has no one ever contacted earth?

[Mr Flibble]

I read a good book about this subject a little while ago called 'The Eerie Silence'. It addresses many of these hypothesis of the probability of intelligent life existing elsewhere, what form they may take and the chances of them making contact.

Aside from the problems of time and distance, a couple of the more interesting ideas in the book were the presence of cosmic filters and machine life-forms.

Cosmic filters effectively wipe out entire species before they become capable of interstellar travel. Cosmic filters may take the form of comet impacts, or nuclear war following discovery of the splitting of the atom, or killer pandemics, social disintergration, etc. Have we passed ours yet or is it still to come?

One of the most wierd concepts in the book was thoughts on the types of lifeform that would be most physically able for interstellar travel. With the durability and long-life of machines which never die because parts can forever be replaced and serviced, life-forms may have to undergo some sort of evolution where its intelligence passes from the biological brain into a machine which then acts as a safer and more durable repository. Its life Jim...........

I think the odds are in favour of intelligent life being out there but the time and distance is too vast for contact.

[Dazzio]

If I remember my history lessons right, the first televised broadcast was a well known Austrian known as Adolf Hitler opening the 1936 Olympic games. Then a few years later... Well we all know what happened there. If you saw that kinda stuff, would you really want to make contact with us? Let's be honest here...

I think the film "Contact" depicts exactly what would happen if there was an signal found by SETI.

I personally believe there is life out there, but the vast distances/time involved would make ET think "screw that for a laugh, I want a beer instead..."

Dazz

[Catanonia]

They probably have contacted earth, we just don't know about it or someone hides the truth. But if we keep destroying the earth and polluting space. They will soon see us as a threat to there universe, and destroy us all. It takes a certain kind of a civilization to travel vast distances in space so do u think those aliens act like us, or live like us, i am sure they dont, because they know if they were like us there civilization wouldn't be around for very long, if you think about it. were newborns in space.

This is what I love about humans, ignore everything and make it up including the forbidden R or G words.

Yes I am sure there is life out there, infact positive about it, but as the OP says,

"Why has no one ever contacted earth"

The numbers speak for themselves.

[thesatanbug]

Maybe we are the first. Just another one of the universe's ad-hoc experiments. If it works out more will follow. If we muck it all up, the idea will get scraped as a bad lot.

[Tadakun]

Maybe we are the first. Just another one of the universe's ad-hoc experiments. If it works out more will follow. If we muck it all up, the idea will get scraped as a bad lot.

By saying this you are saying that there is a higher power/intelligence/being aren't you?

[Catanonia]

By saying this you are saying that there is a higher power/intelligence/being aren't you?

Lol nice

[Holderness]

Maybe it's because we are not yet in the intergalactic telephone directory yet! Or we are ex directory!!

[saturn5]

By saying this you are saying that there is a higher power/intelligence/being aren't you?

Yep,Prof Brian Cox:evil6:

[Renaissance2010]

We may have been visited many years ago & have probably now incorporated this into religious beliefs, or maybe intelligent life elsewhere is so different to our concepts that it we wouldn't even recognise it if it where amongst us.

[pook]

On a more scientific note, as far as we know, nothing can travel faster than light, and seeing as we've only been transmitting radio into space at a level that could travel inter-stellar for around 70 years, there aren't THAT many stars within range to even the odds of intelligent life receiving the signal. Even if they have, the returned greeting would take an equal amount of time to be returned to us, so maybe in a 100 years or so, we WILL get a reply.

There's still the problem of them actually getting here though.

Even if it was possible... why would you want to attract the attention of others? Why assume they'll be benign? Maybe they'll just arrive, conquer us, and mine us of out resources and sod off again After all, that's what we have done to new found lands so far in our history.. why assume more intelligent life will be more magnanimous?

[thesatanbug]

By saying this you are saying that there is a higher power/intelligence/being aren't you?

No. Anything but.

[vulcan]

as far as we know, nothing can travel faster than light

Two points here. 'as far as we know' excludes the overwhelming mass of stuff we don't know. You have to accept that we don't know much - but then, we don't know how much we don't know.

tachyons are supposed to travel faster than light. They have no mass so e=mc2 is not violated. If the 'advanced' race were, sensibly, using tachyons (or something better) for communications, it would all go over our heads as we have no such technology.

Who says we haven't been contacted? 'As far as we know' we haven't been contacted - but that's not very far! They could be shouting their heads off and we are blissfully unaware.

Is there intelligent life on the planet Earth?

[Brainstorm]

Maybe they didn't leave, after wiping the dinosaurs out, we found this place habitable.

Or maybe the way we send and receive data is different to the way the 'little green men' do it

[pook]

Two points here. 'as far as we know' excludes the overwhelming mass of stuff we don't know. You have to accept that we don't know much - but then, we don't know how much we don't know.

All true of course, but given the fact that there's no evidence of us being visited, and coupled with the huge likelihood that there is life on other worlds, it would suggest that this inability to travel faster than light is quite a common problem. I know that if I could travel faster than light, I'd be visiting as many different worlds as I could.

tachyons are supposed to travel faster than light. They have no mass so e=mc2 is not violated. If the 'advanced' race were, sensibly, using tachyons (or something better) for communications, it would all go over our heads as we have no such technology.

But... if they are replying to our signals.. they'd reply in the same format they received it in.

[Mr Spock]

Yes, there is intelligent life out there. They regularly use warp drive to travel hundreds of light years to Earth where they like to buzz crops and interfere with cows.

The Federation seems to have lapsed a bit on the prime directive.

[Nillchill]

Has anyone ever considered the amount of footage that leaks from this planet in the form of radio signals and video signals, and Race of being worth its salt would be able to decode this and see that we are alien hating, powerful beings capable of destroying numerous alien invasions and visitors with the minimum of technology.

If you saw that would you want to visit??!!!!

[Dazzio]

Has anyone ever considered the amount of footage that leaks from this planet in the form of radio signals and video signals, and Race of being worth its salt would be able to decode this and see that we are alien hating, powerful beings capable of destroying numerous alien invasions and visitors with the minimum of technology.

If you saw that would you want to visit??!!!!

I think if they to actually see u's in any from any films they'd realise that our colds and flu will kill them all. Fear our sneezes!!!

Dazz

[Talitha]

Why has no one ever contacted earth?

Actually, they were on their way to pay us a visit but got lost.

A back-seat driver insisted they 'turn left at Orion'.

(i'll get my coat....)

[Photosbykev]

Why has no one ever contacted earth?

Actually, they were on their way to pay us a visit but got lost.

A back-seat driver insisted they 'turn left at Orion'.

(i'll get my coat....)

I blame the author of "Turn Left at Orion" as well, if it was called "Straight on to Earth" we would of been over run by aliens years ago.

ps the real answer is in my signature

[michael.h.f.wilkinson]

Yes, there is intelligent life out there. They regularly use warp drive to travel hundreds of light years to Earth where they like to buzz crops and interfere with cows.

The Federation seems to have lapsed a bit on the prime directive.

And of course there are Teasers (rich kids with nothing better to do than land on planets next to some poor sod who no-one is ever going to believe and strut around with antennae on their heads, making silly beep-beep noises).

And of course there is cricket, which is considered very bad taste by everyone else out there.

(doffs hat to Douglass Adams, sorely missed)

[michael.h.f.wilkinson]

Two points here. 'as far as we know' excludes the overwhelming mass of stuff we don't know. You have to accept that we don't know much - but then, we don't know how much we don't know.

We do know quite a bit by elimination. First, electromagnitism is a plausible way to communicate because it is cheap, and has long range. The other forces are either too short range (weak and strong: by a factor of 10^20 at least) or too weak (gravity). To send a message by radio I need chase electrons up and down some wire, and with sufficient power (in the tens of Watt range) I can already do interplanetary communication. The rays can easily be tuned, focused etc. To use gravity I need to shake a solar mass severely to be barely detectable by sensitive instruments. Thus radio communication is an obvious choice for interstellar communication, also because fibre optics get tangled when you orbit a planet . There may of course be other forces we do not know about, but these are either so short range or so weak that their effects have to date been drowned out by the forces in the experiments so far.

tachyons are supposed to travel faster than light. They have no mass so e=mc2 is not violated. If the 'advanced' race were, sensibly, using tachyons (or something better) for communications, it would all go over our heads as we have no such technology.

This is a valid option, but tachyons need imaginary rest mass, in order to have real mass when moving at tachyonic speeds. We have not found these entities yet, and there is a Nobel prize in store for anyone who does.

Who says we haven't been contacted? 'As far as we know' we haven't been contacted - but that's not very far! They could be shouting their heads off and we are blissfully unaware.

Is there intelligent life on the planet Earth?

Not according to Monty Python's "Galaxy song" (they may play that at my funeral)

[Red Coffee]

Like this theory

Has ET evolved to be discreet? An evolutionary tendency for inconspicuous aliens would solve a nagging paradox – and also suggest that we Earthlings should think twice before advertising our own existence.

As physicist Enrico Fermi argued in 1950, unless the evolution of life is unique to Earth, there must be many intelligent species out there. So why have they neither phoned home nor been detected by us?

"It's a real paradox," says Adrian Kent of the Perimeter Institute in Waterloo, Ontario, Canada.

In order to explain the Fermi paradox, Kent turns to natural selection – and suggests that it may favour quiet aliens.

Violent universe

He argues that it's plausible that there is a competition for resources on a cosmic scale, driving an evolutionary process between alien species on different planets. Advanced species, for example, might want to exploit other planets for their own purposes.

If so, the universe would be a violent place, and evolutionary selection may favour the inconspicuous – those who lay low on purpose, or who simply lack the skill or ambition to venture forth or advertise their existence.

"This is an interesting idea," says alien hunter Seth Shostak of the SETI institute in Mountain View, California. "If I let the cosmos know I exist, then I might be subject to extermination."

However, he is wary of assuming a "straitjacket" on the activities of intelligent species, who might not be able to resist the intellectual pull to develop advanced technologies detectable by others.

"If interstellar violence is possible, the bad news is that all societies are required to constrain their endeavours to activities that could never be detected at a distance," says Shostak.

Voyager danger

Kent acknowledges that his hypothesis is speculative. But he also warns that it could have real consequences for the near future: vehicles such as NASA's two Voyager probes, which are hurtling away from the solar system, may alert imperialist aliens to our existence and require retrieval, he says.

He adds that it may not take much for a truly advanced civilisation to wipe us out pretty quickly. "The hyper-advanced aliens might not have to send their interstellar battle fleet to conquer Earth," he notes. "It might only take three bored undergraduate aliens with borrowed lab equipment."

[rfdesigner]

Ok food for thought.

We have had radio technology for about 100+ years and have been pumping out into space all sorts of signals.

Now as technology increases, our use of radio waves decreases to much short distance communications at lower power.

In another 100 years we won't be pumping out so much into space. Infact it is decreasing rapidly.

So one could say that with higher technology becomes lower radiation leakage from a civilised society and hence harder to think.

we in 200 - 300 years could almost be silent to radio listeners.

So 300 years in 14 billion = very small window.

Also we might be looking at the wrong thing, perhaps we need to be looking at other forms of communication we have not invented yet.

My thoughts, I don't personally think SETI will find anything.

Actually it's worse than that.

A perfectly efficient radio communication system will look like noise, because noise is the most information rich signal you can have. All modern radio communications are tending towards noise. Look at Digital TV or DAB vs the old PAL or FM system on a spectrum analyser and you'll see a little flat topped blob of 'noise'.. go for ultra wideband as used by, shall we say, 'certain official organisations' and then you get a gigahertz or more of noise, at a very low signal level per Hz.. mostly well below the ambient signals.

No it's not radio comms I'd look for, not unless you expect to find beacons.

Derek

[Karlos]

I'm personally a 100% believer of life out in the universe, there just must be, the probability that there is life is so small but then there is us and the size of the universe, it is a very likely. We probably haven't been contacted for the same reasons we've been unable to detect life yet or get our messages heard, the universe is just so big and instruments we have so tiny we haven't looked in all places possible.

[Karlos]

Also, just to add. I saw a issue of New Scientist last year where they were explaining a message they were broadcasting in space, I think using some kind of radiowaves. Interestingly, the pictures they use in it informed the recipient information on the human race, giving an idea of our dimensions and that we are water/carbon based somehow expressed using very pixelated images.