DebateGate
General Category => 3DHS => Topic started by: The_Professor on April 11, 2010, 04:53:32 AM
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THE SATURDAY ESSAY
APRIL 10, 2010.
Is Anybody Out There?
After 50 years, astronomers haven't found any signs of intelligent life beyond Earth. They could be looking in the wrong places..
By PAUL DAVIES
Fifty years ago this week, on April 8, 1960, a little-known astronomer named Frank Drake sat at the controls of an 85-foot radio telescope at an observatory in Green Bank, W.Va., and began to sweep the skies, looking for a signal from an alien civilization. It was the start of the most ambitious scientific experiment in history.
Barely an hour had passed when the equipment suddenly went wild. A loudspeaker hooked up to the giant antenna began booming and the pen recorder gyrated manically. The radio telescope was pointed at a nearby star called Epsilon Eridani. Mr. Drake was nonplussed. Surely his quest couldn't be that easy? He was right. The commotion turned out to be a signal from a secret military radar.
..The astronomer's solitary vigil lasted for a few weeks; he ran out of telescope time with little to report. Nevertheless, his pioneering effort sparked the genesis of a 50-year project known as the Search for Extraterrestrial Intelligence, now an international research program with a multimillion-dollar budget. It has included renting time on some of the biggest radio telescopes in the world—such as the 1,000-foot dish at Arecibo in Puerto Rico, featured in the James Bond movie "GoldenEye."
After five decades of patient listening, however, all the astronomers have to show for it is an eerie silence. Does that mean we are alone in the universe after all? Or might we be looking for the wrong thing in the wrong place at the wrong time?
The search for extraterrestrial intelligence, once considered a quixotic enterprise at best, has now become part of mainstream science. In the past decade or so, over 400 planets have been found orbiting nearby stars, and astronomers estimate there could be billions of Earth-like planets in the Milky Way alone. Biologists have discovered microbes living in extreme environments on Earth not unlike conditions on Mars, and have detected the molecular building blocks of life in deep space as well as in meteorites. Many scientists now maintain that the universe is teeming with life, and that some planets could harbor intelligent organisms.
Speculation about other worlds populated by sentient beings stretches back into pre-history. For millennia, the subject remained squarely in the provinces of religion and philosophy, but by the 19th century, science had become involved. Astronomical observations hinted that Mars could be a congenial abode for life, and in the 1870s the Italian astronomer Giovanni Schiaparelli fancied he could see lines on the surface of the red planet. A wealthy American writer, Percival Lowell, became fixated with the idea that Martians had built a network of canals to irrigate their parched planet, a conjecture fueled by the publication of H.G. Wells's novel "The War of the Worlds." Mr. Lowell built an observatory in Flagstaff, Ariz., specifically to map the canals and to look for other signs of Martian engineering.
Sadly for Mr. Lowell, there were no canals. Space probes sent to Mars in the 1960s found no sign of Martian engineering projects, and no sign of life either, just a freeze-dried desert bathed in deadly ultraviolet radiation.
In the next few decades, the search for radio messages from the stars was taken seriously enough to attract government funding. From 1970 to 1993, NASA spent about $78 million on projects that sought to refine Mr. Drake's trail-blazing observations, starting with a feasibility study for the construction of an array of 1,000 dishes sensitive enough to pick up routine television and radio transmissions from nearby stars. In 1992, NASA officially launched a program called the High Resolution Microwave Survey—but Congress killed it the following year, ending NASA's involvement.
Most of the funding today comes from private donations through the SETI Institute, a private nonprofit founded in 1984 in Mountain View, Calif. The jewel in its crown is the Allen Telescope Array, a $35 million dedicated network of 42 small dishes in northern California, with about $30 million of the funding contributed by Microsoft co-founder Paul Allen. The goal is to ultimately increase the network to 350 dishes. Donors on other projects have included David Packard and Bill Hewlett (co-founders of Hewlett-Packard) and Gordon Moore (co-founder of Intel).
Our own radio stations broadcast continuous narrow-band signals, that is, radio waves tuned to a sharply-defined frequency. Searches have mostly focused on something similar coming from space. The late Carl Sagan, a charismatic champion of searching for extraterrestrial signals in the 1980s, envisaged an advanced alien civilization deliberately beaming narrow-band radio messages at Earth to attract our attention. That scenario now seems very unlikely. Even optimists like Mr. Drake, still an active researcher, suppose that the nearest alien civilization would be hundreds of light years away. Because nothing travels faster than light, these hypothetical aliens would have no idea that a radio-savvy society exists on Earth yet.
A more likely sign could be a beacon, a radio source that goes bleep on a regular basis for anyone who might be listening, sweeping the plane of the Milky Way galaxy like the beam from a lighthouse. It would show up in a radio telescope as a brief pulse that repeats periodically—perhaps every few months or years.
Astronomers do occasionally detect brief radio bursts coming from space. A famous example was the so-called "Wow!" signal, recorded on Aug. 15, 1977, by Jerry Ehman using Ohio State University's Big Ear radio telescope. Mr. Ehman discovered it while perusing the antenna's computer printout, and was so excited he wrote "Wow!" in the margin. Radio pulses can arise from a variety of astronomical phenomena, ranging from spinning neutron stars to black hole explosions, but the characteristics of the Wow signal don't fit any known natural event. Nor did the pulse match a man-made disturbance. Nothing has been detected again from that part of the sky when astronomers have looked.
The logistics of building beacons have been analyzed by the astrophysicist Gregory Benford of the University of California at Irvine and his brother James Benford, an expert on high-powered beamed microwaves. The main unknown is how often a beacon would repeat, so the Benfords are urging for a systematic search to be made. It would need a dedicated set of radio telescopes, oriented to stare for years on end at a fixed patch of the sky—preferably towards the center of the galaxy, where the oldest stars are found and the most advanced and best-resourced civilizations are likely to be located.
By focusing on radio signals, however, the search for intelligent life has been extremely limited. As in forensic science, the clues left by alien activity might be very subtle and require sophisticated scientific techniques. An advanced civilization might engage in large-scale astro-engineering, reconfiguring its planetary system or even modifying its host star, effects that could be observed from Earth or near space. The physicist Freeman Dyson once suggested that an energy-hungry alien community might create a shell of material around a star to trap most of its heat and light to run its industry—a solar energy program with a vengeance. Dyson spheres would betray their existence by radiating strongly in the infrared region of the spectrum. A few searches have been made using satellite data, but without success.
If a civilization endures for long enough, it might seek to migrate beyond its planetary system and colonize, or at least explore, the galaxy. The Milky Way is huge—about 100,000 light years across—and contains 400 billion stars, but given enough time, a determined civilization could spread far and wide. Our solar system is about 4.5 billion years old, but the galaxy is much older; there were stars and planets around long before Earth even existed. There has been plenty of time for at least one of those expansionary civilizations to reach our galactic neighborhood—a prospect that once led the physicist Enrico Fermi to famously utter "Where is everybody?"
How do we know they haven't been here already?
It would be an incredible coincidence if Earth had been visited by aliens during the brief span of human history. On purely statistical grounds any visitation is likely to have been a very long time ago. To pluck a figure out of midair, imagine that an alien expedition passed our way 100 million years ago. Would any traces remain?
Not many. However, some remnants might still persist. Buried nuclear waste could be detectable even after billions of years. Large-scale mineral exploitation such as quarrying leaves distinctive scars that, in the case of Earth, would eventually become obscured by overlying strata but would still show up in geological surveys. Space probes parked in orbit round the sun might lie dormant yet intact for an immense period of time. Scientists could look for such hallmarks of alien technology on Earth and the moon, in near space, on Mars and among the asteroids.
Another physical object with enormous longevity is DNA. Our bodies contain some genes that have remained little changed in 100 million years. An alien expedition to Earth might have used biotechnology to assist with mineral processing, agriculture or environmental projects. If they modified the genomes of some terrestrial organisms for this purpose, or created their own micro-organisms from scratch, the legacy of this tampering might endure to this day, hidden in the biological record.
Which leads to an even more radical proposal. Life on Earth stores genetic information in DNA. A lot of DNA seems to be junk, however. If aliens, or their robotic surrogates, long ago wanted to leave us a message, they need not have used radio waves. They could have uploaded the data into the junk DNA of terrestrial organisms. It would be the modern equivalent of a message in a bottle, with the message being encoded digitally in nucleic acid and the bottle being a living, replicating cell. (It is possible—scientists today have successfully implanted messages of as many as 100 words into the genome of bacteria.) A systematic search for gerrymandered genomes would be relatively cheap and simple. Incredibly, a handful of (unsuccessful) computer searches have already been made for the tell-tale signs of an alien greeting.
One of the hazards of searching for alien life is an inbuilt anthropocentric bias. There is a natural temptation to fall back on what we would do when trying to guess the motives and activities of aliens. But this is almost certainly misleading. Unless alien communities inevitably destroy themselves, they could last for tens of millions of years or more. It is impossible for us to guess what such immensely long-lived civilizations would be like or how they would affect their environment.
One thing seems clear, though. Biological intelligence is likely to be merely a brief phase in the evolution of intelligence in the universe. Even in our own young species, computers now outperform people in arithmetic and chess, and Google is smarter than any human being on the planet. Soon, most of the mental heavy lifting will be done by designed and distributed systems, and over time those systems will themselves design better systems. Given a very long period of development, information and knowledge processing, networks could merge and in principle expand to cover the entire surface of a moon or planet. If we ever do make contact with E.T., it is unlikely to be a flesh-and-blood being with a big head, but a gigantic throbbing artificial brain. Whether such an entity, inhabiting the highest reaches of the intellectual universe, would have the slightest interest in us is moot.
We have no evidence whatsoever for any life beyond Earth, let alone intelligent life. It could be that life's origin was a stupendous fluke, and that we are alone after all. But the consequences of discovering that other intelligences exist, or have existed, are so momentous it seems worth taking a penetrating look at how we could uncover evidence for it. While astronomers painstakingly monitor the hiss and crackle of the natural universe for any hint of a signal, scientists of all disciplines should reflect on how alien technology might reveal its existence in other ways, both across the vastness of space, and in our own astronomical backyard.
For many nonscientists, the fascination with the search for extraterrestrial intelligence is its tantalizing promise of wisdom in the sky. Frank Drake has said that the search for alien intelligence is really a search for ourselves, and how we fit into the great cosmic scheme. To know that we are not the only sentient beings in a mysterious and sometimes frightening universe—that an alien community had endured for eons, overcoming multiple problems—would represent a powerful symbol of hope for mankind.
Paul Davies is author of "The Eerie Silence." He is director of the Beyond Center for Fundamental Concepts in Science at Arizona State University.
Printed in The Wall Street Journal, page W1
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The search for planets in other solar systems has learned that it is common for gas giants to have orbits shorter than that of Earth.
If this is the common sort of solar system and the arrangement of our planets is uncommon then there is yet another factor working against the potential for finding earthlike life .
The Earth may be so rare that we do not find another with a million years of search.
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I would say that the major factor of discovering other civilizations is not the rarity of the Earth, but the immense distances between things. Let's say that in 2093 we get a message from a solar system 50 light years away. It will describe that civilization as it was when it was sent, in 2043, in response to what they heard from us in 1993. Then we can tell them all about us as we are in 2010 and they can get back to us in another 50 years.
If the universe is infinite, then there are multitudes of "M-Class" worlds, all or nearly all of them outside our range for travel or messages.
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If the universe is infinite,
It's not; it's boundless, but finite in size.
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It makes sense that it is boundless, but it is also really, really really large, to such an extent that so far as we are concerned if might as well be infinite.
I am not sure how you, or anyone would know, that it is not infinite.
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I am not sure how you, or anyone would know, that it is not infinite.
Big Bang says that the universe started with a singularity. It has expanded, but expansion cannot exceed the speed of light; hence, it cannot be infinite in size. Simple physics.
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If there could be more than one big bang then there could again be infinate universe.
Useing a plural on the word universe always seemed strange to me.
Untill we know what caused the big bang how can we know it was the fist one ?
Or if they are common events spaced quite widely.
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Untill we know what caused the big bang how can we know it was the fist one ?
It created the universe. If there was something here before the Big Bang, it is outside of this universe and therefore inaccessible. Not even time existed before the Big Bang - time is also part of this universe.
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I read a scifi book that talked about that our religion influence our thought so much we have to believe thiers is a beginning(ex. big bang)
that the concept that time is infinite at both direction meaning past and future has no end cannot be thinkable by us
I gave it some thought and the concept is abit difficult to wrap our heads around.
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I read a scifi book that talked about that our religion influence our thought so much we have to believe thiers is a beginning(ex. big bang)
It has no religious influence. The universe is expanding in all directions. If you reverse the time arrow, it would be collapsing in all directions. Hence, everything was at one point (a singularity) at some finite point in the past.
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I think Kimba has a point: Religion does influence us to believe that there is both a beginning and an end to creation. Otherwise, the term "creation" is meaningless.
This is unrelated, however, to the evidence of an expanding universe. universe that was just sitting there and moving in no particular direction could be a permanent and static one.
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<<The universe is expanding in all directions. If you reverse the time arrow, it would be collapsing in all directions. Hence, everything was at one point (a singularity) at some finite point in the past.>>
The explanation that I read for this, in a foreword to a book on Buddhism, is that the universe is expanding BECAUSE it was formerly contracted to a single point in the past, and that since space is curved, all paths of expansion will ultimately bring all the matter on all those paths back to a single point again, from which it will all start to expand once more. Apparently the author believed that physics had thus validated an ancient Buddhist or perhaps even pre-Buddhist (Hindu) cosmological belief that the universe endlessly expands and contracts.
<<Big Bang says that the universe started with a singularity. It has expanded, but expansion cannot exceed the speed of light; hence, it cannot be infinite in size. >>
This also validates another theory I know, Schopenhauer's Theory of Eternal Recurrence: since the amount of matter in the world is finite, but time is infinite, any particular combination of matter (e.g. Michael Tee, e.g. 9-11) that once existed will exist again and again and again in infinite time.
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The explanation that I read for this, in a foreword to a book on Buddhism, is that the universe is expanding BECAUSE it was formerly contracted to a single point in the past, and that since space is curved, all paths of expansion will ultimately bring all the matter on all those paths back to a single point again, from which it will all start to expand once more. Apparently the author believed that physics had thus validated an ancient Buddhist or perhaps even pre-Buddhist (Hindu) cosmological belief that the universe endlessly expands and contracts.
The idea that all matter will eventually return to the starting point is in dispute. You have to remember that it's not just matter that is expanding outward, but that space itself is expanding at the same rate. It's not like matter is moving around in space, space is expanding and dragging matter along with it. The only way that everything will eventually come pack to a singularity is if there is enough matter for gravity to slow, and eventually reverse, the expansion. At this point in time, there is not enough known matter to do so (there is only something like 10% of the matter needed for this to happen). Hence the search for "dark matter". From what we currently know, however, it looks like the universe is headed for a "cold" ending - continued expansion until all energy is exhausted, the stars eventually all burn out, and the universe continues to expand forever.
This also validates another theory I know, Schopenhauer's Theory of Eternal Recurrence: since the amount of matter in the world is finite, but time is infinite, any particular combination of matter (e.g. Michael Tee, e.g. 9-11) that once existed will exist again and again and again in infinite time.
Actually, this is a violation of the Second Law of Thermodynamics. If there is not enough matter to collapse the universe again, then time would be infinite (in a forward direction; we already know it is not infinite in a backwards direction). However, if we are headed for a "cold" ending (for the infinite time going forward) then we are also headed for a continual lower energy level, which precludes the infinite repeating of events. If there is enough matter to collapse the universe into a singularity again, then time is not infinite in either direction - time will end at the singularity that punctuates a "hot" ending to the universe.
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that since space is curved, all paths of expansion will ultimately bring all the matter on all those paths back to a single point again, from which it will all start to expand once more.
A three dimensional example (which can be extrapolated out to the requisite number of dimensions; at least 4):
Put two dots next to each other on an uninflated balloon. Blow into the balloon (this simulates the expansion of the universe, including it's curvature). How much air do you put into the balloon before those dots come together again?
It's pretty obvious that the dots will continue to get farther apart as long as the universe is expanding.
The Buddhist take on the universe is analogous to the "hot" ending scenario (which is also my preferred version); however it appears that the evidence shows that is not the case in reality.
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Put two dots next to each other on an uninflated balloon. Blow into the balloon (this simulates the expansion of the universe, including it's curvature). How much air do you put into the balloon before those dots come together again?
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If you put two dots on a balloon, they will grow ever further apart until the balloon pops: then they will perhaps be closer together than when you started, or a much longer distance away, if the balloon broke between those two dots.
Of course, the universe is not a balloon, but only like a balloon in some ways.
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Back to the main topic: what do you think the odds are that we will ever make contact with one or more extraterrestrial civilizations? I suppose that this depends on the time period involved.
It seems to me that, lamentably, there will be no Federation of Planets, no Klingon Empire, no Dominion, no Romulan Empire, and no Breen(little is know of the Breen), or anything like them.
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<<Back to the main topic: what do you think the odds are that we will ever make contact with one or more extraterrestrial civilizations? I suppose that this depends on the time period involved.>>
From a purely pragmatic point of view, the human race won't last long enough to make contact, using the methods presently available.
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It seems to me that, lamentably, there will be no Federation of Planets, no Klingon Empire, no Dominion, no Romulan Empire, and no Breen(little is know of the Breen), or anything like them.
ok
there`s a line that people shouldn`t cross here.
you`ve gone too far now
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Back to the main topic: what do you think the odds are that we will ever make contact with one or more extraterrestrial civilizations? I suppose that this depends on the time period involved.
I think the odds are pretty good - which is why I've donated hundreds of thousands of hours of CPU time to SETI.
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I like to believe thier already here, but as hyper-responsible tourist who are too advance to make any mistakes for us to stop them.
or we're too slow to catch on.
like men in black #1 portrayed
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I see it as a possibility, though not a probability, that eventually, we will make some sort of contact. But by eventually, I mean a very long period far into the future.
Men in Black was a cool film, but I do not take it as more than comedy. I do admire those who designed the aliens.
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Men in Black was a cool film, but I do not take it as more than comedy. I do admire those who designed the aliens.
Babylon 5 was a more realistic treatment of our likely future.
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UFO being chased down the M5 by RAF fighter jets. Too Good to Be True? 2010 (http://www.youtube.com/watch?v=n_IDFDK-NYk#ws)
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Babylon 5 was not bad at all, nor was Star Trek, both were better than Star Wars. But the main problem of portraying aliens is the need to have them portrayed by humans, unless we do them as animated critters, which seems to be a path that Sci-Fi will take after Avatar and District 9. What is it they say: "The universe is not only stranger than we imagine; it is stranger than we CAN imagine." I would say that we can expect anything at any time, but it is statistically improbable to do so.
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When was the shot of the saucer-like alien thing taken?
It could have been a Frisbee® in a faked video. Or some experimental aircraft.
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When was the shot of the saucer-like alien thing taken?
Over the weekend. The British military have reviewed the video and so far they have not claimed that it was faked, but they have not really said much else about it.
The most likely explanation I have heard is that it was an unmanned drone of some sort being tested by the military, and the jets were an observation team.
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That makes more sense.
More likely than Kang and Kodos, the Space mutants on the Simpsons. They do have a saucer-shaped craft, though.
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uhm
we`re getting kinda close
Moller m200x (http://www.youtube.com/watch?v=3MwxVAZuFOs&feature=related#)
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Have you all seen this? Someone might have picked it up before in here and I missed it, but if not, enjoy. A little close to home. Doh!
Mayor sends in troops after alien April Fool panic
A local newspaper's April Fool chronicling a late-night visit by 10ft aliens sparked panic in a town in Jordan.
The Al Ghad newspaper published a front-page article claiming a UFO landing near the desert town of Jafr.
The report said the aliens lit up the whole town, interrupted communications and sent fearful residents streaming into the streets.
Jafr's mayor, Mohammed Mleihan, was fooled by the paper's prank and sent security authorities in search of the aliens.
"Students didn't go to school, their parents were frightened and I almost evacuated the town's 13,000 residents," he said. "People were scared that aliens would attack them."
A Jordanian security official, speaking on condition of anonymity in order to discuss security issues, said an emergency plan was almost enacted in Jafr.
Mleihan said he may sue the daily for its "big lie," but added that the paper had called to apologise for the inconvenience caused by the joke.
Al Ghad's managing editor, Moussa Barhoumeh, tried to defuse the situation, saying the report has been "blown out of proportion."
"We meant to entertain, not scare people," he said.
The prank was reminiscent of the 1938 radio broadcast of War of the Worlds which provoked panic in America.
http://www.telegraph.co.uk/news/worldnews/middleeast/jordan/7557129/Mayor-sends-in-troops-after-alien-April-Fool-panic.html (http://www.telegraph.co.uk/news/worldnews/middleeast/jordan/7557129/Mayor-sends-in-troops-after-alien-April-Fool-panic.html)
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I think I saw something about this.
I doubt that aliens have been here recently, if at all. I think that the first sign of their will be some sort of electronic, rather than personal, encounter, done from a great distance.
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I doubt that aliens have been here recently, if at all. I think that the first sign of their will be some sort of electronic, rather than personal, encounter, done from a great distance.
like the movie "contact"
but how about surrogate humans to be amoung us?
they may not be human, but using remote drones might be done .
but then should we be looking a those slow aging rarely sick folks with suspicion?
ex. dick clark
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I think we will just have to wait for the aliens to arrive in order to see what form their contact will be l
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duh!!
my idea is avatar in reverse
damn I`m slow
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Men in Black was a cool film, but I do not take it as more than comedy. I do admire those who designed the aliens.
Babylon 5 was a more realistic treatment of our likely future.
and, along with Serenity, the BEST sci-fi series EVER, in my opinion.
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Babilon 5 assumes that once we cross over to several other solar systems we will find and trade with and war with new species of senitant beings.
This might be quite unlikely based solely on the assumed distance between likely hospitable planets seems to be growing.
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ah, but it is science FICTION...and entertaining. Plus, Tracy Scroggins was HOT!
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ah, but it is science FICTION...and entertaining. Plus, Tracy Scroggins was HOT!
Well said .
Fiction like this can amount to a thought experiment, when taken seriously , or entertainment when not.
It would be nice to find a mentoring highly intelligent and peaceloveing advanced spacefairing people to interact with. Maybe we could become their pets?
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I doubt that there would be many Americans that would wish to be the pets of an alien race.
What I would suspect would happen would be a desire to convert the heathen aliens to Christianity and Islam (and perhaps various sects within these), and at the same time, religious crackpots preaching a garbled version of the alien religion to Americans, most likely for financial advantage.
If the aliens were red and had horns and hooves, that might make lessen the desirability, of course.
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If the aliens were red and had horns and hooves, that might make lessen the desirability, of course.
Oh, you have read Arther C Clarke?
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I believe that I read everything Clarke wrote up to 1964. I was not consciously thinking of this when I wrote that post, though. Clarke was a great SF writer, in my opinion.
Diabolical-looking characters would be a tough sell.
I sort of liked the idea of the character "Q" on Star Trek TNG. Q was a character who belonged to a race of immortal shapeshifters with many superpowers, and seemed to have all the attributes of God, except I don't think they created the Universe. Their biggest problem was boredom. They'd all been everywhere and done everything.
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I believe that I read everything Clarke wrote up to 1964. I was not consciously thinking of this when I wrote that post, though. Clarke was a great SF writer, in my opinion.
Diabolical-looking characters would be a tough sell.
I sort of liked the idea of the character "Q" on Star Trek TNG. Q was a character who belonged to a race of immortal shapeshifters with many superpowers, and seemed to have all the attributes of God, except I don't think they created the Universe. Their biggest problem was boredom. They'd all been everywhere and done everything.
In" Childhoods End" Clarke explores the possibility that an advanced sort of alien might want to ____________(spoiler excised) the human race after we had adapted to like the notion.
One of the major caricters is shaped much as the medeviel artist might have drawn him.
The explanation being that Human beings are a lot more psycic than we realise .
If any aliens show up in the near future , then we will see them sporting a lot of new (to us tecnology) perhaps suffeciently advanced to resemble magic. Whether they have a good attitude or not will be very important.