Theory Intelligence in the Universe

As most mythologies in the past assumed that some celestial bodies like Sun or the Moon were inhabited, or the Jewish Talmud announces, without much elaboration, at least 18,000 worlds, Christianity considered aliens like a aberrant idea. It is modern era thinkers as they tended to relativize the place and role of mankind compared to traditional geocentric cosmology, who gave more importance to that view of cosmic pluralism. Since the end of the 19th century A.D. the question of Martian life and the science fiction genre spread, leading, for example, to the UFO question in the 20th century. The search for exoplanets, the renewal of Mars studies, or views that man is star-bound (as mankind likely will be forced, a way or a other, to settle into a other planet) revived the question of exolife lately

Who Might We Encounter in the Universe?

It looks like life, everywhere in the Universe, in any case, would succeed the most on the following basis that the six most frequent chemical compounds in the Universe are the hydrogen, helium, oxygen, carbone, neon et nitrogen. Water, acting as like a solvant, is triggering chemical reactions favourable to life is another element to life. A solvant is always needed may it not be water. Life always is tending to form more complex assemblage. And life has a large adaptative potential

As the evidence is mounting for primordial forms of life teaming in the Universe we do not have such hints about any alien intelligence so far. The only example of intelligence we have is our own story. What does that story tell? It tells that we gradually came to use tools and eventually got religious feelings and that we wandered along the planet. Once prehistory passed, we invented agriculture, State, and laws as since two centuries were have entered an industrial way of life. As far as our interest for the skies is concerned, we do not know much about how Homo erectus was looking at the sky. Then we began to look at the sky but for divination mostly as a rationalist approach of the sky dates back to the 16th century AD only. Our means of far reaching communications appeared about a century ago. Mammals may have some apparent kind of intelligence but show no sign of ability to communicate with any alien intelligence as marine life or reptiles are far less endowed still. Algae and bacteriae might just be able to travel embedded into space rocks or comets. Assuming that any form of alien civilization exist somewhere in the Universe and has about the same technological intelligence and interest about space which we have now in the 21st century, what might it do about space and the Universe? Here are the elements for the easiest part of the interrogation

A trickiest part certainly works on this idea that intelligence might have taken forms different from what we have seen at Earth. How that might work? First we might imagine that even whether the general conditions of an alien planet would have been similar to Earth's, selection would not have worked the same way it worked at Earth, leading to unpublished forms of life like beings having a reptilian appearance with a mammal intelligence or bacteriae with human aptitudes. Further we might imagine that bacteriae or more advanced forms of life might have a sense of intelligence and communication which would be of their own and which we would not have deciphered still. Some alien equivalents of algae or dinosaurs would have knowledge and communication ways of their own. Or that rocks might communicate with stars or trees with comets. Exobiologists further are understanding that the color of the parent-star light of a exoplanet even could influence the color of plants there, with planets sporting blue, or dark vegetation

Most of alien life likely would be of the sort of microbes or simple animals like the forms we knew at the Earth for most part of the geological history of it. Under that form, some, like astronomer Stephen Hawking, think that aliens could pose a threat to Earthlings however. At last, as far the existence of men strictly similar to us -homo sapiens sapiens, that is, on one, or several, or numerous planets in the Milky Way Galaxy or the Universe at large- is concerned, generally, the question looks like one ought to assume that on such planets the evolution of life would have occurred exactly following the same events and Darwinian branchings out. That should also means that life is progressing according a uniform way, from primitive celles to more complex beings, to dinosaur-style reptilains and then to mammals, primates, etc. In terms of how much Earth-like planets with life supported could exist, two views mainly are opposing between them. The 'principle of mediocrity,' as advocated by scientists Carl Sagan or Frank Drake, states that our Earth had nothing remarkable as it is a typical rocky planet located in a mean solar system, into a common region of a common spiral-barred galaxy. Hence, do they advocate, complex life similar to one on Earth likely is common across the Universe. The 'Rare Earth hypothesis,' at the contrary, as advocated by Peter Ward or Donald E. Brownlee, states that complex life on Earth required a rare combination of events and circumstances and that any planet claiming to complex life should have been and be very similar to Earth in terms of its geological history, for example. Hence complex life should be uncommon in the Universe. It might generally, notwhithstanding any thought about models of life based upon other elements than oxygen, or water, like it is at Earth, that the occurrences which led, on our planet, to Homo sapiens sapiens are very rare and pecular to Earth. That might be the case for gravitational realities facilitating plate tectonics, a low number of extinction events, the evolution of simple early cells (prokaryotes) into complex ones (eukaryotes) -a event which occurred once, or the slow and focused evolution on mankind since its beginnings. Other views however defend that basic life could exist from mechanisms other that those seen at Earth as complex life features, most importantly, might be fundamental everywhere in the Universe like a skeleton which withstands gravity, bilateral symmetry, sight, or photosynthesis. The question at last complicates itself from the intrusion of politics. Some views about the subject resort to some political views, some to others like, for example, the Rare Earth hypothesis is most suited to the anthropic principle according to which Universe looks fine-tuned to how it is nowadays and to the existence of mankind. A plausible view might be, maybe, that Earth be the sole place in the Universe with the real Homo sapiens as primitive, cellular forms of life likely might be found across the Universe. In any case no evidence of intelligent extraterrestrial like ever was found since the inception of modern astronomy nor did any exoplanet found matching the features of our own Earth

How Might we Encounter Them?

With the first part of the story, what are our chances to meet aliens? It is now well admitted that there is one civilization like our each 150 light years in any galaxy. Given our technology some might have gone further than us in the same direction and would certainly have gained more potent tools. Some 55 Cancri SETI program teams would surely listen in search of other places of intelligent life -and beam. In this case the farthest we may beam, as far as we are concerned, is at light speed. Recently just our TV and radio leakages from the 1920s were our sole hints from ourselves as they are now 80 light-years away bringing some mail plane era broadcasts of the 1930s to some distant Arecibo. TV transmissions however don't travel all that far and it is nearly impossible to catch old shows from more than a few light years away. The most recent trend among the extraterrestrial searchers is to send intentional radio messages outwards with a strong debate now encours about whether we should or should not given that we could not meet pacific and well-intentioned extra-civilizations but predators instead and thus hint to our position in space. The other way, we should surely get such news for a faraway world in a more or less distant period as we might catch some voluntarily or unvolontarily beamed signals. That's the SETI logics. SETI is using the Arecibo radio-telescope at Puerto Rico to listen to any potential message coming from an alien world

As far as the second part of the story is concerned, the question obviously seems to be to work further about what life is, how it might have worked and evolved differently from Earth at some other worlds. Some exotic forms of life and intelligence might be trying to communicate with us, or might inadvertently beam signals we are still unable to catch. This might be some part of the NASA logics. The Terrestrial Planet Finder (TPF) space mission will look for terrestrial planets in our neighbourhood and this will surely help to better characterize how rocky planets form, appear, and evolve. Or Mars and gas giants moons missions will help understand the primordial forms of life. Such data will surely be valuable for a more comprehensive view of what and who we might encounter in the Universe

What About Extraterrestrial Search Programs?

In recent times, questions about ETs began in the early 20th century were a center of interest with radio pioneers such as Heinrich Hertz, Nikola Tesla or Guglielmo Marconi, for example, foreseeing the use of radio waves for 'interplanetary communication.' Marconi caused a considerable public stir in 1919 as he had tried to determine whether some unusual radio signals came from Mars. Giuseppi Cocconi and Philip Morrison from Cornell University proposed in a paper in 1959 that the microwave part of the electromagnetic spectrum seemed to be the most appropriate for the search of extraterrestrial life as such waves are the most able to travel long distances as extraterrestrials likely would use the 1,420 MHz frequency for their transmissions, which is a wavelength of 21 centimeters. That wavelength further is the one at which the neutral hydrogen atom periodically emits one photon. Which means that any advanced extraterrestrial civilization wanting to contact, would try with a wavelength associated to the most abundant compound in the Universe. The 1420 MHz bandwidth is nowadays protected as terrestrial transmitters are forbidden to transmit within it. A young astronomer, Frank Drake, on the other hand, who eventually was the proponent of the famed equation pondering the diverse factors for advanced civilizations in our Galaxy, was the first to start, by April 8th, 1960, a real quest for extraterrestrial intelligence, with a 85-foot antenna at the National Observatory of Radioastronomy in Greenbank, West Virginia through 'Project Ozma'. He used the 1,420 MHz frequency and began his search with Epsilon Eridani and Tau Ceti, both stars close and similar to the Sun. The quest unluckily proved unsuccessfull as it remained however a model for the following, SETI programs. The SETI program was a partly public-partly private funded search with the Arecibo telescope, Puerto Rico, looking for artificial radio signals which might be heard. During the 1970s, NASA began some funding into SETI research in the 1970's, with some difficulties in the U.S. Congress which astronomer Carl Sagan helped to settle. That also was the time of private funding like by the Planetary Society Sagan was one of the founders, or the one of the interest for ET in the Soviet Union. NASA meanwhile had formally endorsed the SETI program by 1988 as funding again was contested by Congress. As the High Resolution Microwave Survey (HRMS) had been set up by the agency in 1992, with the use of the Parecibo antenna or JPL's Deep Space Network (DSN), funding was cancelled by legislators two years after only. SETI turned private, with the non-profit SETI Institute initiating the 'Project Phoenix.' By 1999, a renewed interest into ETs in the general public brought NASA to launch its Origins program and the question of exoplanets. Interestingly the scientific community worlwide is not interested in the search for extra-terrestrial intelligence. SETI is listening at a frequency which is located just between the hydrogen's and the hydroxil's. This has been dubbed the 'water hole' region of the spectrum as it is seen similar to the water point where wild animals are coming to drink in the savannah, just like intelligent civilizations might meet at this point to communicate. What SETI is looking for is artificial radio signals. One of the way to spot such signals among those heard is the fact that they should be heard repeatedly. Some scientists think that a signal should be heard up to 20 times to be labeled extra-terrestrial. SETI spotted about 10 unexplained signals but they mostly are lacking this repeatibility. The sole outstanding signal spotted during the four decades SETI program, is one from a SETI project at the Big Ear radio telescope of The Ohio State University, and detected on August 15th, 1977. That signal was bearing expected hints of potential non-terrestrial origin and lasted 72 seconds as it was 30 times more powerful than the ambient noice of the Universe. It unluckily never was detected again. Its inventor, Jerry R. Ehman, circled the signal on the computer printout and wrote the comment 'Wow!', hence the name, the 'Wow! signal.' The signal was emitted about the frequency 1420 Mhz or the one of hydrogen, the most common element in the Universe. The signal came from constellation Sagittarius, the Archer, roughly 2.5 degrees South of the 5th-magnitude star group Chi Sagittarii. Tau Sagittarii is the closest easily visible star. Some have even suggested it could have come from a moving, ET space vehicle. The Wow! signal generally would have required a 2.2 gigawatt transmitter, a facility which a advanced civilization only could provide for. By 2012 tweets messages were gathered by National Geographic Channel and beamed into space on August 15th in the direction from which the Wow! signal originated, in a work with the Arecibo Observatory to develop the best way to encrypt the transmission. Natural or artificial signals generally may be affected by a frequency shift when emitted by -or from- a rotating or orbiting body. Russians too embarked into the extraterrestrial search, with Nicolai Kardashev, from the Moscow Sternberg Institute, proposing a classification of civilizations into three categories. Type I -to which the Earth is belonging to- are mastering a technology level which allow those to control the energy of the planet's mother-star which is reaching the planet. Type II have reached a point when they are able to entirely control the energetic process of their star, as Type III are to those of their entire galaxy! Such a classification is leading to that type II and III civilizations are the easier to find, compared to that the US mostly searched for type I. NASA in 1992 began a two-part project known as the High Resolution Microwave Survey, the larger extraterrestrial search program ever. NASA Ames Center was to focus upon 1,000 stars similar to our Sun as the Jet Propulsion Laboratory was to search the whole sky, looking for weak and strong microwave signals respectively. The project unluckily ended less than one year after is start as the US Congress canceled funding. That project later was revived under 'Project Phoenix' by the SETI Institute, a privately funded organization, which is performing its searches in highly sophisticated areas (by June 2012, after 35 years of fruitless hunting, director of SETI Research turned to chief fundraiser to the institute in the purpose funds will allow SETI researchers to keep searching ETs). The Planetary Society at last, is at the origin of varied projects as it is experimenting with varied techniques and investigating the whole sky. Search for laser light pulses, on the other hand, began in 1998. The Allen Telescope Array, a network of radio dishes in northern California, has began collecting ET data since 2007. By 2011 however, a steep drop in state and federal funds forced the shutdown of the facility. The array had been built by the SETI Institue and UC Berkeley with the help of a donation from Microsoft Corp. co-founder Paul Allen. The institute, however, was hopeful the U.S. Air Force might find the dishes useful as part of its mission to track space debris and provide funding. The dishes could also gather more general scientific data. The search for extraterrestrial intelligence will also keep on using other telescopes such as a dish at Arecibo in Puerto Rico with only about two weeks a year slots

In the ET domain, the Fermi Paradox is the constation, enounced by famed, Nobel Price, physicist Enrico Fermi, which remarked that, should some intelligent life be extant elsewhere in the Universe, it should have since long had the occasion to develop to a high level of technology and thus to have already conquered our whole Milky Way Galaxy. Fermi, in the 1950's was quoting: 'If extraterrestrials are extant, where are they?!" As far as visits by aliens to Earth are concerned, some specialists contend that to drive to a insignificant planet like Earth, around a uninteresting star like the Sun would probably not occur more than once in 1,000 years or so, even if assumed that every intelligent alien community makes something like 10 launches a year. Against Carl Sagan's view that intelligence has a high survival value in the Universe, critics point to that, since the beginnings of Earth, 50 billion species have evolved as one only, ours,managed to develop, at some point, a advanced technology or since 10,000 years twenty or 20 distinct civilizations have emerged and only one -the Western one since the 16th century A.D.- achieved technological capability. A other argument too is that would have been the primordial 'evolutionary soup' be a few degrees hotter or colder, mankind would not have eventually emerged. The quest for extraterrestrial civilization is not a new one on the other hand as the German mathematician Carl Gauss, for example, proposed in 1822 to plant a gigantic triangle with pines so to be seen from far away from the Earth and hint to the Pythagore theorem. Or apart from those astronomers who believed they had been seeing chanels on Mars, Franz von Gruithuisen (1774-1852), a astronomer from Bayern, said in 1824 he had seen a city on the Moon, in the vicinity of the Schröter Crater