Scientific American: If There Are Aliens Out There, Where Are They?

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Michael Watson

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Message 1755625 - Posted: 11 Jan 2016, 18:35:16 UTC
Last modified: 11 Jan 2016, 18:42:40 UTC

Assume that some version of M theory is correct, as most physicists do. Given sufficient technological development, it might be possible to cause radio waves to make detours through bulk space, re-emerging in normal space at distances much greater than light could reach in the same length of time. This would amount to effectively communicating faster than the speed of light, without actually violating the speed-of-light barrier in relativity theory.
Faster than light signaling would seem to be of great advantage, if not essential, to a galaxy-spanning civilization.

This might also have the advantage of allowing us to receive these transmissions with the technology at hand, should such a signal happen to re-emerge nearby, and so be strong enough to detect.
The problem would be deducing where and when the signals might re-enter normal space, so as to have our highly directive antennas aimed aright. Either that, or listen with an omnidirectional antenna, and hope for a strong enough signal re-entering normal space quite nearby.
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Profile William Rothamel
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Message 1755635 - Posted: 11 Jan 2016, 19:16:29 UTC - in response to Message 1755595.  

If we ever found a rocky planet with water in the habitable zone that had an atmosphere---it just might be possible to look for signs of life( or probable life ) and industrialization by analyzing the atmosphere itself.
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Michael Watson

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Message 1755646 - Posted: 11 Jan 2016, 20:21:19 UTC
Last modified: 11 Jan 2016, 20:29:27 UTC

Oxygen, water vapor, and traces of methane in combination, in an exo-planet atmosphere would be a good indication of life there. Pollutants like carbon monoxide, nitrogen oxides, and airborne particulate matter could indicate a civilization at roughly our level of development, assuming they're plentiful enough for us to detect at stellar distances.
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Message 1756457 - Posted: 15 Jan 2016, 2:16:37 UTC - in response to Message 1755646.  

Pollutants like carbon monoxide, nitrogen oxides, and airborne particulate matter could indicate a civilization at roughly our level of development, assuming they're plentiful enough for us to detect at stellar distances.

I'm guessing someone has done "back of envelope" figures on how much is needed; or, how far our own pollutants can be seen. Can anyone suggest a link for this?
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Message 1758417 - Posted: 23 Jan 2016, 0:21:33 UTC

Interesting article published in Astronomy Magazine.....
http://astronomy.com/news/2016/01/the-aliens-are-silent-because-they-are-extinct?spMailingID=24538025&spUserID=MTE2MjkxODk4MjA3S0&spJobID=723079024&spReportId=NzIzMDc5MDI0S0

The aliens are silent because they are extinct
In research aiming to understand how life might develop, scientists realized new life would commonly die out due to runaway heating or cooling on their fledgling planets.
By Australian National University in Canberra | Published: Thursday, January 21, 2016

"Life on other planets would likely be brief and become extinct very quickly, said astrobiologists from the Australian National University (ANU).

In research aiming to understand how life might develop, scientists realized new life would commonly die out due to runaway heating or cooling on their fledgling planets.

“The universe is probably filled with habitable planets, so many scientists think it should be teeming with aliens,” said Aditya Chopra from ANU.

“Early life is fragile, so we believe it rarely evolves quickly enough to survive.”

“Most early planetary environments are unstable. To produce a habitable planet, life forms need to regulate greenhouse gases such as water and carbon dioxide to keep surface temperatures stable.”

About four billion years ago, Earth, Venus, and Mars may have all been habitable. However, a billion years or so after formation, Venus turned into a hothouse and Mars froze into an icebox.

Early microbial life on Venus and Mars, if there was any, failed to stabilize the rapidly changing environment, said Charley Lineweaver from ANU.

“Life on Earth probably played a leading role in stabilizing the planet’s climate,” he said.

Chopra said their theory solved a puzzle.

“The mystery of why we haven’t yet found signs of aliens may have less to do with the likelihood of the origin of life or intelligence and have more to do with the rarity of the rapid emergence of biological regulation of feedback cycles on planetary surfaces,” he said.

Wet, rocky planets with the ingredients and energy sources required for life seem to be ubiquitous, however, as Enrico Fermi pointed out in 1950, no signs of surviving extra-terrestrial life have been found.

A plausible solution to Fermi’s paradox, say the researchers, is near universal early extinction, which they have named the Gaian Bottleneck.

“One intriguing prediction of the Gaian Bottleneck model is that the vast majority of fossils in the universe will be from extinct microbial life, not from multicellular species such as dinosaurs or humanoids that take billions of years to evolve,” said Lineweaver."

"Sour Grapes make a bitter Whine." <(0)>
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Message 1758653 - Posted: 23 Jan 2016, 14:15:43 UTC

Perhaps the sooner the current human race becomes extinct the better it will be for the galaxy and the universe.

That's a pretty dark and nihilistic statement Chris. The article is simply positing another theory as to why we're not tripping over ET on a daily basis. As you said no one can prove anything until first contact actually occurs, and then it will be MANY years, if ever, before we understand more than the mere fact of their existence.

My most fervent hopes are that when contact does occur that ET.....

1) is not so advanced that they view humanity as an infectious disease.

2) don't think we taste good.......":>)

"Sour Grapes make a bitter Whine." <(0)>
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Message 1758664 - Posted: 23 Jan 2016, 14:51:11 UTC
Last modified: 23 Jan 2016, 14:53:52 UTC

Definitely your opinion about this subject, Chris.

If I happen to watch a YouTube video showing UFO's flying in the sky, should such a thing for granted, namely that we are not alone in the universe.

If you happen to be a skeptic, or even a debunker (which I do not think Chris is), you may be willing to have such an opinion when it comes to a scientific project as a whole, without necessecarily making a thought about specific results being obtained or discoveries perhaps being made.

Some people may thing that the Universe has been created by a God with a specific purpose in mind.

We are here in order to be able to make new discoveries and at the same time getting both positive and negative experiences back in return.

Time is both past, present and right now. Whether or not you are living backwards or forwards in time, certain things are what they are supposed to be because they happen to be right so.

Time means change and if you happen to be looking at the Hubble Deep Field, you also may be able to know how things were looking millions or even billions of years ago.

In the same way as you may be able to do such a thing, you can not predict the future in a similar way.

The only thing we may be able to know is that the Universe is changing and the next day could likely bring a change to things which could be affecting our lives.
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Message 1758700 - Posted: 23 Jan 2016, 16:23:57 UTC

Chris, my point was that to wish for the extinction of something that, as far as we know, may be the rarest and most tenuous element to exist in 14 Billion years, is counter intuitive to existing at all. One unknown, London sized N.E.O. from the right direction (Chelyabinsk), and you get your wish.

No need to beg trouble..........

"Sour Grapes make a bitter Whine." <(0)>
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John D Anthony

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Message 1758738 - Posted: 23 Jan 2016, 18:40:43 UTC

One of my granddaughters asked me if I thought aliens might really exist, and I told that depends on what mood I'm in.
I've read a couple variations of the Gaian Bottleneck concept and find it very plausible. Life as we know it is incredibly tenacious and adaptive after it's well established, but while the emergence of life may be common it's long-term survival may be rare.
I intend to keep listening, however. There may be a lot of reasons we're not hearing anything now, but it'll only take ONE signal to answer the question.
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Michael Watson

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Message 1758807 - Posted: 23 Jan 2016, 21:29:06 UTC

The comparison made in the Astronomy magazine article, between Venus, Earth, and Mars is not so discouraging for the prospects for life, even intelligent life in other star systems.
If one out of three planets in our star's habitable zone can host complex life, intelligence, and a stable environment, on what basis are we to decide that this same proportion of planets is not similarly endowed in other star systems?
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Profile William Rothamel
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Message 1758877 - Posted: 24 Jan 2016, 1:06:13 UTC - in response to Message 1758807.  

The basis that I like to think of requires narrow parameter ranges of a dozen or more variables.

For instance.

Rocky planet with water
magnetic field
Circular orbit
Moon to lock a stable wobble
Tides
And the list goes on.
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Message 1759014 - Posted: 24 Jan 2016, 14:18:00 UTC

I think it is a pretty good bet that in one form or another intelligent beings exist elsewhere in our galaxy and certainly somewhere in the universe. But they are probably in the same predicament as us. All dressed up and no way to get anywhere.
Bob DeWoody

My motto: Never do today what you can put off until tomorrow as it may not be required. This no longer applies in light of current events.
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Message 1759556 - Posted: 27 Jan 2016, 3:31:17 UTC
Last modified: 27 Jan 2016, 3:32:35 UTC

And at least do not trust those numbers you might be able to come across by means of crunching for Seti@home.
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Message 1761017 - Posted: 31 Jan 2016, 14:23:39 UTC

I don't know how these numbers compare to recent ideas, but Bones said this to Kirk in a Star Trek episode I saw yesterday:

"There's a probability of 3 million Earth-like planets in our galaxy, and 3 million million galaxies in the universe."
The mind is a weird and mysterious place
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Message 1761021 - Posted: 31 Jan 2016, 14:48:48 UTC

The estimate of 3 million might be a bit light considering the discoveries of Kepler alone.

"Sour Grapes make a bitter Whine." <(0)>
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Message 1761052 - Posted: 31 Jan 2016, 17:02:15 UTC - in response to Message 1761021.  
Last modified: 31 Jan 2016, 17:02:49 UTC

Since we have yet to find a single planet that is truly Earth-like in the sense of being able to spawn and support intelligent my estimate of 5 or less in the galaxy is most likely more accurate then the estimate of 3 million and just as uncertain.

Figure out the average volume represented by each of these putative 3 million planets and then see if we have found any such planet within this distance from Earth --perhaps in the future as we search farther and farther out.
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Message 1761165 - Posted: 1 Feb 2016, 0:34:34 UTC - in response to Message 1761017.  

I don't know how these numbers compare to recent ideas, but Bones said this to Kirk in a Star Trek episode I saw yesterday:

"There's a probability of 3 million Earth-like planets in our galaxy, and 3 million million galaxies in the universe."


This distances involved with just our Solar System neighborhood are staggering. The fact that there may be others worlds like ours in other galaxies is like saying there are other worlds in other dimensions. The distances would be too vast to be meaningful.

Bob
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Message 1761637 - Posted: 2 Feb 2016, 14:01:56 UTC - in response to Message 1761547.  

The question needs to be asked, are we interested in finding ANY alien or only ones like us?

The racism we already demonstrate on just this planet should answer that question completely. Which may also be why, if they are there, they don't contact us. They don't want to have to kill us in self defense........

"Sour Grapes make a bitter Whine." <(0)>
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Michael Watson

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Message 1761662 - Posted: 2 Feb 2016, 15:30:56 UTC
Last modified: 2 Feb 2016, 15:34:20 UTC

Humans have a long history of group rivalries; dividing ourselves into into 'us' and the 'other', and fearing, hating, and/or exploiting the 'other'. It's true that this could be impeding our contact with extraterrestrial intelligences.

I find it heartening that in our time, we are beginning to question and to break down these divisions among ourselves. This trend should help prepare us for the day when we find evidence of, or make actual contact with beings from another world.
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Message 1761682 - Posted: 2 Feb 2016, 16:19:01 UTC - in response to Message 1761637.  

There is no "They" that think we are a flawed creation. So far as we now know there is no "They" within detection distance whatsoever. Time and technology may change this--at such time we may then like to speculate on their perceptions and sensitivities.

What we are hoping for and most likely to find, if "They" exist, is most probably:

A civilization who is sentient to at least the degree that we are and has learned to communicate across vast distances.

Whether or not they want to visit us will depend on if we find "Them" and how far away they are and any resulting dialog. Right now it doesn't look good for such an alien race within as far as we can monitor electronic emissions.
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