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Are We Alone?


thanatos355
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Most of us are not arrogant, just insolent. We can't be the only ones in the galaxy. Improbable. There's to much evidence to the contrary.

 

Just because some other people don't share your oppinions doesn't make them arrogant or insolent or stupid or otherwise.

 

Their oppinion is their bussiness as is yours is yours.

People can have oppinions.

 

 

And there is no "evidence" , only speculation; on both sides.

 

So either oppinion may or may not be correct. Still a good chance for either of them untill one is proven wrong or right. B)

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And there is no "evidence" ' date=' only speculation; on [b']both[/b] sides.

 

So either oppinion may or may not be correct. Still a good chance for either of them untill one is proven wrong or right. B)

 

Think about that for a second. Hypothesize briefly that there are no other life forms in the cosmos. Then the only way to prove that we are alone would be to visit every star system and planet. Not likely. If we are alone, the question will never be answered.

 

OTOH, contact would definitely prove that we are not alone.

 

Meanwhile, SETI has not turned up any conclusive evidence of radio using species. That lets us set an upper bound on the density of radio using species in our neck of the woods. It's lower than most expected.

 

The discover of extra-solar planets in recent years has demonstrated that our solar system is not the only layout. Most of the discovered planets are gas giants in close orbits with their stars. When I took astronomy in 1983, the existence of gas giants in tight orbits was considered highly unlikely.

 

It may be that the conditions for radio using civilizations are actually quite rare. Many scientists now believe that without lunar tides, life may not have gotten started on earth.

 

Our moon is unique in the solar system. It was formed about 4.5 x 10^9 years ago (I could say Billion, but this is an international bunch, and an American Billion is 1,000 times smaller than an English Billion), when the earth was only a few tens or hundreds of years old.

 

The formation of the moon perplexes a lot of scientists. A recent paper suggests that a mars-sized planet accreted at either our L4 or L5 point. Passing asteroids perturbed its orbit so that it entered a horshoe orbit, slowly swinging towards earth. Eventually, it impacted with a low angled parabolic trajectory at about 150 m/s (very, very SLOWLY).

 

This impact caused the heavy elements to settle into the earth and the lighter ones to be ejected. The ejecta coalesced to form the moon.

 

This is obviously a rare occurrence. We don't see any other planets that share their orbits with other significant bodies at the L4 or L5 points. Having a mars-sized planet perturbed just enough to splash into the earth and eject material for the moon, without destroying both bodies required a low angle of impact and a very slow velocity. A higher velocity or a greater impact angle would have destroyed both (perhaps that's how the asteroid belt formed).

 

If tidal forces helped to form the first life, then life itself may be quite rare. Even then, a magnetar burst or supernova can cause extinction.

 

Once you evolve into sentient beings, you've got the problem of whether the species is aquatic or land-based. Cut the chances by another 50%.

 

Then, the development of modern civilization would have been highly unlikely had Eurasia not trended east-west and occupied a subtropical niche. We wouldn't have had the selection of crops and animals to domesticate. (Read Jared Diamond's Guns, Germs, and Steel).

 

There may be plenty of sentient beings out there, living on land, but who never got civilized and developed radio. Or, they may have, but modern societies are highly unstable, and subject to self-destruction, either through warfare or environmental collapse. What if the average existence time for a radio society is only a few hundred years? (The instability part, see Diamond's book, Collapse)

 

We don't know what the frequency of rocky planets at a liquid water orbit are. We don't know how likely a Mars type destruction of atmosphere is, or a runaway greenhouse effect, a la Venus is. We can surmise that a significant size moon is 12.5% at best, for those rocky planets in a liquid water orbit.

 

Then, the evolution of a sentient species ... what's the frequency of that? 100% 50% 10% 1%? And those species cannot be aquatic, or you won't get any radio signal. Potentially you've lost between 25% and 75% of sentient species to aquatic life.

 

These species can have a very sophisticated civilization, but it's not guaranteed to develop modern technology. Let's say 50% do - how many modern societies make the transition from competetive-destructive to cooperative-sustainable? Ours hasn't yet, although I see some hopeful signs. It is conceivable that modern society will collapse within the next 50 to 100 years.

 

We've just about reached the peak of global oil production. We nearly had global thermonuclear war during the Cuban Missile Debacle. We came inches from it. Our only example tells us that a modern society may not be viable for very long. Potentially, 0.005% of the species existence!!!

 

All these factors MAY combine to make contact and/or detection quite rare, even if sentient life isn't rare.

 

And that's without drifting away from what we know about ourselves. What if a sentient society communicates telepathically? It may never need radio, and thus be undiscoverable.

 

Not meaning to be negative here, but lots of stuff to ponder. Life may be rare. Sentient life is certainly rarer. Developing a modern, technological society may be quite a bit rarer. And that may burn out in an all-too-brief instant of time.

 

Or, developing space-faring ability may be the result of a Trek-like planetary unification, a society that has resolved its ugly issues - and they may be out there, watching the savages on Earth, taking notes, but being careful not to be seen!

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And there is no "evidence" ' date=' only speculation; on [b']both[/b] sides.

 

So either oppinion may or may not be correct. Still a good chance for either of them untill one is proven wrong or right. B)

 

Think about that for a second. Hypothesize briefly that there are no other life forms in the cosmos. Then the only way to prove that we are alone would be to visit every star system and planet. Not likely. If we are alone, the question will never be answered.

 

OTOH, contact would definitely prove that we are not alone.

 

Meanwhile, SETI has not turned up any conclusive evidence of radio using species. That lets us set an upper bound on the density of radio using species in our neck of the woods. It's lower than most expected.

 

The discover of extra-solar planets in recent years has demonstrated that our solar system is not the only layout. Most of the discovered planets are gas giants in close orbits with their stars. When I took astronomy in 1983, the existence of gas giants in tight orbits was considered highly unlikely.

 

It may be that the conditions for radio using civilizations are actually quite rare. Many scientists now believe that without lunar tides, life may not have gotten started on earth.

 

Our moon is unique in the solar system. It was formed about 4.5 x 10^9 years ago (I could say Billion, but this is an international bunch, and an American Billion is 1,000 times smaller than an English Billion), when the earth was only a few tens or hundreds of years old.

 

The formation of the moon perplexes a lot of scientists. A recent paper suggests that a mars-sized planet accreted at either our L4 or L5 point. Passing asteroids perturbed its orbit so that it entered a horshoe orbit, slowly swinging towards earth. Eventually, it impacted with a low angled parabolic trajectory at about 150 m/s (very, very SLOWLY).

 

This impact caused the heavy elements to settle into the earth and the lighter ones to be ejected. The ejecta coalesced to form the moon.

 

This is obviously a rare occurrence. We don't see any other planets that share their orbits with other significant bodies at the L4 or L5 points. Having a mars-sized planet perturbed just enough to splash into the earth and eject material for the moon, without destroying both bodies required a low angle of impact and a very slow velocity. A higher velocity or a greater impact angle would have destroyed both (perhaps that's how the asteroid belt formed).

 

If tidal forces helped to form the first life, then life itself may be quite rare. Even then, a magnetar burst or supernova can cause extinction.

 

Once you evolve into sentient beings, you've got the problem of whether the species is aquatic or land-based. Cut the chances by another 50%.

 

Then, the development of modern civilization would have been highly unlikely had Eurasia not trended east-west and occupied a subtropical niche. We wouldn't have had the selection of crops and animals to domesticate. (Read Jared Diamond's Guns, Germs, and Steel).

 

There may be plenty of sentient beings out there, living on land, but who never got civilized and developed radio. Or, they may have, but modern societies are highly unstable, and subject to self-destruction, either through warfare or environmental collapse. What if the average existence time for a radio society is only a few hundred years? (The instability part, see Diamond's book, Collapse)

 

We don't know what the frequency of rocky planets at a liquid water orbit are. We don't know how likely a Mars type destruction of atmosphere is, or a runaway greenhouse effect, a la Venus is. We can surmise that a significant size moon is 12.5% at best, for those rocky planets in a liquid water orbit.

 

Then, the evolution of a sentient species ... what's the frequency of that? 100% 50% 10% 1%? And those species cannot be aquatic, or you won't get any radio signal. Potentially you've lost between 25% and 75% of sentient species to aquatic life.

 

These species can have a very sophisticated civilization, but it's not guaranteed to develop modern technology. Let's say 50% do - how many modern societies make the transition from competetive-destructive to cooperative-sustainable? Ours hasn't yet, although I see some hopeful signs. It is conceivable that modern society will collapse within the next 50 to 100 years.

 

We've just about reached the peak of global oil production. We nearly had global thermonuclear war during the Cuban Missile Debacle. We came inches from it. Our only example tells us that a modern society may not be viable for very long. Potentially, 0.005% of the species existence!!!

 

All these factors MAY combine to make contact and/or detection quite rare, even if sentient life isn't rare.

 

And that's without drifting away from what we know about ourselves. What if a sentient society communicates telepathically? It may never need radio, and thus be undiscoverable.

 

Not meaning to be negative here, but lots of stuff to ponder. Life may be rare. Sentient life is certainly rarer. Developing a modern, technological society may be quite a bit rarer. And that may burn out in an all-too-brief instant of time.

 

Or, developing space-faring ability may be the result of a Trek-like planetary unification, a society that has resolved its ugly issues - and they may be out there, watching the savages on Earth, taking notes, but being careful not to be seen!

 

Your Hypothisis is quite vast there... you have quite the mind for generating these ideas.

 

I'm affraid to say

Hypothesizeation is all we have. However doesn't mean dreaming or having a dream about it is wrong.

 

by the way I voted "No" to the are we alone vote.

 

You see I watched "Contact" the movie and its quite the movie to watch mind you.

 

We still need to remember we have eachother B)

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There has to be other life out there. The only logical reason as to why we have not established a dialogue with any other species would be due to the fact that we as a species have not completely grown out of our infantile ways. We tend to be too hostile with others of our own kind. Any species that could or might check in on us would find that we lack in certain social behaviors that are an acceptable norm in their society. That, and the fact that we haven't achieved a faster-than-light method of travel yet. We really need to overcome our differences as a global community to achieve these goals... The question is HOW?

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We just recently figured out how to make a cloaking device for our spaceships!

 

......Unfortunately, we don't have the spaceships yet!? Oh well......Star Trek is becoming more real by the day.

 

:stare:

 

Perhaps in the grand scheme of things, the fictional Star Trek must die, so that the real life Star Trek can become a reality?

 

In any event, our little solar system is nestled at the very tip of one of the "arms" or "spirals" of our galaxy. Just to reach the center of our galaxy reques several lifetimes. Just in our galaxy alone, there is an over abundance of "Class M" type planets.

 

......Planets like Earth.

 

If we factor in the as yet un-numbered amount of galaxies in the Universe, the idea that we are alone becomes laughable.

 

Concidering the age of our galaxy alone, let alone the age of the Universe, it's a fair chance that many of the space-farring races are considerably older than we are, and quite capeable of keeping from being seen.

 

......If we can figure out how a cloaking device works, you can bet they already have one!!

 

:stare:

 

As Star Trek predicts, kind & noble races will not approach us until we ourselves become a space-farring race. But to say that all these races will be friendly is foolishness. It is upon us to be cautious as we venture forth from our little world.

 

:stare:

 

 

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American Billion is 1' date='000 times smaller than an English Billion), when the earth was only a few tens or hundreds of years old. [/quote']

 

?????

 

1,000 - thousand

1,000,000 - million

1,000,000,000 - billion

1,000,000,000,000 - trillion

 

thats what i always thought because i work in metric everything goes up in thousands, this is very confusion as i live in the uk.

...

ah it seems that the bi suggests 2 as in power of and tri suggests 3 as in power of.

so billion means million squared which is 1,000,000,000,000. and a trillion is a million cubed which is 1,000,000,000,000,000,000..

 

so.. when in europe i should use the words how they are actually meant from the words meaning, and in the u.s i should use the words in the way i thougth they ment.

but in the u.k where my friends seem to be split about the matter, i still have no idea whats going on...

 

hmm i think i'll go with 10^12 billion as thats what the word suggests.

 

i'll have to keep an eye out for this when i'm out of uni or huge amounts of money will be wasted as buildings collapse and roads are way to big

 

thanks for bringing this to my attention elderbear.

and sorry everyone for the out of topic post

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Where did you get the information on this from' date=' Von? I'd be interested in reading up on it...[/quote']

 

Engineers devise invisibility shield

 

space.jpg

 

The idea of a cloak of invisibility that hides objects from view has long been confined to the more improbable reaches of science fiction. But electronic engineers have now come up with a way to make one.

 

More.......

 

http://www.nature.com/news/2005/050228/full/050228-1.html

 

:stare: :stare: :stare:

 

 

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Your Hypothisis is quite vast there... you have quite the mind for generating these ideas.

 

I'm affraid to say

Hypothesizeation is all we have. However doesn't mean dreaming or having a dream about it is wrong.

 

by the way I voted "No" to the are we alone vote.

 

You see I watched "Contact" the movie and its quite the movie to watch mind you.

 

We still need to remember we have eachother B)

 

Yeah, I can get long winded sometimes, and my brain seems to never shut off (yeah, I know, they've got meds for that!) - not that it always spews quality stuff!

 

In science, we form a hypothesis. Then we try to disprove its opposite - the null hypothesis. In this case, the null is "We are alone." Any contact will disprove it - even if it's just ancient radio signals. Unfortunately, the work that has been done to disprove it hasn't born fruit yet, after several decades. All that does is tell us that we don't have a ton of neighbors who use radio.

 

But yeah, I'd like to think that we're not alone and that we even have the possibility for communication with other intelligent life forms. It's a gut thing, not a science thing for me.

 

I especially like your concluding thought. We're not alone, we have each other. IMHO, that's one of the biggest points of all the various Treks: Humans have figured out how to get along, to not be so unnecessarily alone. Kind of ironic that after that happens, we've got contact with other sentient species!

 

If you enjoyed Contact, you really should read the book. It was so much deeper, far more interesting. BTW, when Jodi Foster is at the Arecibo Observatory in Contact, she sleeps with Matthew McConahey. That was my room for a couple of weeks. B) Unfortunately, she wasn't in it. :( Fortunately, John Hinckley doesn't know I was there. :o

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There has to be other life out there.

 

No. There really doesn't have to be any other life than life on earth. I admit that it would be highly improbable if earth was the only place and time in the universe with life. But it could be.

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American Billion is 1' date='000 times smaller than an English Billion), when the earth was only a few tens or hundreds of years old. [/quote']

 

?????

 

1,000 - thousand

1,000,000 - million

1,000,000,000 - billion

1,000,000,000,000 - trillion

 

thats what i always thought because i work in metric everything goes up in thousands, this is very confusion as i live in the uk.

...

 

Then you know better than I. I'd heard that it's 10^12 in UK and 10^9 in USA.

 

Scientific notation has the benefit of clarity. Speaking fo clarity, I meant that the earth was only a few tens or hundreds of MILLION years old. I dropped a factor of 10^6. :o To balance this out, the universe should soon increase my paycheck by a factor of 10^6 (and hopefully, not my TAXES!!!)

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We just recently figured out how to make a cloaking device for our spaceships!

 

Engineers devise invisibility shield (Paradoxically, this title means that engineers have figured out how to protect us against the invisible!)

 

Pendry warns, however, that the concept as it stands is "no magic cloak", because it would have to be delicately tuned to suit each different object it hides. Perhaps even more of a drawback, he points out, is the fact that a particular shield only works for one specific wavelength of light.

 

An object might be made invisible in red light, say, but not in multiwavelength daylight.

 

And crucially, the effect only works when the wavelength of the light being scattered is roughly the same size as the object. So shielding from visible light would be possible only for microscopic objects; larger ones could be hidden only to long-wavelength radiation such as microwaves. This means that the technology could not be used to hide people or vehicles from human vision.

 

Sorry, Von, no cloaking device yet! And this technology allows light to pass through an object. Thus, we'd need something else to cloak a starship. And, we'd need it to be RF and near-visible spectrum cloaking, otherwise radars or CCD imagers in IR or UV ranges could see it.

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In this case' date=' the null is "We are alone." Any contact will disprove it - even if it's just ancient radio signals. Unfortunately, the work that has been done to disprove it hasn't born fruit yet, after several decades. All that does is tell us that we don't have a ton of neighbors who use radio. [/quote']

 

I think I'm safe in saying that if they have a communications system, it's not radio!

 

:p

 

....Radio takes too long to cover great distances.

 

:stare:

 

 

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We just recently figured out how to make a cloaking device for our spaceships!

 

Engineers devise invisibility shield (Paradoxically, this title means that engineers have figured out how to protect us against the invisible!)

 

Pendry warns, however, that the concept as it stands is "no magic cloak", because it would have to be delicately tuned to suit each different object it hides. Perhaps even more of a drawback, he points out, is the fact that a particular shield only works for one specific wavelength of light.

 

An object might be made invisible in red light, say, but not in multiwavelength daylight.

 

And crucially, the effect only works when the wavelength of the light being scattered is roughly the same size as the object. So shielding from visible light would be possible only for microscopic objects; larger ones could be hidden only to long-wavelength radiation such as microwaves. This means that the technology could not be used to hide people or vehicles from human vision.

 

Sorry, Von, no cloaking device yet! And this technology allows light to pass through an object. Thus, we'd need something else to cloak a starship. And, we'd need it to be RF and near-visible spectrum cloaking, otherwise radars or CCD imagers in IR or UV ranges could see it.

 

Well, hopefully we wont be as sneaky as the star trek romulans if we ever get a cloak thing going for ships

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